Hi guys: like it says, everything is fine with this reverb..in fact its great....but.....
i added a bright / warm-normal switch, (using middle and outer lugs of an spdt) , and i just can't get the bugger to not 'pop' when switched. (used a 47n/22n as i didn't have 68n ::))
ive tried all sorts of remedies to no avail....any solutions, i have it on breadboard so i can try any suggestions!!!.. :). cheers guys.
schematic:
(https://dl.dropbox.com/u/7464107/megaverb.jpg)
edit: R.O.tree (mike) suggested a 1M from VB to the right of the switch caps, ...much much better.!!!!... thanks mike ;)
For one less part, return the bottom of R15 to Vbias.
However a large resistor across the switch is a good general plan when a cap runs from mid-voltage to ground.
Rob,
Looks nice! I always love your schematics... easy to follow! Wouldn't mind doing a reverb...
~ Jim
Is this based on the Tenebrion?
@paul: cheers, i'll give that a go.
@jim : cheers man, yeah its a pretty cool verb...with the feedback control it stretches the time out further than the spec 2.8secs., and the damp is nice too. for more subtlety.
@jon: never heard of that, this was originally the 'box of hall schematic' , but it was way too bright compared to bypass signal imo, so i tweaked the 'tone' of it,
armndry(larry) suggested the feedback idea...which is really cool, (R13 sets the max feedback) lower values with self oscillate, but i have it just on the edge of that.
i added the bright/warm . warm being 'normal tonal unity' , and bright which just lifts it, which is really sweet with my electro acoustic , and nice n plucky on my ibanez rg470. a cool option.
i also added the volume so i can tweak volume of bright/warm, plus i'm pretty much a control freak...well worth a build. sounds great with delays/chorus etc...and nice to have it under foot rather than on an amp. ;D
original 'hijacked' thread.. :)
http://www.diystompboxes.com/smfforum/index.php?topic=93421.msg891944#msg891944
aha...mike (R.O Tree) suggested this, and it works great, totally silent switching. excellent. cheers mike. ;)
i shall try some other fets too just to try...
revised schematic.
(https://dl.dropbox.com/u/7464107/reverbfinal.jpg)
sorted. ;)
Quote from: deadastronaut on January 29, 2013, 03:13:22 AM
@jon: never heard of that, this was originally the 'box of hall schematic' , but it was way too bright compared to bypass signal imo, so i tweaked the 'tone' of it,
Ah, yeah, same thing. "Tenebrion" is CultureJam's improved version (with the feedback loop) that he did with Grindcustoms very recently, basically trying to get higher headroom. Anyway, I had a board for it on the way, and I was looking at extra things to do with it. Your bright/dark switch for the reverb seems like a cool idea.
@jon: gotcha, yeah its pretty cool. when the reverb is dialed all the way off, there is proper 'tonal' unity now.
ive just made a layout with the new schematic , a little messier than i'd like but i'm aiming to get it to fit a 1590b. :)
Quote from: deadastronaut on January 29, 2013, 09:26:17 AM
ive just made a layout with the new schematic , a little messier than i'd like but i'm aiming to get it to fit a 1590b. :)
If you're short on PCB space, Paul's observation that the cap needed to be "pulled down" is one part instead of several.
Your pop was for the same reason that input and output caps without pulldowns pop on effects. The cap gradually leaks down. If you're switching a cap carrying audio signal, you always need to pull both ends to a DC voltage that is not changed by the switch operation. Otherwise, the cap will have to charge, and will then discharge depending on the switch state, and you'll get a pop.
In your case, pulling the switched end of the cap to Vb with a large resistance, maybe a meg or more, would do the trick. So would Paul's trick of pulling the "ground" side to Vb if you also pulled the switched side to Vb.
It lets you use fewer parts. But the JFET switch works too, by making the transition very slow.
cheers R.G.
nice explanation, thanks.
ive managed to squeeze the fet circuit on there, i did try pauls suggestion but there was still a little pop, not as bad but still noticable.
ive been trying this fet switch all day and its fine. 8)
i just need to brush up on my layout skills a little more i think. its like doing 12 crosswords at the same time, but i masochistically enjoy it , strange but true... ;D
Quote from: deadastronaut on January 29, 2013, 10:27:34 AM
ive managed to squeeze the fet circuit on there, i did try pauls suggestion but there was still a little pop, not as bad but still noticable.
ive been trying this fet switch all day and its fine. 8)
Well, if it ain't broke, don't fix it! :icon_biggrin:
Great!
;)
ok heres a test vid, with normal/bright, electro-acoustic. (simon&patrick)
reverb full , damp off, just adjusting the length...(feedback)...as per schematic above ok.
Very nice, Rob. Have one of these:
(http://dl.dropbox.com/u/7464107/sausage.jpeg) ;D
So nice, I'm just gonna have to build one. BTW, which flavour of BTDR-2H did you use - L, M or S? Or does it even make a difference?
Nice one ....... I need to get me one of those reverbe BTDR-2H and try this.
Now this is funny!
Just yesterday I got an hour lecture on poping in Mark Hammer's office. I just went to get 2 switches and come back with a ton a new knoledge. (and the switches!)
Having Mark as a friend as put my effect building/knoledge on warp speed!
@marc: i used the ' L'... thanks for the rare sausage pic... i have 2 now. ;D
@alain: very cool, my friends just talk bollox mostly... :)
Sounds great Rob, nice demo.
cheers ian, highly recommend building this one...very useful.. 8)
Quote from: bluebunny on January 31, 2013, 10:43:40 AM
Very nice, Rob. Have one of these:
(http://dl.dropbox.com/u/7464107/sausage.jpeg) ;D
So nice, I'm just gonna have to build one. BTW, which flavour of BTDR-2H did you use - L, M or S? Or does it even make a difference?
I know we already voted against a karma system for this forum.......but what about a sausage system?
ok I want to make this... mind if I give my hand at a Vero of it... or can one of you do that... I'm such a hack. XD
feel free, ive made a pcb layout but i want to verify it before posting it ok...
;)
Nice sounding reverb!!! :D
no its not... ;D
Quote from: deadastronaut on February 03, 2013, 07:15:00 AM
no its not... ;D
Ok-If you insist, it sucks!!! :P I just wish I had a reverb that sucked as much as this! I must need to have my hearing checked because I really thought it unsucked. ;)
What would it sound like with a twangy electric playing "Long Cool Woman"?
i tried that already, it sucked.
;D ;D ;D
it sucks so bad i might as well build it just to match my other terrible sucky pedals....just for continuity. :icon_mrgreen:...
Hmmm... What is it you don't like and how would you like it to sound?
lol...i don't like it with a guitar plugged into it, but i'd like it to sound as if their was a guitar plugged in to it, that was pretending not to be plugged in to it at the same time, so as not to sound like anything was plugged in to it though it actually is...
:D
I think that this thread has gone the direction of the "What do you do when it does work" thread!
#10. Babble aimlessly to anyone that will listen for the sole purpose of exuding the pure joy and excitement that stems from the happiness and contentment with your new build! ;D
hi larry,
indeed ...erm....i think.. ;D
Quote from: deadastronaut on February 03, 2013, 02:23:00 PM
lol...i don't like it with a guitar plugged into it, but i'd like it to sound as if their was a guitar plugged in to it, that was pretending not to be plugged in to it at the same time, so as not to sound like anything was plugged in to it though it actually is...
:D
Have you tried listening to it sober? ;D
cheers jon, i'll dig out a beer datasheet that explains how to do it..... ;D
Sound clip was awesome. It sounds like it's removed a bit from the 'spring' reverb and more into hall. Is there a way to make it do the spring thing as well?
hi matthew,
on that demo i had reverb up full, and damp off, time full too...
heres another demo with a bit of twiddling about...(before the time/feedback was added...
just adjusting the reverb amount and damp...
In keeping with your reverse judgement where good=bad and bad=good, I'd say that was really bad! :icon_wink:
yeah its pretty @#$%ing awful... ;D ;)
update: don't build this yet....got a problem houston....beep.............beep.......
heres the problemo.
everything is fine and dandy with just guitar and reverb....levels at bypass/on and unity etc...fine...
however...
when adding a distortion in front (reverb off) bypass and distortion level unity ...everything ok....
but...as soon as i turn on the reverb...there is a massive level drop....though they are the same settings. ???.....gonna have to sort that out...glad i tried it with distortion before building it.. :icon_evil:
any ideas?
That's a shame, because I just finished making the PCB for you :( That said, I made a bit of a boo-boo with the solder mask (pulled the backing off too early) - it is solid as a rock, but it's not as pretty as usual so, if you decide to change the circuit, I'll just make another.
What distortion pedal are you using? Link to schem?
Maybe an impedance matching problem which is way beyond my ability to understand.
That 33k/4n7 combo on the front end rolls off stuff above about 1Khz, could you just be hearing a loss of top end with the dirt that you don't notice clean?
@mike: bummer eh... :(
@ian: no its way more than that, i bypassed the 33k/4.7n and yep its brighter but no where near ..as soon as i put distortion on, whoomph...level is sucked down...and very tonally different.. ???
like john said maybe an impedance thing..but way above my spaced out head too.. :)
my distortion btw:
http://www.aronnelson.com/gallery/main.php/v/chickpea/SPITFIREV3.jpg.html?g2_imageViewsIndex=1
maybe needs some kind of buffer in front?...
If you are using a TL074 in the reverb then the max input impedance is ~690k (1M || 2.2M), so this should be OK. You could increase the pulldown resistor to e.g. 10M, which will bump it up to 900k.
I might be barking up the wrong tree, but looking at the distortion schematic, the first thing I noticed was that the volume pot seems quite small considering it has quite a lot of passive tone shaping behind it. Can you try a 100k+ pot here and see if that helps.
hi sam , ive just tried my ax1500g pedalboard into it and its the same massive vol drop too...when turning on reverb....hmmmmm...
edit: i'll record a loop on my pedalboard and pump it in there, whilst adjusting the input R/C .... :icon_idea:
edit:.. ok, i swapped the 33k, 4.7n for 220r/1nf...much better with distortion.....still a little tweaking to do though...but much better level/tone unity now...not perfect, but better... :)
I should have suggested that as the easy option, but I guess you worked out you had a 10k/33k ish voltage divider problem.
You will probably get more output from your distortion with a bigger vol pot, but that is probably a discussion for a different thread. Is the reverb now good to build.?
hi sam, cheers man,
i would say almost ready....i'll have it nailed tonight/tomorrow hopefully...i think. ;)
sounds right with my pedalboard....i'll re-try it with seperates..
re the distortion pot: i only need it on 9 oclock to be unity...may have to revisit/mod that. cheers..rob.
Quote from: deadastronaut on February 07, 2013, 01:03:51 PM
re the distortion pot: i only need it on 9 oclock to be unity...may have to revisit/mod that. cheers..rob.
Fair enough - sounds like it is doing the trick.
Whereabouts did you get the Belton brick from? I have seen that das musikding have them, but am wondering if there is a UK source.
hi sam: yep i got mine from musikding too.
seems lke you may be right on that pot lark...
the pedalboard was fine...korg ax1500g
then i tried my dr boogie and that was fine too...so the spitfire seems to be the culprit. i'll swap that 10k pot out and try it...
i also took out the reverb input R/C too...report back tomorrow. ;)
update:
in the cold light of day..and further tinkering.....there is still a problem with this.
it seems near impossible to get it to be happy with clean+distorted without a massive change in vol and tone....
when i leave out the input RC its pretty much bang on with distortion (dr boogie) ...fine. = ...only a slight tonal change....
but then when distortion is off , there is a massive difference between reverb on /bypass....which then needs input R/C to be more like e.g. 33k/4.7n...
this is all tested with reverb level minimum/off .....short of having a switching input R/C for dist/clean, which would be a nightmare...i'm at a loss.
i'd like to hear from anyone thats built these reverbs , and what their findings are with other pedals in front.....comparing tone/level etc....
@#$%ing reverb :icon_evil:..
There's a lot of passive tone/vol control circuitry at the end of that Spitfire circuit, which might mean that its output impedance is higher than we're used to in these circuits. Try putting a buffered pedal in between them (any Boss pedal would do, as they're always buffered whether the effect is on or off) and see what happens. If it works, just make a little buffer to go on the end of the Spitfire.
hi mike, its the same if i use my dr boogie too though... ???
i'll whack my old boss ce2 in between and see what happens...cheers. :)
Hope this doesn't sound like I'm taking the piss, but are you sure what you have on the breadboard matches your schematic?
With the reverb turned all the way down and output on full, the output should be at least as loud as bypass, there's nothing in the dry path that can cause a volume drop.
@ian: stop taking the piss ;D schemo/bread the same man... ;)
@mike: voila', i put the dr boogie> boss ce2> reverb ....(no r/c on input...
much better now on distortion and clean....yay!!!!...
tried spitfire > boss ce2> reverb....voila' again...(no r/c on input..
so its definately a buffer issue.
sooooo......can i just add a buffer to the reverb, rather than butchering the dr boogie+spitfire...make sense? :icon_idea:
the reverb will be at the end of my chain anyway...
If you ditch the 33k/4n7 does the volume loss problem go away? Without them the first stage is a buffer so if you still get weirdness, I'd start thinking it might be a bad opamp, or a dodgy or wrong value cap or resistor.
I'm with Slacker - you have a perfectly good input buffer with a low-pass filter in front of it. What happened when you tried the 220R/1nF RC filter?
Are you using a TL074 like the schematic says? If so, I always get the pinout confused on those bad boys. Any chance I am not alone (and/or the IC is toast)?.
ok..heres a clip of whats going on. i ve checked over the breadboard, swapped 074 for new one...same thing.
spitfire>reverb.
1st clip clean,.... 2nd clip reverb on,..... 3rd clip dist on, reverb off, .......4th clip dist on, reverb on....
no r/c on input....just a 33k on the out to keep level unity-ish for now...
note the tone difference on clean bypass compared to reverb on......then massive vol loss when reverb with distortion... ???
https://dl.dropbox.com/u/7464107/bastard%20reverb.mp3
edit: heres a clip with a boss ce2 too..
spitfire>boss>reverb
1st clip clean,.... 2nd clip reverb on,..... 3rd clip dist on, reverb off, .......4th clip dist on, reverb on....
https://dl.dropbox.com/u/7464107/bastardreverb2buffer.mp3
so something is amiss...as it behaves nicely with the boss(buffer)..hmmm...
now here is a clip of the spitfire>reverb with no 33k on end for unity...just straight out from the 1uf.
1st clip clean,.... 2nd clip reverb on,..... 3rd clip dist on, reverb off, .......4th clip dist on, reverb on....
https://dl.dropbox.com/u/7464107/bastrev3.mp3
see my dilemma? :(
What are you plugging into for those clips? The difference in tone on the cleans in the first clip could be whatever you're plugging into tonesucking your guitar and the reverb then buffers it adding brightness. Also worth noting the bright switch will affect the dry sound as well as the wet so that would add treble if it's switched on.
That doesn't explain the volume drop with dirt though.
If you stick the boss after the reverb does that cure the problem?
I got more confused and started looking at your verb schematic for any other/obvious problems. I had 2 thoughts; take them with a pinch of salt.
1. I am lost as to whether the RC filter is causing your volume drop/tone problems or not, but why not move it after the input buffer. You already have 10k resistors to the wet and dry sides of the circuit. You could then use 15n caps to Vb to get you a similar roll-off. I would use a smaller cap for the dry signal though so it is a bit more unadulterated (1kHz seems a bit low).
2. Ditch R11. As it stands you have a 33k bias resistor to a low impedance ground (Vb) and another 10k/33k voltage divider problem, which means you will not get unity volume out of your dry signal. I don't see any reason for the bias resistor as IC1b and IC2d are DC-coupled (no cap between them). If you find you need the bias resistor, increase it to >>10k (i.e. 1M).
@ian: i'm just using my usual setup that i use everyday.. guitar, ibanez rg470>spitfire>breadboard with reverb on it(true bypass breadboard btw) > mixer>amp.
bright switch is off...
just tried the boss pedal AFTER the dist/reverb...perfect!!! unity level, unity tone too..much much better......(btw , thats with no volume control on reverb at all, just straight out of the 1uf..)
so i need a buffer on the end of the verb yeah!!!!..can you recommend a suitable buffer?.
@sam: i'll try a buffer , and if that don't quite work out i'll give that a go man..
cheers guys...getting there. :)
Sounds like you are making progress. Without the volume pot (which is probably not necessary for a unity gain pedal), you already have a pretty good output buffer in terms of low output impedance. Did you always have the vol pot missing?
hi sam, no, but i had the volume set to unity, and there was still enough left for a boost too..
which i quite liked for volume swell type stuff etc...and was handy to just make up the level when the reverb was on max..
i pulled it out for the above final clips though...
i'll have a poke around and see if i can find a 'close' to boss buffer and try it out...
edit:
i tried the first fet buffer on the reverb out here, which was perfect with distortion/reverb on/off , but still had the massive difference in levels issue on clean...hmmm...
http://www.muzique.com/lab/buffers.htm
Put the FET buffer in front, Rob
As an experiment Rob, try guitar straight into mixer compared with guitar through just the buffer into mixer. See if you get any significant volume and tonal changes, if you do it suggests the mixer is at least part of the problem. If not I'm officially stumped.
hi mike , i tried the fet buffer in front of the reverb, distortion was fine with reverb on/off...but clean with reverb on/off the same issue.. ???
@ian: i'll try that now...
ok just tried the buffer on its own into mixer...and yes the vol increases a good amount with the buffer on compared to bypass... :)
out of curiosity i tried the buffer into my roland micro cube on a clean , and it was fine...hmmmm...yay!!!..
then i run the distortion and reverb into the roland cube and that was fine too....on/off clean dist...fine yay!!!...
soooo...the problem was my ''out'' all along, as in my mixer...wtf?. ???. ive never had this problem before!!!!...how would i go about curing that?...
Didn't realise the reverb section had gain. Cool.
You could appropriate the op-amp used to buffer Vb (nice touch, but probably not essential) and stick it after the volume knob as a non-inverting buffer.
Oh, and I still think you should pull or increase R11 as it should be dropping your dry signal quite a bit.
hi sam; tried the R11 mod..sticking a 1M lifts the level a bit....33k is about unity.
as for your opamp suggestion...got a diagram of what you mean?...i'm a dumbass. ;D
He means take your Vb off of R1/R2/C3 junction and use the opamp IC1a as a buffer after the volume pot. The buffer would be this guy here:
(http://www.muzique.com/images/buff7.gif)
Yes - mth5044 beat me to it. However, that adds to the parts count and is a bit messy. I just realised that IC2d is a differential amplifier - interesting idea - and so much of what I was saying about unity gain is not quite right. The 33k R11 is probably going to work just fine in this case (although 1M will too).
If you want to stick with the op-amp output buffer, you might be better off using an inverting op-amp with a pot in the feedback loop to give you your level control. You could remove the 1uF cap and level pot, add e.g. a 10k resistor to the (-) input of an op-amp and put a 10k or bigger pot in the feedback loop. The 1u cap then goes on the output and you have a low-impedance buffer/volume control. I think this will work, but I am starting to realise that there are a few things going on in this circuit that I had not considered, and there are probably a few more I haven't yet.
Glad you got it figured out Rob even if the answer wasn't what you wanted. If it's the same mixer you mentioned in your D.I box thread then according to the manual the line inputs, I guess you're using those, have an input impedance of 10k Ohms. This will seriously reduce the volume from your guitar and roll off treble, this explains why you get the volume boost and extra brightness switching the reverb on. It probably also explains the volume drop with the dirt pedals, the input impedance will interact with the pedal's volume pots and depending on the size of the pots and where they're set it will mess with the volume.
You might not have noticed it before because with dirt or boost pedals or anything that significantly alters the tone, the issue would be masked, by whatever the pedal is doing and you can just crank the pedal's volume up to overcome any loss. Pedals with always on buffers like the Boss or the Echo Base would also hide the problem.
cheers ian, great explanation, so yeah it was mixer all along....mystery solved...cheers guys!. 8)
i'm interested to see how it behaves with the DI now....
so for the record on here,
the reverb is good to go, without the 33k/4.7n.....and the volume really... :)...though when the bright switch is on (which is still cool, ) there is a bit of a jump in vol.....
but i'll have a tweak around that switch (through my amp ;D)..not mixer. ;)
I told you it was good!!! ;)
BTW-Time to change the message icon to smiley face. :)
ok...
;D
Rob, if you let me have the revised schem I can see whether I have to fab a new board or just insert jumpers/nothing depending on what's changed.
Hi mike, and everyone...
heres the schemo, i removed the 33k/4.7n...adjusted the switch resistor to ground to 8.2k, 2.2k was a little fierce imo..and had a big leap in vol too...
i removed the vol pot as its pretty redundant now...unless there is a way of making this louder?. which would be nice, but its fine as unity without the vol pot anyway..i'm just a fussy sod.. ;D
i also stuck a 1M pulldown on the out, as it popped when on/bypassed otherwise.
so here it is.. :)
(https://dl.dropbox.com/u/7464107/REVERBBBo.jpg)
Since you removed the volume pot....why don't you put a proper tone control pot in it's place. I was going to make that suggestion a while back but....you seemed to be enamored with the idea of a volume control on a reverb unit.
hi larry, i'm just going to leave it as a 3 knob version now, that'll do me fine.
cheers for all your help guys... 8)
now lets build this bugger!!! :)
Cool - it's on the list.
Nice job Rob.
^ yeah its well worth a build for sure...this will be on my setup for a long time i reckon. 8)
Quote from: deadastronaut on February 14, 2013, 05:53:00 AM
hi larry, i'm just going to leave it as a 3 knob version now, that'll do me fine.
cheers for all your help guys... 8)
now lets build this bugger!!! :)
Will there be a @#$%ing bass knob? ;D
hi jon, nope, but there may be a kazoo mode switch..... for
bwrrrrrr....bwrrrrr..........bzzzz....brrrwrwwwrw....zzzzz....type sounds...
always handy... :)
;D
Hi,
Any progress on the build? :)
@quad: not yet, awaiting pcb. ;)
Quote from: deadastronaut on February 21, 2013, 06:55:46 AM
@quad: not yet, awaiting pcb. ;)
...which I will work on tonight ;)
What size enclosure do you think this will fit in? I think I'm gonna order a brick and try it.
Just drilling to go, Rob, and trim the board to size. I might take a sickie tomorrow (feeling like poo) so I might be able to get it in the post in the afternoon. If not, Saturday morning.
@mike: excellente' news.....i'll finish up my 1590b etch design then.. :icon_cool:
stop skiving... ;D
OK, I skived... feeling pretty man-flu-ey, really. Ever noticed that significant others don't feel much sympathy for us when we're feeling icky? "I've got to go into town... you coming, or are you just going to waste the day?" etc, etc.
Anyway, the board's drilled and milled, so I'll pop it in the post Sat am.
Is there anything you need from my stash? 0.2" x 0.3" 1µF box cap with 0.2" lead-spacing, for example?
PCB is now subject to the tender mercies of HM Royal Mail, 1st Class (not that that actually means it'll get there any quicker...)
I breadboarded this and thought it's design is a bit over my head. I think it sounds really great. Thanks for offering it up to the masses. If you get a PCB Layout, please let me know. I would love to etch it single side even if it's as big as a toaster :icon_biggrin:
Will the whole thing fit into a 1590B? :)
@mike: nice one man, will probably get it monday morning then...brilliant!. 8)
@gold/quad..
1590b hopefully.. :)
The PCB is 2.0" x 1.7" (5.08cm x 4.32cm) but the brick hangs off the side, adding another 1" or so, making it about 2.0" x 2.7" (5.08cm x 6.86cm).
Rob and I have tried to design it to fit into a 1590B (he doesn't do batteries - only 9VDC adaptors on his board).
If Rob's happy, I'm happy to put my PCB art out there - be aware that I used isolation routing, so we're talking traces of 15thou and 12thou clearance from the traces and pads to the GND plane.
i'm very happy indeed!..... :)
nice one mike!. :icon_cool:
@goldstache: i have also done a diylc layout. i'll check it over and if its ok i'll post up the pdf's ok.
might be smaller than a toaster though... ;D
ok, here ya go,here's my version, i checked over the pdf's, (not as tidy as i would've liked ::)) , but i check the schematic against the layout and seems to checkout ok.
https://dl.dropbox.com/u/7464107/CME%20REVERB.pdf
https://dl.dropbox.com/u/7464107/CME%20PCB.pdf
unverified, but looks ok to my eyes... ;)
Here are the files for anyone who wishes to have a go at this little monkey...
Schematic (https://www.amazon.co.uk/clouddrive/share?s=gx_zbSdzQ5grJtkJr4ZJR8)
Layout (https://www.amazon.co.uk/clouddrive/share?s=-qnR62FQQYMqn7nwtiuf0k)
PCB artwork including solder mask and fiduciary marks to aid alignment (https://www.amazon.co.uk/clouddrive/share?s=9vSJizLKQnEjlTiEbMz1-s)
Wooo Hooooo! Thanks Everyone! Can't wait to not have to hall out my reverb tank!
Really Thankful.
Your skills astound me!
ok, got the pcb from mike this morning, (very nice pro looking board it is too) populated it..
(https://dl.dropbox.com/u/7464107/reverbbuilt.jpg)
all works fine...
just a couple of notes;
brick was backwards, and feedback/damp pots, (i'm used to 3 2 1 from the back of a pot) ...but hey thats no issue at all really (just a heads up)..
works great, and bright switch works fine too....brilliant.
i just need to trim up the ribbon wire and brick pins then fit the brick to the board..done..
cheers mike!!!!... ;)...i'll etch up my box later and get this puppy boxed 8) 8) 8)
i made a 9 led vu meter...very tempted to fit this in now too....see how it goes.. ;)
Thanks a lot for the schematic and the PCB R O Tiree & deadastronaut. Looking great! Can't wait to see the final result. :) I'm about to order a brick. Haven't yet made up my mind on which timing to get. Short, medium or long... ???
Oh... poo :( schoolboy error, sorry. I'm re-designing the board, then.
OK, here are the new v1.3 files (I just knew I should have waited for a bug report from Rob...). If you downloaded the previous ones, you might as well delete them - they're wrong!
Schematic (https://www.amazon.co.uk/clouddrive/share?s=J1G4yFYlRQMj-Jiw2VTmvU)
Layout (https://www.amazon.co.uk/clouddrive/share?s=g_oqIlPxSDMtYrO5CMU-5I)
PCB Art (including solder mask and fiduciary marks to aid alignment) (https://www.amazon.co.uk/clouddrive/share?s=i1LwzAyUReklPVpnmRAYfk)
no worries mike, its all working fine anyway..that was a dream to solder that pcb...quality job you did there man.. ;)
anything you need doing just ask ok! ;)
wow that was quick adjustment of the pcb too. :icon_cool:
@quad: this layout is for the BTDR-2H....not sure if it would behave the same with the med/small....but hey it might.
...depends on your taste/style i guess.....or build 2 :)
The solder mask is a bit of a faff to do, and time-consuming, I guess, not least because you actually have to cook it for an hour to do the final cure of the resin, but you definitely save time and effort on the soldering phase, fer sure. Sorry once again about the screw-ups.
stop kicking yourself, its fine.... ;)
sounds like a bit of a lengthy process doing the pcb then...but great results.. :icon_cool:
may have this built by tomorrow!!.finished the box .whoohooo... :icon_cool:
''ohhhhhhhhhhhh my god, its a FLYING SAUCER'' :icon_eek:...........(theremin sounds)>.....whooohoooooeeeeeeooooooohhhoooooowweeeeeehooooo......
(https://dl.dropbox.com/u/7464107/P280213_14.06%5B01%5D.jpg)
(https://dl.dropbox.com/u/7464107/P280213_14.05%5B01%5D.jpg)
(https://dl.dropbox.com/u/7464107/P280213_14.03.jpg)
reverb.
Middle led is white (always on)
Outer leds blue on/off
text could have done with being larger to get a better etch....but hey this is mine anyway....love it. :icon_cool:
Nice one, Rob. This is also on my list of must-do builds. Any gut shots? Love to see how you squeeze a board and a brick in that enclosure.
Lovin' it, Rob - particularly the retro-UFOs.
Purdy
cheers guys, yeah its the old 'George Adamski ufo...i have the book ''the flying saucers have landed'' so it seemed apt really, plus it goes well with my ufo delay too.. 8)
gut shot in a bit... ;)
yes 2 pots are backwards. ::)..i'll sort that.. ;D ;)
(https://dl.dropbox.com/u/7464107/gutshotreverb.jpg)
i slid a piece of clear plastic between the pots/pcb, this is just before i finished it off and straightened it up...
the backplate with foam holds everything firmly in place, i had to snip the bricks pins back, but now with the revised version it should be a doddle to build...
;)
special thanks the R.O.Tree (mike) for his great work on the pcb/layout, brilliant man. :icon_cool:
Didn't get past 0:33. Brilliant video. ;D
Quote from: deadastronaut on February 28, 2013, 01:33:50 PM
yes 2 pots are backwards. ::)..i'll sort that.. ;D ;)
It's allowed. For a lefty. ;)
Edit: BTW, is that a bit of reflect-o-porn going on in the bottom of the pedal?? :o
reflecto porn?
Quote from: deadastronaut on March 02, 2013, 04:42:57 AM
reflecto porn?
(http://i1160.photobucket.com/albums/q485/jdansti/93CA6F06-8A6A-4E49-AD2B-3BBB2267B3E4-4568-00000619E5134C6D.jpg)
lol, stunning resemblance... ;D
It sounds and looks great, deadastronaut.
Time to get the brick.
(http://img209.imageshack.us/img209/4711/reverb3.jpg)
looking good quad... :icon_cool:
haven't you got a small to92 voltage reg?...might be a problem getting it in a 1590b..
Good point. I might have to swap it with a small one.
I think the pinout of the larger voltage regs like you have in there are backwards to the smaller to92 versions. Not sure if you had already checked it or not, just a heads up.
Thanks, I'll keep an eye on those pins.
What is the function of this diode?
(http://img59.imageshack.us/img59/786/62040170.jpg)
It protects the regulator against input short circuit.
+1
More specifically, the purpose of protection diodes on a regulator circuit are to prevent damage to the regulator should one of the regulator's associated caps discharge back through the regulator during an input or output short.
(http://i1160.photobucket.com/albums/q485/jdansti/56122913-3E99-47C5-9797-F19D2A722C43-9545-00000B236CD5A9F1.jpg)
http://www.onsemi.com/pub_link/Collateral/LM350-D.PDF
There was a thread about this diode a while ago... It's there to protect the 7805 at power-down, or if the main circuit's V+ gets somehow shorted to GND. If the voltage at pin 3 ends up appreciably higher than that at pin 1 then the 7805 can be fried. With the diode in place, the charge in C4 can be dumped to the input side very fast and the 7805 is safe.
The thread I'm thinking of was about a PT2399 circuit and the OP had observed that he kept having to replace this regulator and the advice from the "old and bold" was that this diode was seen far more often years ago, but seems to have been forgotten about, even though you'll still see it in app notes and datasheets... but who reads them anyway? Just copy a circuit fragment, sure it'll work...
Oops, jdansiti beat me to it
Thank you all for the information. :)
(http://img202.imageshack.us/img202/9739/rvb2.jpg)
-
-
Almost ready to hook it all up. Waiting for the Belton module to arrive. I also swapped the heatsink'ed 5v regulator with a smaller one to save space.
Would it be okay to hook +9v in the current situation? I'd like to measure how the power supply section is operating before I hoop up the Belton module.
patience, patience....wait till you've got your brick . ;)
looking good, cool use of IDE leads...good idea.
better v.reg too..
:icon_cool:
^^
I use the IDE leads on some of my builds too, but I've had problems with the wires breaking at the PCB. I've resorted to using hot glue for strain relief. Have you had any problems?
@quad - Have you tested after soldering that you have no solder bridges? It's notoriously difficult to avoid them with isolation routing unless you did a solder mask as well. I'd take the opamp out, put one probe on the GND plane and touch each trace in turn to check. The regulator should be protected by the diode across it.
Quote from: Jdansti on March 10, 2013, 04:54:57 PM
^^
I use the IDE leads on some of my builds too, but I've had problems with the wires breaking at the PCB. I've resorted to using hot glue for strain relief. Have you had any problems?
This is my first time using IDE cables. They do look sturdy enough to do the job. I'll try not to bend and mess around with them too much, but gluing in such a situation would be a pretty good solution though.
Quote from: R O Tiree on March 10, 2013, 04:54:57 PM
@quad - Have you tested after soldering that you have no solder bridges? It's notoriously difficult to avoid them with isolation routing unless you did a solder mask as well. I'd take the opamp out, put one probe on the GND plane and touch each trace in turn to check. The regulator should be protected by the diode across it.
Sure did. I traced every line carefully to make sure there aren't any bridges and that the connections are solid.
Excellent - fingers crossed then :)
@quad..
stop waiting for the postman... :icon_mrgreen: ;D :D ;)
Well, the post man has finally arrived. I used my frankenstein testing unit and it does sound great! :) I might upload some demo's when it's cased up and finished. The 6 pin terminal socket is probably going to be taken out due to size. There's no need to have that. The BTDR module does fit perfectly on the board anyway.
(http://img560.imageshack.us/img560/29/frankenreverb.jpg)
Quote from: quad on March 15, 2013, 04:51:49 PM
I might upload some demo's when it's cased up and finished.
please do...
its alive....its alive....,.. 8)
Thinking of knocking up one of these just wanted to confirm with you Rob, it was designed for the 'long' delay of the belton?
Also, i will probably end up doing a demo of the pedal etc. is R O Tiree selling fabricated boards?
Cheers,
Paul
I can do - I'm making 3 for markeebee at the moment.
Quote from: chromesphere on April 03, 2013, 07:19:35 PM
Thinking of knocking up one of these just wanted to confirm with you Rob, it was designed for the 'long' delay of the belton?
Yep. I asked the same question. :)
yep the long btdr-2h... ;)
I built this tonight from deadastronaut's PCB transfer and it sounds exactly how I wanted/hoped for it to sound. I found by messing with R13 I was able to go from the default feedback with the 33k to some really cool sounding oscillation at 22k. With this tweaked I was able to get infinite-like reverb. I DPDT a 33k 22k 18K to switch it around. I might even look at adding a expression pedal output for R13.. Might be fun.
I noticed that I am getting quite a bit of a volume boost when turning on the reverb and was wondering if there was a way to add a "gain" pot to this or to bring it to a utility gain? I saw something a few pages back about a R11 mod for a volume boost but was able to figure out any more info on it. I compared the 2 posted schematics but could not figure out how R11 would help. Thanks again deadastronaut for your PCB transfer.
hi self :
cool glad you built it, and verified the layout too. 8)
yep, that 33k to 22k is worth messing with if your an oscillation junkie...i'll do that to mine eventually..
to bring it to unity you could stick a trimmer on the out so you can set n forget it, rather than another hole/pot...ive done this to a few pedals that were louder than unity too.
that'll sort it. :)
Quote from: deadastronaut on May 22, 2013, 06:31:05 AM
hi self :
cool glad you built it, and verified the layout too. 8)
yep, that 33k to 22k is worth messing with if your an oscillation junkie...i'll do that to mine eventually..
to bring it to unity you could stick a trimmer on the out so you can set n forget it, rather than another hole/pot...ive done this to a few pedals that were louder than unity too.
that'll sort it. :)
Thanks I will try that tomorrow .. since its 3:38am here and I need to get up at 7:30am for work.. haha I just really wanted to hear this thing in action.
burning the midnight oil eh....we all do that. ;D
goodnight then.. ;)
Finished this one on the weekend. What can i say...Really nice reverb...When you start to crank up the reverb there is a whole spectrum of overtones going on in the reverb effect, it almost sounds like a shimmer. I also added that oscillation mod for a bit of versatility.
Im going to record the demo / build report tonight and upload over the next few weeks. Just wanted to share my total satasifcation with this effect. I'm difficult to please these days, this one was a total success!
Paul
I must have missed the discussion about the volume boost. Paul, Rob, selfdestroyer, quad, what would you like to see on the board to cater for this? Space for a trimmer, hard-wired voltage divider or pot? Thinking about it, I could provide pads that could be used for any of those methods.
So, which would be best? Make R8 or R9 adjustable? Vol pot? Your judgements, please?
The title of this thread needs to be changed to 'best god dam DIY reverb ever :D'
Well...it SOUNDS like there is a volume increase...If your using it live I think a volume pot would be useful. Two reasons I went for a volume pot 1) didn't have a trimpot on hand 2) The loudness of the effect varies. Some settings are louder then others. That's just my opinion. What do you guys think?
Also Mike, its probably nit picking, I thought I would just mention it incase you were editing the layout. Pretty sure it was c5. It was a tight squeeze, I had to force it in a bit. And I didn't use a socket for u2 either! Yeah just though I would mention it. If there's space maybe knock it southward a few mm.
Apart from that incredibly small detail the PCB was great Mike! I've just finished recording the build report and I've mentioned it in that video as well. Thanks again!
Ill add the videos to this thread when they are all done and uploaded.
Paul
Edit: Also, does anyone care to explain what sw1 does? Mine might have a solder bridge or something, but its not doing anything interesting at all
Ahh - I used the template for little 0.3" x 0.1" box caps. I take it you used a "greenie" or something? I'll make that template larger for v1.4
As to the switch not doing anything... not entirely sure what's going on there. I checked continuity and also no continuity before solder masking. At least, I though I had done it exhaustively? The switch should connect to either +9V or 0V to move the Gate of the J201 up and down so it switches in that little filter circuit below it. Could you check that the switch is serviceable, please? OK, I've just re-checked the pinout on the J201 and it's correct. If there was a solder bridge then the switch would end up connecting +9V direct to GND, with obvious results for your battery/PSU. Next, check the voltage at the junction of R16 and the reverse-biased diode as you switch. Again, that should switch from 0V to about +9V. Next check the voltage at the Gate as you switch. Double check orientation of both the J201 and the diode - the line on the diode case should be pointing at R16, not the JFET Gate.
If all those checks are OK, then check the filter circuitry, R15, C10 and C11 for continuity. If that's OK, move onto check that the Drain and Source voltages are both at Vref (although, even with the FET switching system, it would pop like a bastid if those voltages were way off).
What it's supposed to do is switch from Bright to Warm. Rob (deadastronaut) found a mod to do this and ended up wanting to be able to switch it in and out... Hence why he started this thread and I came up with the idea (having exhausted simple resistor fixes) of using a "slow" FET switch, as often seen in Ibanez and Boss switching systems.
(https://dl.dropbox.com/u/7464107/gutshotreverb.jpg)
[/quote]
Why doesn't that Belton brick look like the ones I'm used to see?
It looks exactly like the BTDR-3 that Cusack announces in his new reverb...
Mike, the cap was a box type as well. I don't know why, but for me it was a really tight squeeze! I was just thinking if someone built it with a socket they would have no chance of fitting it in. Maybe it was just how I installed the opamp...anyway, probably doesn't matter.
Now I remember. Its a bright switch, yeah it was working at some stage. Looks like I stuffed something up, ill check it over tonight. Thanks for the detailed directions. I start with following those.
Cheers,
Paul
Quote from: R O Tiree on May 27, 2013, 06:19:15 AM
I must have missed the discussion about the volume boost. Paul, Rob, selfdestroyer, quad, what would you like to see on the board to cater for this? Space for a trimmer, hard-wired voltage divider or pot? Thinking about it, I could provide pads that could be used for any of those methods.
So, which would be best? Make R8 or R9 adjustable? Vol pot? Your judgements, please?
I finally got mine done with a volume knob and its just perfect. I am looking of making one with a short brick also and the oscillation can go from subtle to insane with a slip of a switch which is exactly what I wanted. The one think I can suggest is maybe make your ground mask not so tight to traces. I actually took your layout into Photoshop and trimmed the ground mask down a bit to help with my toner transfer.. not your problem.. more of my problem. You feel comfortable sharing the Eagle files so we can add some mods and what not? If not I understand. I am working on a small boost/fuzz to add to this to get it closer to the new Death By Audio Sunshine reverb. This is the closes I have found to the sound. Thanks again.
You nailed it in the first line Mike :D The pad that the +9v goes to the gate of the j201 was actually cracked and disconnected. Not your fault, I think I was a bit rough with the soldering on that one....anyway, easy fix. All good now thanks for the help!
Paul
@micromegas: i cut the pins shorter. ( its a btdr-2h.)
@paul: glad you got it going,...the tone switch i wanted that for my electro-acoustic, and just to add a little brightness for recording etc..
thanks to mike and his silent switching solution. 8)
volume: i just plugged mine in to test, yep, there is a volume increase, i just put a trim on the output of mine, set n forget...just for one less pot.. :)
but for neatness , and full control on another build of this , i'd use another pot for overall volume.....
My bad, Paul - I just realised that the template for a TL074 is wrong... 14-pin DIL packages should, logically, be 0.7" long. The TL074 (according the the TI datasheet) has a max length of 0.775" for the PDIP format, the same length as for their 16-pin packages. Weird. I can see why they kept the 14-pin the same size body as the 16-pin version (reduced number of dies in their machines) but it's still weird that they decided to do that. I'll change the template and re-work the PCB. Thanks for the heads-up and it's no wonder it was a squeeze. Glad you found the snag on the switching system.
@ selfdestroyer - I use ExpressPCB, not Eagle. This defaults to 12mil clearance from the GND plane. That seems to be the happy medium between pad sizes you can work with and allowing the GND plane to actually make contact and get between pads spaced at 0.1" into the next area. I know that Eagle uses oval pads for some components which would alleviate that problem to some extent (not an option with ExpressPCB). Bottom line is that I just don't like Eagle - it's counter-intuitive, inflexible and definitely too expensive for the full version (which some of my bigger projects would need). I suppose that, fundamentally, it's using toner transfer instead of UV photo-resist - it's very difficult to do isolation routing using toner transfer. If you like I could make up a board for you with the mods you want, complete with solder mask? GBP4.00 (via PayPal) including postage world-wide.
@Rob - Noted the Vol pot vote. Is there any reason why the original circuit went for a 1M output resistor? I can't see any reason that it has to be that big, given the relatively large 1µF output cap... I think a 100k pot should be more than enough? Even 47k would be ample?
That would explain it Mike! Good to hear you worked it out!
I used a 100ka in mine and it still goes above unity on max, so yeah, im not sure why it would need 1M either?
Paul
morning, :) the 1M pulldown resistor?...
i put that there to stop 3pdt pop..without it, it popped...dead silent now.
Im confused are we talking about the output volume pot value or the PDR on the output? ???
me too?...heres the final schemo as i recall ???
(https://dl.dropboxusercontent.com/u/7464107/REVERBBBo.jpg)
Quote from: R O Tiree on May 28, 2013, 04:52:28 AM
@ selfdestroyer - I use ExpressPCB, not Eagle. This defaults to 12mil clearance from the GND plane. That seems to be the happy medium between pad sizes you can work with and allowing the GND plane to actually make contact and get between pads spaced at 0.1" into the next area. I know that Eagle uses oval pads for some components which would alleviate that problem to some extent (not an option with ExpressPCB). Bottom line is that I just don't like Eagle - it's counter-intuitive, inflexible and definitely too expensive for the full version (which some of my bigger projects would need). I suppose that, fundamentally, it's using toner transfer instead of UV photo-resist - it's very difficult to do isolation routing using toner transfer. If you like I could make up a board for you with the mods you want, complete with solder mask? GBP4.00 (via PayPal) including postage world-wide.
Thanks for the reply but as of right now I think I will stick with the one I etched last week. I really like the sound of this pedal and I just need to box it up. The volume boost is not a buzz kill for me since I usually leave it on most of the time and if needed I can control the overall volume with my VP Jr but the volume trim would be a nice idea.
OK, I've slightly re-jigged the layout to cater for Texas Instruments' decision to put 14-pin devices in 16-pin package sizes...
Here are the new files:
Schematic (https://www.amazon.co.uk/clouddrive/share?s=FDyoQdy1RdEhG25GTGd1qA) (same as v1.3)
Layout (https://www.amazon.co.uk/clouddrive/share?s=G8Fknu13SoskpgjB6qWoCM)
PCB artwork (https://www.amazon.co.uk/clouddrive/share?s=lp2uhC8mTzEoKz51LxeWPk)
I've "un-shared" the v1.3 files. If anyone wants them, I can email them.
I thinking about the output resistor - R10 - I don't think it needs to be so big as 1M. If people are going to replace it with a pot, I'd think that 47k would be big enuff, given the large output cap - C9 at 1 µF.
Oh, i learnt something today! of course we are replacing the output PDR with the vol pot :P ha. I just tacted it on the end. Still sounds the same, that 1m res additional to the 100ka pot mustn't matter too much, but yeah i'll remember that next time. Actually I might clip it off. There would be a small amount of signal leaving the output to ground via that 1m res if i had to guess...
I swear this thing can do faux-shimmer. It's surpassed all of my (high) expectations! Thanks Rob / Mike for putting it together. This thread deserves more attention imo.
I recorded the sound demo last night. I upload 2 videos a week, so theres a bit of a backlog, (15 videos in the queue!) but im going to push these ones froward, otherwise it will take 2 months to upload them :) Will leave links to the demo's in this thread when they are up.
Paul
Well, the 1M resistor ends up in parallel with your 100k pot giving a total "PDR" of a shade under 91k. You could lose the 1M completely and just go with the pot, taking the wiper lead to the stomp switch.
Looking forward to the videos :)
Ahh Parrellel! Not series...learnt something else today. Yep, might as well clip it off i think! Thanks for the explanation Mike :D
Paul
It's been a while... but finally I took the time to finish it. I'll get my mic out and record some sounds out of this thing. Oh, right, there's a slight increase in volume indeed. A trim pot on the output will take care of that. :)
(http://img17.imageshack.us/img17/7125/63849907.jpg)
Very handsome pedal, there, quad. Beautifully done.
Thank you. :) A couple of things left to take care of. First off, I've decided to replace these jacks with something of better quality. I had trouble with one of these casual jacks the other day. It wasn't making contact very well and you can't have that, especially in a live situation. (i'd need quite a lot of these to upgrade the rest of my pedals)
(http://static.traderscity.com/board/userpix99/31598-1-4-Inch-Mono-Closing-Trs-Guitar-Pickup-Pedal-Solder-Pcb-Chassis-Mount-Jack-1.jpg) --> (http://rcl.lt/img_prod/CLI125.jpg)
What would be the optimal trim pot value to replace the 1M output resistor and smooth out any changes in output volume?
By the way, the guts:
(http://img209.imageshack.us/img209/2451/reverbgt.jpg)
100k should be ok ..
testing new web phone thingy,
Yes, Paul (chromesphere) used 100k very succesfully. It will probably be quite happy with a 47k as well. If you've got one to hand, could you try it for us? Thanks.
Yeah 100k was enough for me. At 100k the vol nob hangs around 75% most of the time.
Now the mailbag video is out of the way, I will be uploading the build report and sound demo, and for those thinking about building this effect, a video about the 'mystery' reverb giveaway :D You will want to stay tuned for that one!
Paul
Quote from: quad on May 31, 2013, 06:39:58 PM
It's been a while... but finally I took the time to finish it. I'll get my mic out and record some sounds out of this thing. Oh, right, there's a slight increase in volume indeed. A trim pot on the output will take care of that. :)
(http://img17.imageshack.us/img17/7125/63849907.jpg)
nice pedal man..
not sure on the wallpaper though.. :icon_eek:
;D ;)
Quote from: R O Tiree on June 02, 2013, 03:45:07 PM
It will probably be quite happy with a 47k as well. If you've got one to hand, could you try it for us? Thanks.
Sorry, I had no 47K's at hand, but 100K works just fine. If you trim it down half way, you still get unity, which means 47K should also do the trick (but don't take my word for it, I didn't actually measure it precisely before I closed it off). It's a very tight fit, I'm actually surprised all the stuff made it in. A little bit of force had to be applied on the screws. :)
(http://img254.imageshack.us/img254/9333/reverbfit.jpg)
Build report has been uploaded, hope you like it!
Paul
cool...nice hot water cylinder you got there.. ;D ;)
that switch should be really obvious as a 'bright' boost...... :)
is the fet in the right way....diodes?..i'm sure youve checked...but its easy to miss something like that in the excitement of getting it built..... 8)
Quote from: deadastronaut on June 03, 2013, 10:09:05 PM
cool...nice hot water cylinder you got there.. ;D ;)
that switch should be really obvious as a 'bright' boost...... :)
Yeah pretty funny typo! lol
Oh, i asked about that about a week ago after i recorded the build report. At the start of the sound demo i straighten that out. It was a busted solder joint which i fixed, all working as it should now.
Paul
ok cool. 8)
those boards of mikes are great aen'nt they.....nice and easy to work with,. 8)
Sound demo time :D Next video will be the 'giveaway'. Ill post that in a few days time:
Paul
Quote from: chromesphere on June 07, 2013, 07:54:11 AM
Next video will be the 'giveaway'. Ill post that in a few days time:
No need for that. I just PM'd you my address :icon_mrgreen:
morning guys, just to clarify...
so that 1M to ground on the output has gone now...and been replaced by 47k-100k volume pot?...
: also i was just thinking about having a 'fully wet'' signal (no dry) coming out too...just for an added ambientness option.....thoughts?. :)
Quote from: deadastronaut on June 10, 2013, 04:30:33 AM
: also i was just thinking about having a 'fully wet'' signal (no dry) coming out too...just for an added ambientness option.....thoughts?. :)
YES YES YES. was going to do this to mine. In the way slacker explained here:
http://www.diystompboxes.com/smfforum/index.php?topic=103092.msg916853#msg916853
^ yep, that is exactly what inspired the thought..!. 8)...be a nice option. 8)
Quote from: deadastronaut on June 10, 2013, 04:30:33 AM
also i was just thinking about having a 'fully wet'' signal (no dry) coming out too...just for an added ambientness option.....thoughts?. :)
^nice idea! Wonder if theres enough room for one more knob in my build :D
oh yeah, heres the 'giveaway'. PCB from R O Tiree. bit of fun I thought, hope you like it.
Is Mike allowed to enter? Mike, do you feel like making yourself a PCB :)
Paul
yeah i'd like the 'fully wet' control too...5 knob 1590b?...hmmmm...easy... ;)
its probably a pretty easy mod....i'm sure mike (R O TREE ) will chime in on that ....hopefully. ;) ;D
Vol pot and DRYMIX pot mods complete. You'll see from the Layout file that the DRYMIX mod is slightly less tidy than my usual OCD would dictate... I've been trying all evening to re-route it without tearing the whole thing apart and starting again. So one of the pads for the DRYMIX pot is away from the other 2... Anyway, here are the new files for v1.5:
Layout (https://www.amazon.co.uk/clouddrive/share?s=ztvRkrj_RlggqQacdMdumA)
PCB Art (https://www.amazon.co.uk/clouddrive/share?s=9pR4kMk2TpUuBmO2HxHJ0o)
Schematic (https://www.amazon.co.uk/clouddrive/share?s=V065ZsL9TWwt2v2wsVa2eE)
Enjoy
Quote from: chromesphere on June 10, 2013, 07:19:28 AM
Quote from: deadastronaut on June 10, 2013, 04:30:33 AM
also i was just thinking about having a 'fully wet'' signal (no dry) coming out too...just for an added ambientness option.....thoughts?. :)
^nice idea! Wonder if theres enough room for one more knob in my build :D
oh yeah, heres the 'giveaway'. PCB from R O Tiree. bit of fun I thought, hope you like it.
Is Mike allowed to enter? Mike, do you feel like making yourself a PCB :)
Paul
Cool contest, Paul!
Thanks John! I do the odd 'giveaway' now and then on my channel, its a bit of fun. Interesting to see what people are guessing as far as which reverb is which too. Would love to give you more details but dont want to spoil it, ill post on here exactly how i recorded them when its over. :D
Paul
@mike c: nice one mike, blimey that was a squeeze eh.....but a cool option that i should have thought of before....but hey never too late eh. :)
cheers man, your a star. ;)
Quote from: R O Tiree on June 10, 2013, 07:44:27 PM
Vol pot and DRYMIX pot mods complete. You'll see from the Layout file that the DRYMIX mod is slightly less tidy than my usual OCD would dictate... I've been trying all evening to re-route it without tearing the whole thing apart and starting again. So one of the pads for the DRYMIX pot is away from the other 2... Anyway, here are the new files for v1.5:
Layout (https://www.amazon.co.uk/clouddrive/share?s=ztvRkrj_RlggqQacdMdumA)
PCB Art (https://www.amazon.co.uk/clouddrive/share?s=9pR4kMk2TpUuBmO2HxHJ0o)
Schematic (https://www.amazon.co.uk/clouddrive/share?s=V065ZsL9TWwt2v2wsVa2eE)
Enjoy
I'm not sure I understand how you did the dry mix control. I thought lug 1 of the dry mix would go to ground. Like a volume control to kill the dry signal and keep the reverberated signal. Although I'm not very sure if that would even work. I ain't wut yew call book smart :P
Lug 1 goes to Vb. The output from the first opamp stage is biased around Vb, as is the input to the mixer. Therefore, if you bias one end of the pot at Vb as well, that is your "virtual GND". The opamps don't care... and you really want to avoid DC across a pot if you possibly can - that leads to scratchy noises as you adjust the pot. If there had been decoupling caps in between the opamps then, yes, tying that pin to true GND would have been appropriate. I tested it in sim and even a 1k pot works!
I realised earlier today that I had not implemented the Oscillation mod. I've just now finished that.
Here are the new v1.6 files:
Layout (https://www.amazon.co.uk/clouddrive/share?s=jT8GgxvESQMk_dkuqALrjo)
PCB Art (https://www.amazon.co.uk/clouddrive/share?s=snrxyhvwT9Ilvkwjx6vN2o)
Schematic (https://www.amazon.co.uk/clouddrive/share?s=UWOMovEYR3gpz_jOTCXynE)
cool, wasn't the oscillation done by changing 33k to a 22k?..IIRC.
68k ? :)
Quote from: deadastronaut on June 11, 2013, 06:42:00 PM
cool, wasn't the oscillation done by changing 33k to a 22k?..IIRC.
68k ? :)
^ thats what i did
Quote from: R O Tiree on June 11, 2013, 06:00:35 PM
I realised earlier today that I had not implemented the Oscillation mod. I've just now finished that.
Here are the new v1.6 files:
Layout (https://www.amazon.co.uk/clouddrive/share?s=jT8GgxvESQMk_dkuqALrjo)
PCB Art (https://www.amazon.co.uk/clouddrive/share?s=snrxyhvwT9Ilvkwjx6vN2o)
Schematic (https://www.amazon.co.uk/clouddrive/share?s=UWOMovEYR3gpz_jOTCXynE)
Well damn. I already etched the 1.5 board. Is there a way to still do that mod with this board?
Quote from: selfdestroyer on May 22, 2013, 06:18:35 AM
I found by messing with R13 I was able to go from the default feedback with the 33k to some really cool sounding oscillation at 22k. With this tweaked I was able to get infinite-like reverb. I DPDT a 33k 22k 18K to switch it around. I might even look at adding a expression pedal output for R13.. Might be fun.
^ @mike (haveyouseenhim) - The original post from selfdestroyer. Just add a switch to switch over 33k to 22k. That's what I did.
Quote from: chromesphere on June 12, 2013, 03:16:11 AM
Quote from: selfdestroyer on May 22, 2013, 06:18:35 AM
I found by messing with R13 I was able to go from the default feedback with the 33k to some really cool sounding oscillation at 22k. With this tweaked I was able to get infinite-like reverb. I DPDT a 33k 22k 18K to switch it around. I might even look at adding a expression pedal output for R13.. Might be fun.
^ @mike (haveyouseenhim) - The original post from selfdestroyer. Just add a switch to switch over 33k to 22k. That's what I did.
Cool thanks. That's a good thing because I etched the newer boards but I fell asleep and left them in the etchant for SEVERAL hours. Some of the traces are pretty thin. :icon_redface:
Quote from: haveyouseenhim on June 12, 2013, 03:56:43 AM
Quote from: chromesphere on June 12, 2013, 03:16:11 AM
Quote from: selfdestroyer on May 22, 2013, 06:18:35 AM
I found by messing with R13 I was able to go from the default feedback with the 33k to some really cool sounding oscillation at 22k. With this tweaked I was able to get infinite-like reverb. I DPDT a 33k 22k 18K to switch it around. I might even look at adding a expression pedal output for R13.. Might be fun.
^ @mike (haveyouseenhim) - The original post from selfdestroyer. Just add a switch to switch over 33k to 22k. That's what I did.
Cool thanks. That's a good thing because I etched the newer boards but I fell asleep and left them in the etchant for SEVERAL hours. Some of the traces are pretty thin. :icon_redface:
Please don't fry bacon. ;D
I don't leave bacon. In fact, it never even hits the plate :icon_mrgreen: I eat it as fast as I can cook it. If I don't return to the forum it's because I had a heart attack from eating bacon by the pound :icon_eek:
LOL. My father in law used to pour the bacon grease over his toast and never had heart trouble.
Good old bread n dripping we called it . Fat on toast yum
The 68k is in series with a SPST switch and that assembly is in parallel with the existing 33k. Making the switch closes the circuit and the result of 33k||68k is a shade under 22.22k (within 1% of our 22k target). Open the switch and that leaves just the 33k in circuit.
The reason I did it is that SPST switches are cheaper than SPDT ones. Also, a SPDT switch uses up one more pad's worth of real-estate on the board.
With the 1.5 board, you could simply take a pair of wires from the ends of that 33k resistor and then construct that series combo of switch and 68k point to point to achieve the same function.
Quote from: deadastronaut on June 12, 2013, 01:34:46 PM
Good old bread n dripping we called it . Fat on toast yum
Quote from: Jdansti on June 12, 2013, 12:12:12 PM
LOL. My father in law used to pour the bacon grease over his toast and never had heart trouble.
This was my first attempt at time travel......(based on a Jim Gaffigan joke)
:icon_mrgreen: :icon_mrgreen: :icon_mrgreen:
@mike. Of course, series. Para. Gotcha. Man i need more coffe in the mornings cool.
now back to eating lard. , ;)
Ok, I just got a long brick in the mail for my tenebrion reverb, but after seeing the demos for this I think I'm building one of these.
Would anyone be interested if I had a few boards fabbed up? It might take me a bit to get it all right in eagle, but once that is done, OSH park gets me boards pretty quickly.
Pixie dust! Jim is great, I've actually seen him live twice.
Quote from: haveyouseenhim on June 12, 2013, 03:08:05 PM
Quote from: deadastronaut on June 12, 2013, 01:34:46 PM
Good old bread n dripping we called it . Fat on toast yum
Quote from: Jdansti on June 12, 2013, 12:12:12 PM
LOL. My father in law used to pour the bacon grease over his toast and never had heart trouble.
This was my first attempt at time travel......(based on a Jim Gaffigan joke)
:icon_mrgreen: :icon_mrgreen: :icon_mrgreen:
@Mike-How can you stand to eat that without a bag of fried pork rinds? ;D
BTW, If Paul McCartney sees your video, he'll never visit you. Just saying... ;D
Quote from: Jdansti on June 13, 2013, 12:02:17 AM
@Mike-How can you stand to eat that without a bag of fried pork rinds? ;D
BTW, If Paul McCartney sees your video, he'll never visit you. Just saying... ;D
Not a big beatles fan. So no skin off my teeth ;D
I'm almost done withe the reverb....Just waiting on the brick to get here
Quote from: aballen on June 12, 2013, 04:56:21 PM
Ok, I just got a long brick in the mail for my tenebrion reverb, but after seeing the demos for this I think I'm building one of these.
Would anyone be interested if I had a few boards fabbed up? It might take me a bit to get it all right in eagle, but once that is done, OSH park gets me boards pretty quickly.
R O Tiree offers the PCB's for purchase already.
Paul
+1 : mikes boards are the nuts. 1590b sized too.. 8)
Are his boards etched or fabbed?
I can etch one myself... but I really prefer the plated through holes on a fabbed board.
Does anyone here have a belton brick they would like to sell me? Antique Electronics supply has @#$%ed me over again. When I ordered it, it CLEARLY said in green letters "In Stock"
But I got my package today and there was only a switch that I ordered. I called them and they told me it was on back order till mid July. ALL OF MY RAGE! This happened last time I ordered from them. I'm done messing with these people....they have a 100% failure rate. I suggest if any of you order from them to call in the order.
Quote from: aballen on June 13, 2013, 12:14:25 PM
Are his boards etched or fabbed?
I can etch one myself... but I really prefer the plated through holes on a fabbed board.
They are not plated through, but they are soldermasked.
Nevermind... I talked with the supplier and changed it to vertical mount (which I can make work) and I got them to send me a free shirt after a little fuss. First time they messed up it was ok,these things happen, but the second time the exact same thing happened and that's not ok. So I got a little compensation :icon_mrgreen:
A quick questions for those of you that have the dry level control. If you turn the dry down completely does the wet signal thats left reach unity? If it doesn't, is there a way to correct it so that it does?
Quote from: R O Tiree on June 11, 2013, 06:00:35 PM
I realised earlier today that I had not implemented the Oscillation mod. I've just now finished that.
Here are the new v1.6 files:
Layout (https://www.amazon.co.uk/clouddrive/share?s=jT8GgxvESQMk_dkuqALrjo)
PCB Art (https://www.amazon.co.uk/clouddrive/share?s=snrxyhvwT9Ilvkwjx6vN2o)
Schematic (https://www.amazon.co.uk/clouddrive/share?s=UWOMovEYR3gpz_jOTCXynE)
How much for 2 of these PCBs including shipping to Ireland please?
Quote from: jmasciswannabe on July 02, 2013, 02:22:45 PM
A quick questions for those of you that have the dry level control. If you turn the dry down completely does the wet signal thats left reach unity? If it doesn't, is there a way to correct it so that it does?
sorry haven't had a chance to try the dry mod out yet, but i do have a brick on order to try it out , i will probably breadboard it again and test it .
eventually... :)
I just finished wiring mine and now comes the debugging. I'm not getting any dry signal. When I turn the dry pot up all i get is the faintest barely audible distorted dry signal that almost sounds like white noise. In the morning I'll try putting pin 1 of the dry pot to ground instead of virtual ground and see if that makes any difference.
Edit I couldn't wait till morning. I tried lug one to ground and got the same thing. Any suggestions? Has anyone built it with the dry mod yet?
Anybody? :icon_cry:
haven't tried it yet mike...
Quote from: haveyouseenhim on July 19, 2013, 02:49:57 AM
Anybody? :icon_cry:
I adapted this dry control to a similar circuit using the above described method and it worked fine, except that when I took out all the dry there was a volume drop with just the wet. That's why I was wondering if anyone had completed it on this circuit and the result.
Re: Wet/Dry Mix:
First, keep in mind that I have no idea what the hell I'm talking about. ;)
I looked at Merlin's Equinox reverb and he has the back end arranged like this:
(http://i1160.photobucket.com/albums/q485/jdansti/DB912F08-867D-442B-8DC3-9251CD474944-25200-00001DA236D16366.jpg)
A couple of differences are that he is using a TL072, and he doesn't have a JFET on the output from the reverb chip. I'm thinking that there shouldn't be any major differences between the outputs of the bricks vs PT2399.
It may not work for this application, but it looks like an easy mod to try.
Hey guys, I just did up a bom/component list so I can refer quicker (making a few) - am I blind or is there no R10?
Guessing it might have dropped out from an earlier schem
Sorry, double/ triple post. Getting used to tapatalk... :-\ :icon_redface:
Quote from: pastiche on August 09, 2013, 08:06:08 PM
Hey guys, I just did up a bom/component list so I can refer quicker (making a few) - am I blind or is there no R10?
Go with the schem and layout I sent you in my email. There is no R10 in there. I suppose it was inevitable that differences would creep in between deadastronaut's original diagram and the various versions of my layout as suggestions from forum members were incorporated.
Here is the BoM generated from ExpressPCB/SCH:
CapacitorsC1 100n
C2 100u
C3 47u
C4 47u
C5 22n
C6 100p
C7 100n
C8 1n
C9 1u
C10 47n
C11 22n
C12 100n
C13 100n
ResistorsR1 10k
R2 10k
R3 1M
R4 2M2
R5 10k
R6 22k
R7 10k
R8 10k
R9 10k
R11 33k
R12 10k
R13 33k
R14 1M
R15 8k2
R16 1M
R17 68k
Semiconductors/ICs D1 1N4148
D2 1N4001
Q1 J201
U1 LM78L05
U2 TL074
U3 BTDR-2H
ControlsDAMP 10kB pot
DRYMIX 10kB pot
FDBK 10kB pot
RVB 22kB pot
VOL 47kB pot
OSC SPST switch
SW1 SPDT switch for Bright/Warm selection
Hope this helps.
@self destroyer:
so you verified my pcb layout. this one? CME reverb.
http://www.diystompboxes.com/smfforum/index.php?topic=101126.msg897116#msg897116
any know if it would be possible to add an effects loop on this verb? i'd like to play around with adding stuff to the wet signal a bit. maybe get into some modulated reverb territory.
It might need another pair of buffers? Emitter followers might be best - small footprint and small parts count?
What about adding some sort of modulation? Would any of the pt2399 modulation circuits work in here somewhere?
anyone tried the wet/dry mod yet?
ive added a volume to it, much better... 8)
Quote from: deadastronaut on September 15, 2013, 10:36:11 AM
anyone tried the wet/dry mod yet?
ive added a volume to it, much better... 8)
I tried it but it's not working for me. I'm only getting wet signal with the faintest distorted dry signal in the background.
Hey guys,
I would love to get a board for this pedal. Maybe even a couple. I would rather buy one than etch it. Anyone making these that could sell me a couple?
Thanks!
Jason
Quote from: mtbrider405 on September 18, 2013, 09:57:14 AM
Hey guys,
I would love to get a board for this pedal. Maybe even a couple. I would rather buy one than etch it. Anyone making these that could sell me a couple?
Thanks!
Jason
R O Tiree is making them. Complete with an etch mask
Thanks haveyouseenhim,
that is what I thought. I sent him a PM, or thought I did, not sure if it went through.
R O Tiree, if you see this would you mind PM'ing me about getting a couple boards to me?
Thanks guys!
Jason
i sent him a pm a couple days ago as well. i'm guessing he's just tied up at the moment. i'd love to get a board for this too.
Quote from: deadastronaut on September 15, 2013, 10:36:11 AM
anyone tried the wet/dry mod yet?
ive added a volume to it, much better... 8)
If you take a look at what IC2D is doing....I believe you have a wet/dry mix already going on with the "reverb" control.
I C2D is mixing the dry signal and the wet signal and sending it to the output. The amount of wet signal is controlled by the "reverb" control.
I believe that if you changed the reverb pot to a larger value you would cut even more reverb signal resulting in....more dry signal making it through the output mixer.
The original value of the pot was chosen so there would still be an certain amount of reverb left in the mix even with the control all the way counter clockwise.
Hi, is there an alternative to the LM78L05?
I can't seem to find it on any of the three stores I order from here in Germany.. ( Musikding.de uk-eleczronic.de & banzaimusic.com )
Thanks!
Drop the LM.
Search 78L05.
Ah, perfect. Thanks!
One more stoopid question..
The two switches:
SPDT = On/off/On or just On/On ?
Quote from: therealfindo on September 20, 2013, 02:37:02 PM
Ah, perfect. Thanks!
One more stoopid question..
The two switches:
SPDT = On/off/On or just On/On ?
On/On
had a thought last night about a 'tails' switch option... :icon_idea:
implementation?...any ideas?..just a thought...would be a nice option though.. 8)
edit:
found this from merlin....who i asked ages ago, but never implemented it.
http://www.diystompboxes.com/smfforum/index.php?topic=95632.msg829071#msg829071
So going by merlins suggestion...which i can't visualize..need more coffee.. ::)
how is the dpdt wired...to achieve 'optional' tails...with TB.?
(https://dl.dropboxusercontent.com/u/7464107/REVERBTAILS1.jpg)
Quote from: deadastronaut on September 25, 2013, 08:32:27 AM
had a thought last night about a 'tails' switch option... :icon_idea:
implementation?...any ideas?..just a thought...would be a nice option though.. 8)
...
how is the dpdt wired...to achieve 'optional' tails...with TB.?
I'm a total beginner.. but.. wouldn't the idea be that the switch would somehow mix the reverb output into the bypassed output? The reverb is not getting any input, because of the 3pdt, so wouldn't that just be tails then?
What length brick are y'all using in yours? I'm thinking medium, but that long brick is calling my name...
Looooooooooonnnng.. btdr-2h. ;)
Quote from: deadastronaut on September 25, 2013, 08:32:27 AM
had a thought last night about a 'tails' switch option... :icon_idea:
implementation?...any ideas?..just a thought...would be a nice option though.. 8)
If you want tails then you need to set it up for buffered bypass and when you switch it 'off' you just lift the input to the reverb brick (but not the regeneration).
^ i asked ian (slacker) and he came up with this idea...
(https://dl.dropboxusercontent.com/u/7464107/reverb%20tails%20idea.jpg)
haven't tried it yet though...
but i'm open to suggestions...electronic switching ?.. :icon_idea:
That look's like it should work - certainly work a try.
Small caveat with that idea for anyone who's interested is that in "tails" mode and bypassed the drymix and volume controls will set the level of the bypassed signal. The volume control probably won't be much of a problem if you're just using it to balance the level compared to the true bypassed level but it's possible to set drymix to 100% wet leading to no bypassed signal. Might be fine depending on how you use the reverb.
It really needs some way to bypass the drymix pot when bypassed, I'm thinking you can just lift the end that goes to Vb or better switch a large resistance in there so that the pot is effectively turned all the way up when bypassed. I can see a way to do this using just the existing 3PDT, but it means losing the LED, unless there a way to rewire it to keep the true bypass/tails option and use millenium bypass for the LED?
Otherwise it's electronic switching time.
i don't want to lose my beloved led ;D
hmmm electronic switching?...
Since you have kind of a buffered in and out anyway, you could just stick a FET in the path from the input buffer to the brick and switch that? Like, fer example, Merlin's "Small Time (http://www.valvewizard.co.uk/smalltime.html)" delay? And you get to keep your LED!! :icon_cool:
hi marc: care to edit my schemo with that idea?...then i'll bread it up and try it...cheers man.
(https://dl.dropboxusercontent.com/u/7464107/REVERBBBo.jpg)
PMed... (no access to FTP from work...)
from marc, ^ got it...here ya go.
(https://dl.dropboxusercontent.com/u/7464107/marcsswitchingidea.jpg)
so this would be buffer bypass, with tails?...but not true bypass too?..
i'm looking at having a tails on/off toggle...but a 3pdt TB too..
Quote from: deadastronaut on October 02, 2013, 05:07:32 AM
so this would be buffer bypass, with tails?...but not true bypass too?..
Er, yes. :icon_redface: After all that effort... ::) :icon_biggrin:
Or you go the whole CMOS-switching route. Lots of handy hints at Geofex. I'll leave that one to you, Rob!
And I'm *not* skiving. I'm on a "coffee break". ;D
lol...i'll give it a go man, thanks for that . 8)
You can add Merlin's tails/TB switching to Marc's thing basically the same as for my idea. Still leaves you with the drymix issue, a second fet could take care of that.
^Still leaves you with the drymix issue, a second fet could take care of that.
IC2d is a diff amp, so as I read it, the reverb pot does not affect the dry level, but just mixes in the wet - I might be wrong though (again).
The volume pot will be in the circuit. Merlin got round this in the Small Time by leaving the dry level at unity gain, and by omitting a volume pot.
@sam: yep reverb level adds the wet....i will be adding an overall vol pot on the out.
@ian: another fet?..
@Sam you're right the reverb level doesn't affect the dry signal. Actually it does a bit but not enough to worry about, it plays a part in setting the gain for the non-inverting side.
The schematic Rob sent me is different to the one Marc posted though and also has a volume control for the dry signal, see my hacked schematic a few posts back.
^The schematic Rob sent me is different to the one Marc posted
Gotcha. In that case, a second FET switch between the dry mix lug 1 and Vref would do the trick wouldn't it?
Yeah, I think so.
oops!...sorry guys, cross schemo's.. :-X
can we go with the schemo marc posted...as that is the one i have my verified pcb layout for...and intend to tweak/re jig....
That would make things a little easier. Do you want a true bypass option? It is do-able - I set up my Small Time delay like this...
Quote from: samhay on October 02, 2013, 08:25:23 AM
That would make things a little easier. Do you want a true bypass option?
cool..yes please!.. :)
Transplant my mods into that schemo, tweak the dry side for unity gain, job done :)
Transplant those. 2 resistors and switching from the schemo a few posts back..?...thats it?
If you want to use the FET switch, then I think this will work.
The 3PDT is the foot switch and the DPDT a tails toggle switch.
(https://dl.dropboxusercontent.com/u/11996927/Tails_switch.jpg)
cheers sam, your a star man., i'll bread this up today after a few of mrs astro's chores ::)
and try it out ...so the led on the fet will be the on/off led...cool.
back later.. 8)
Quote from: deadastronaut on October 02, 2013, 03:45:09 PM
Transplant those. 2 resistors and switching from the schemo a few posts back..?...thats it?
Yep, that's it, don't forget the extra cap before the resistors.
ahhh i'm lost.. ???
this... :1
http://www.diystompboxes.com/smfforum/index.php?topic=101126.msg937874#msg937874
...
or this...with this.. :2
http://www.diystompboxes.com/smfforum/index.php?topic=101126.msg938031#msg938031
http://www.diystompboxes.com/smfforum/index.php?topic=101126.msg938146#msg938146
i was going with this schemo as i have a verified pcb layout of this schemo that i could just tweak a little... :)
http://www.diystompboxes.com/smfforum/index.php?topic=101126.msg938023#msg938023
The switching scheme I posted should work for any pedal that uses a buffered bypass and a FET switch (pulled high) to turn on the effect.
If I have not misremembered, and have drawn it correctly, I used this to do a tails/bypass switch on Merlin's Small Time delay. It should work on the schem that Marc posted - http://www.diystompboxes.com/smfforum/index.php?topic=101126.msg938031#msg938031
I should probably point out that this does not ground the effect input or output in bypass. This shouldn't be a problem with these effects, but you may wish to check.
Oh, and yes - you use the LED off the FET switch as your indicator.
Apologies if I've caused any confusion. I would either go with option 2, the Marc and Sam collaboration.
Or take my mods from option 1 and splice them into into your schematic below.
Quote
i was going with this schemo as i have a verified pcb....
http://www.diystompboxes.com/smfforum/index.php?topic=101126.msg938023#msg938023
Either one does the same thing, the choice is yours, as they say.
Just to muddy the water a little more. Ian's approach is nice, as it doesn't use any more active components. You could splice this into your existing PCB in the same way...
no apologies needed...its my brain not yours.. ;D
so like this ..(ians switching)...should there be a cap before the 4.7k's?.
(https://dl.dropboxusercontent.com/u/7464107/reverbwithtail1.jpg)
Yeah, I would put a cap before the 4k7s. It will probably work without a cap but will likely pop like crazy.
... and you would be back to a 'cool reverb apart from switch spdt 'pop' issue'
Ha ha
Lol... Pop pickers,.. ;)
Great project !
whether the pop issue is still there... an idea is to implement the switch as per Pinnacle Deluxe boost switch (jfet switch with bipolar cap).
Hope to try it soon and let you know.
byeee
okey dokey...i re-jigged my layout according to mods....looks right to my eyes?.
pink cap value?...
(https://dl.dropboxusercontent.com/u/7464107/reverbjigged.jpg)
Pink cap wants to be big enough to not interfere with any tone shaping the 10k(2 x 4.7k) 22n cap combo are bringing to the party. Try 100n or bigger.
cheers ian, i'll socket that cap then. ;)
When not bypassed, the pink cap is in series with the 22n cap on the other side of the two 4k7 resistors. You may want to make this bigger too...
ok, cheers sam, i'll socket them both then..
etching the pcb now..(couldn't be arsed with breadboarding it up again.. :)
;)
If you like how it sounds now, then try both caps at 47n.
yeah i love how it sounds now...okey dokey....think i'll socket em just to mess with anyway..
pcb etched...drilling. ;)
You have a ~700 Hz HPF into the reverb (22n/10k) as per the data sheet. 2 x 47n and 2 x 4.7k will get you essentially the same.
cool, cheers sam, 8)
pcb drilled..populating... ;)
Quote from: deadastronaut on October 04, 2013, 10:11:15 AM
cool, cheers sam, 8)
pcb drilled..populating... ;)
Sweet! Looking forward to hearing how it goes.. I'm going to start populating the board I etched really soon, so still time to make this mod if it works - Good thing I decided on the BB size box, so there's room for another switch ;)
^ did you add the 2 4.7k's and 2 47nf's on your pcb then?...
tip: socket the 33k (the one under the 100uf) ...so you can have the oscillation option too.. ;)
populated...
now mass wiring.. ::)
well i didn't get time to wire it up at the weekend thanks to mrs astro's wanton need to go to the space station ..again. :icon_rolleyes:
but regardless of the van allen belt radiation burns and severe muscle wastage and being beaten by small meteorites travelling at over 30,000mph whilst trying to urinate in my suit i'm on it today... :)
beep....................................beep.........................................
ok, wired everything up as per diagram/s...
no reverb at all... :icon_eek:
the bright/warm switch is working, volume working,
3pdt working....there is a massive vol jump with the tails dpdt when on....but ok when off..
(only thing ive left off is the led for now.....)
hmmmm.... :(
(https://dl.dropboxusercontent.com/u/7464107/reverbtails111.jpg)
Just had a peak at the layout and the connection to pin 3 of the brick looks wrong, you have it from the inverting input of the opamp not the output.
You will get a volume diff in tails mode unless you match the dry signal level with the true bypass level.
oh f................... :icon_evil:
yeah i see what ive done... ::)
son of a @#$%ing mother @#$%ing @#$%er b.......
hmmmm....well spotted man....
edit:
so lookng at my old layout, if i cut the jumper ( above 12-10 pins ) and take it to pin 8 instead should be ok yeah?..
like this...
(https://dl.dropboxusercontent.com/u/7464107/motherfu.jpg)
Looks groovy to me.
okey done that, we have reverb...yay!!!..
however...
tails switch works on/off..
but i still have reverb when bypassed on the 3pdt....i thought it would trail off reverb when i hit the 3pdt and be able to play clean over the trails....weird.
face palm, I'm a buffoon, I never noticed until now that your feedback signal is taken from after the wet and dry are blended, so even if you kill the input, the dry signal still gets fed into the brick via the feedback pot so you'll still get reverb.
Let me think about it.
Bugger, I should have spotted that too - sorry.
Will have a think about it as well. It is getting a bit tricky, as we don't have any switch lugs left...
:'(
i knew i should have just built an AB BOX.. ;D
What happens if you jumper R17?
You could try taking the feedback from lug 3 of the "reverb" pot instead, that will solve the problem but I don't know how it will change the sound and feel of the effect.
You could also connect pin 1 of R13 to the junction of the R17 and R18 instead of to the opamp's input, this will kill the feedback in bypass solving the problem but you might not get much in the way of tails with no feedback.
EDIT: That might be where Sam is going......
jumper R17
remove the 4.7k and jump it...ok i'll try it.
edit:
removed R17, jumpered it..
nope still got verb on bypass..
hmmmm...
think i'm going to have to scrap this build, and go back to the breadboard with this....what a bummer
oh well..
i'll rip this apart and get it up n running as normal/schemo again,...and then try out some tails/bypass options ...
Before you do that, if you set the feedback to minimum, do you still get reverb in tails?
ok, no reverb when feedback is turned all the way down in bypass
Do you get any tails with no feedback? Just wondering if we can get away with killing the feedback when bypassed or if it would be needed to get any decent tail action.
If so, then taking the feedback from the reverb pot is a good idea. In this case, it might be worth making the feedback pot significantly larger.
normal bypass is fine...when on there is full reverb / then bypassed no reverb.
tails switch on : no reverb when feedback is turned down.....but reverb when fully on..
tails switch off: no reverb.
(make the feedback pot 100k/470k/1M?) instead of 22k.
Quote from: slacker on October 07, 2013, 12:58:29 PM
You could try taking the feedback from lug 3 of the "reverb" pot instead, that will solve the problem but I don't know how it will change the sound and feel of the effect.
You could also connect pin 1 of R13 to the junction of the R17 and R18 instead of to the opamp's input, this will kill the feedback in bypass solving the problem but you might not get much in the way of tails with no feedback.
1st option. Your feedback is now only wet signal. This might sound significantly different. You still get feedback in tails bypass.
The feedback pot will now be parallel to the reverb pot, so you may have cross-talk. Making the feedback pot bigger may help with this. Or not. I would only change it if it is objectionable.
2nd option. Your feedback is still the original mix of wet and dry, but you now kill it in tails bypass. This will reduce the tails you here, and may defeat the purpose of having tails. Or not.
I guess that if the tails sound ok when feedback is off, then I would go with option 2. If not, then try 1.
morning...yawn...stretch...yawn....sip of coffee. :P
sitting here making lots of new breadboard jumpers....yawn.. ::)
i may as well just breadboard this up, and go from there..as i'l end up with a butchered pcb anyway..
i'll leave off the hi/lo switch as i know thats fine..
my breadboard is true bypass anyway, so it may make it easier for trying out 'tails' options (depending on the 3pdt switch wiring of course) without loads of wires flying everywhere too...
and i'll try that fet switch lark out ..i take it the fet drain is to the left?.
i'll get it up n running as per my schemo, then try the fet switch out. ....(and try out the wet/dry mix too)
^ i take it the fet drain is to the left?.
That should work.
If you go down the FET switching route, then you can add another FET switch that sorts out the feedback problem. When you have feedback off in tails mode, do you get a decent amount of tails just from the reverb brick?
Quote from: samhay on October 08, 2013, 05:31:00 AM
^ i take it the fet drain is to the left?.
That should work.
When you have feedback off in tails mode, do you get a decent amount of tails just from the reverb brick?
...its a fair bit less ...but still there.....
got it all on breadboard all working fine .... :icon_cool:
now to try the fet...
ok, tried the fet switch..(j201)
the led goes on/off...
when led is on, i get full reverb..
when led is off i get reverb but not as full as when on...
no tails in true bypass though..
Sounds like the FET is not fully closing. A large pull-down resistor from the source to ground might help. Otherwise, do you have any other FETs?
with a j201 the led goes off fully.. (tried 1M-4.7M source to ground)
tried a 2n5457, led didn't go fully off..
tried a 2n5485, led fully off..
when led is on i should get tails?..or off?..
excuse my dumassness but i'm not sure what that fet switch is supposed to be doing?..
The FET is essentially an SPST. When the gate is pulled high, it is on. The LED is just an indicator that the gate is getting 9V. Not sure why it didn't turn off with the 2n5457.
ok, gotcha..
i just read this from merlin, so it should work...hmmmm....maybe if i lose the 10k before the fet...and increase the 22n to 100n as in his schemo...
http://www.valvewizard.co.uk/smalltime.html
edit, tried it no joy,...
Not sure if this helps or hinders, but when I built my Small Time (exactly according to Merlin's schematic - and from which I nicked the FET switching nugget a couple of pages back), I noticed that the J112 was passing just a teeny bit of signal, even when "off". LED was definitely off, but if you "Townshended" the guitar, then you heard a very small signal leaking through. Not had the opportunity to investigate, though - it's since been sold to a mate...
cheers marc,
i'm getting quite a lot of signal through when switched though...without 'townsending it' ;D .hmmm..
when led is on..i get full reverb..
when led is off i still get reverb, just not as full...but there...
FET switches can get a bit leaky with large signals - yours is not staying off.
You could try a BJT instead, but make the 1k gate/collector emmiter a bit larger (10-100k). This isn't very HiFi, and probably won't completely turn off either, but it might play better with bigger signals.
Otherwise, did you try taking the feedback to the junction of the 2 4.7k resistors instead of to the op-amp (-) input?
this is the schemo ive breaded..
http://www.diystompboxes.com/smfforum/index.php?topic=101126.msg938031#msg938031
BJT.. collector base emmiter wired like the fet?.
^BJT.. collector base emmiter wired like the fet?.
yup. RG suggested it a few threads ago, and I have used a bit since then. It can work quite nicely.
http://www.diystompboxes.com/smfforum/index.php?topic=103934.msg929532#msg929532
The suggestion to take the feedback to the junction of the 2 4.7k resistors instead of to the op-amp (-) input was made assuming you still have yesterday's PCB populated. Did you end up canabalising it?
yep..butchered :icon_twisted:
ill try that tranny thing then...will be later as i have stuff to go do... ::)
cheers sam. ;)
well i'm back on it...
tried the (various ) BJT to no avail..
i wonder why the fet switch isn't turning fully off...hmmm..
(btw i tried the wet/dry mix...very nice indeed, thats defo going on it. pure verb and no dry.. 8))
^i wonder why the fet switch isn't turning fully off
This is a known problem with FET switches.
R.G (I think) has written a nice explanation of why large signals can cause JFET switches to leak, but I can't find it at the moment. In general, think about what happens to the drain and source voltage relative to the gate when you put a large varying signal across it...
heres what i have on the fet.. (switch)
D 4.55
G 0.05
S 1.85
Is the source side towards the 22n cap? If it is you need to add a resistor from source to VB, the drain and source both need to be referenced to VB.
hi ian..
yes source towards the 22n..
i just tried various resistors (using my sub box ) from source to vb..no change.
i tried 100k from source,+ 100k from drain to vb no change..
tried 2.2k's also...no change.
strange.. ???
i stuck a 22k from source to vb..
now i have
D 4.55
G 0.68
S 4.55
Just to make sure we're not trying to fix a problem that doesn't exist, are you still using the same feedback set up as before? The Fet switch will not fix that you'll still get reverb when in bypass same as you did with my resistor solution. Any testing you're doing should be with feedback turned all the way down or with the feedback path broken some where.
hi ian.. i'm still using this schematic,
http://www.diystompboxes.com/smfforum/index.php?topic=101126.msg938023#msg938023
but with he fet switch...
i just tried the fet switch with 'feedback'' turned fully down and the switch works...no reverb, and on there is reverb.. :icon_cool:
so were getting there i guess.. :)
Cool.
OK, so if the FET switch works and tails works if feedback is off, then another FET switch shunting the feedback to ground/Vref aught to fix that...
Erm ok....got a diagram ?.. :)
Actually, I was think the wrong way round. It might be even easier - just put another switch (you don't need the LED) in series with the 33k resistor in the feedback loop. When off, the resistance will be large enough that the gain will be ~0.
The beauty of the FET switches is that you can tie the switch end of the 1k gate resistors together, so it only takes 1 pole on the footswitch.
I probably haven't quite painted 1000 words, but do you still need a schem?
Yes please...cant quite see what you mean...cheers Sam .
I think this is worth a try:
(https://dl.dropboxusercontent.com/u/11996927/samsswitchingidea.jpg)
You can then use the switching option I posted a few pages back - worth testing on the breadboard though.
Brilliant, cheers Sam .
ill try it out, and ammend the schemo,
with fthe switching and wet/dry mod...nice one. 8)
just about to try the other fet switch...
heres a clip of the wet/dry mod , fully wet, then half, then off, ....then fully wet again....love it. 8) (10k pot)
https://dl.dropboxusercontent.com/u/7464107/reverbwet.mp3
using 33k( R13) for feedback...i found oscillation will begin around 27K...22K can get a little bit much imo.
ok, tried the other fet switch..
it works, and now i can turn up the feedback pot, then switch to dry...
however the feedback (decay) is considerably cut short....
The new clip sounds grand, and similar to what I am getting. I dig the chord progression too. Is your wet mod the pot that you had in an earlier design?
^however the feedback (decay) is considerably cut short....
Do you mean the tails are not as pronounced when you hit tails bypass?
Quote from: samhay on October 10, 2013, 06:23:37 AM
The new clip sounds grand, and similar to what I am getting. I dig the chord progression too. Is your wet mod the pot that you had in an earlier design?
^however the feedback (decay) is considerably cut short....
Do you mean the tails are not as pronounced when you hit tails bypass?
yeah the tails are not as lengthy when i hit tails...even fully up..
(i'll adjust my schemo in a bit, to show the wet/dry and fets....)the wet/dry was on R O tree's schemo a few pages back.
heres the updated schematic...as i have it on breadboard now.
wet/dry is a 10k pot
(https://dl.dropboxusercontent.com/u/7464107/REVERBWITHTAILS.jpg)
Right - so at the moment, the 2nd FET switch is killing the feedback once you hit bypass. The feedback pot is out of the circuit at this stage, so shouldn't do anything in bypass and the only tails you hear is from whatever is rattling around in the brick.
If you want your tails to also include feedback, then you need to kill the dry signal in the feedback loop. As the feedback is taken from the output of the second op-amp, this will require some faily life-changing surgery.
If you are happy with having wet-only feedback when 'on', then it gets a little easier:
(https://dl.dropboxusercontent.com/u/11996927/REVERBWITHTAILS_sam.jpg)
Edit - schematic updated to remove 2nd FET switch
''life-changing surgery.'' :icon_eek:
lol, well to have tails at whatever setting i guess life changing is the only way to go...seeing as i have it on breadboard anyway....i'm up for it if it solves the issues..
i'll have to attach another breadboard though as i'm running out of space.. ;D
One other thing - the 2nd FET switch becomes redundant at this stage and you don't want to switch it off in bypass.
just a quick example of the 'tails' i have at the mo..
first clip...natural decay...1 2 3 4....decay................
second hit tails switch on ..1 2 3 (switched on 4)...
just to show how it cuts the decay.
https://dl.dropboxusercontent.com/u/7464107/TAILSTEST.mp3
i was just having a nose about at ians echobase 'tails ' etc..
a guy here has a tails/feed/flashback mod without a 4066 etc...could this be applied to the reverb ...what do you think?..
http://www.diystompboxes.com/smfforum/index.php?topic=60662.msg791797#msg791797
I can hear why you want some feedback in tails mode.
Your new schem is missing the 10k resistor to C5. Is that still there? In the Echo Base, the feedback is mixed with the dry signal (which is lifted in bypass) just before the PT2399. This is similar to the latest schem I posted.
The "tails/direct/flashback mod" could be done if you want to go down the buffered bypass only route, no true bypass option. Or you could go with flashback/tails/true bypass.
For those playing along at home flashback is the opposite of tails, the input of the delay is always connected bypass disconnects the output. Direct disconnects both the input and output so the delay behaves in the same way as if you true bypassed it.
To be honest for a reverb I'm not sure how much use the flashback option is, I suppose for over the top ambient reverbs it might be good, you can kick it in and immediately get a big wash of sound, for short reverbs I'm not sure you'd notice the effect.
morning!.. ;D
@sam: corrected schemo..well spotted.
(https://dl.dropboxusercontent.com/u/7464107/REVERBWITHTAILS.jpg)
@ian: i'm beginning to think buffered might be the way to go then..as long as i can have the long oscillating tails ...
'' Or you could go with flashback/tails/true bypass. ''....hmmmm...
Let's think about where the signal goes in this circuit (x's are where you have FET switches; sorry about the crappy ascii art):
In -> buffer --------> mixer1 ---> out
| /\ |
x1-| | |-x2
\/ | \/
mixer2 -> brick --| |
/\ |
|----------------------|
In your original tails mode, you killed dry signal going to mixer 2 at x1. However, when you had feedback up, the signal from mixer 1 was still being fed into mixer2 via the feedback loop.
If you lift the feedback loop in tails bypass (at x2) then you don't have any signal from mixer1 being fed to mixer2. This keeps dry signal out of the brick, but removes much of the 'tails' effect, as you don't have any feedback anymore. I am not sure how buffered bypass would help.
One options is like this (the latest schem I posted):
In -> buffer --------> mixer1 ---> out
| /\
x-| |
\/ |
mixer2 -> brick --|
/\ \/
|-----------------|
Now, we split the wet signal from the brick. One output goes to mixer 1, the other to the feedback loop and is mixed with dry signal at mixer2. In tails bypass, you kill signal from the input buffer only. The feedback loop is still active, but now is not mixed with dry at mixer2.
The feedback will sound a little different, as you are not mixing it with dry signal (via the dry and reverb pots) at mixer1. However, you might find this works better this way as the feedback will be more usable at low reverb settings.
arghhhhhhhh my head hurts trying to think of/realize it... :)
You mean my terrible diagrams didn't help?
It should be minimal work to try the last schem I posted on the breadboard.
lol. yeah...
this one you mean?
http://www.diystompboxes.com/smfforum/index.php?topic=101126.msg939394#msg939394
yup - another one of my masterpieces.
Quote from: deadastronaut on October 11, 2013, 10:59:49 AM
http://www.diystompboxes.com/smfforum/index.php?topic=101126.msg939394#msg939394
hi sam, just tried that ^ but it cuts off the decay very abruptly still... :)
Hmm, that's puzzling. What happens if you move R2 to in between the FET and C5?
yeah thats the same,
( it has cut the reverb decay/feedback from being full when on..only short decay)
as a note i decreased the 33k feedback resistor right down but it will not go into oscillation like usual..
OK, need to have a think about this.
Can you do a quick experiment Rob. Using this schematic http://www.diystompboxes.com/smfforum/index.php?topic=101126.msg939391#msg939391 (http://www.diystompboxes.com/smfforum/index.php?topic=101126.msg939391#msg939391) but without the Q3 switching so you aren't killing the feedback in bypass, if you set it to 100% wet on the wet/dry do you get good tails when you bypass it, obviously you'll get no dry signal in bypass but does the reverb tail off nicely?
If that works Ok the easiest thing to do might be to add a bypass around the whole thing, that way you keep all the functionality and sound of the pedal but you can have tails, just means another opamp or two.
Actually I've just had a cunning plan, I'll be back........
ok baldrick ;D, , i tried it fully wet, and yes i got excellent trails with the fet switch off......(and no original signal as to be expected..)
Exellent. Here's the cunning plan, using that same schemo try this mod to the Q3 switching.(http://img.tapatalk.com/d/13/10/13/amejanep.jpg)
This adds a delay before the fet turns off when you bypass it allowing feedback to carry on for a while. Experiment with different values for the 100k for different delay times. Simulator shows some distortion but it might work ok.
aha...nice one man. neat trick..
cool, that works, i used a 1M...and it gets the same decay/trail as when on/off...brilliant. 8) 8) 8) 8) 8) 8)
so now we have...
(https://dl.dropboxusercontent.com/u/7464107/REVERBWITHTRAILS666.jpg)
one thing though...
when i have wet/dry set to dry ...and switch to tails, i have reverb on guitar (not as much as full reverb) while tails are going on....then when tails finally die off, the guitar signal becomes dry....
Cool, nice to hear it works. Yeah unfortunately you're going to get that because then your feedback signal includes the dry signal, the only way round that is to take your feedback from somewhere before you mix the dry back in. Or bypass the whole shabang, that will definitely work, it feels like a horrible bodge though.
Have you got a datasheet for the brick you're using, the one I can find online appears to be for a different version?
Heres the datasheet for he btdr-2h...
http://www.mammothelectronics.com/v/vspfiles/assets/images/btdr.pdf
slacker - nice idea.
Rob - This is proving to be even worse than preventing a little pop.
With respect to my idea, the brick may be struggling with the 10k load of the feedback pot. You could try increasing this to 100k (which is what I have on the breadboard with my design, but can't remember if this is because 10k didn't work right). The output of the brick will be ~ half, so dropping the 33k resistor was a good idea.
Quote from: samhay on October 13, 2013, 09:05:05 AM
slacker - nice idea.
Rob - This is proving to be even worse than preventing a little pop. yeah i know. :icon_mrgreen: :P
With respect to my idea, the brick may be struggling with the 10k load of the feedback pot. You could try increasing this to 100k (which is what I have on the breadboard with my design, but can't remember if this is because 10k didn't work right). The output of the brick will be ~ half, so dropping the 33k resistor was a good idea...just tried a 100k pot, and messing with the 33k...no difference really..
''Or bypass the whole shabang, that will definitely work, it feels like a horrible bodge though.''
may have to be the way to go...hmmm... :)
Quote from: samhay on October 13, 2013, 09:05:05 AM
slacker - nice idea.
Cheers. shame it didn't quite work, handy little snippet to have around though :)
The reason taking feedback from the output of the brick doesn't work too well could be down to phase. The datasheet doesn't say but I assume the output is notionally in phase with the input, as much as it can be for something like reverb. The current scheme inverts the output of the brick and then inverts it a second time before feeding it back in, so it's in phase. Taking the output from the brick and just feeding it back through IC2C inverts it so it's out of phase.
Give this a try, this hopefully gives "in phase" feedback. The "Fback" resistor sets the max feedback level start with a jumper and adjust to taste, assuming it works. Might not need the new "R6" try it with and without, with it R19 might need tweaking to keep the levels right.
(http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=49807&g2_serialNumber=1)
If this works then we're back where we were about 4 pages ago, you just need a second fet switch to lift "dry/mix" from VB in bypass.
Fingers crossed ;D
slacker - you are quite right, I had forgotten about the inverting op-amp.
hopefully that will do the trick.
cheers ian and sam for going way beyond the call of duty to help solve this bugger.. 8)
i'll give that a go a little later, and yep, i'll have my fingers crossed ;)
back in a bit.. :)
No worries Rob.
Sorry for not catching a few, rather obvious in hindsight, issues sooner.
@ian, that works and we now have tails with clean guitar..... :icon_cool:
however :P... immediately i noticed the reverb decay is dramatically cut short. even on max feedback...
and feedback pot is doing nothing. :)
What value is the feedback resistor you chose?
morning.. :)
i tried from 100r - 4.7M. (using resistor sub box)
i also tried lowering R5 but it distorted too much.
I'm confused, even if this was an impedance issue, then I would expect the feedback pot to do something - just less than before.
i'll double check it over...i wondered why the feedback pot did nothing too..
back in a bit..
Yeah the feedback pot should at least do something, unless there's something I'm missing what I've done should have positive gain with pot turned up so you should get oscillation.
nope.. just checked,
no change on fb pot at all.....i swapped it for another too..checked connections.
i even tried the 22 to vb, no difference....weird. :P
I'm stumped, I don't see how this can't work. Have you tried taking feedback straight from pin 5 or 6 of the brick?
just tried that..no difference..on 5/6
just to confirm....pin 10 has a 1M to VB..and pin 10 also goes to 100nf....100k pot>resistor>100nf...>..to junction of 10k pot/10k resistor..
thats how i have it..
just checked my Vb's..all sitting nicely at 4.55v.
from pin 10 to the 100nf i have 4.5v...pot side of 100nf is 0.00v.....resistor>100nf..output 5/6 side of 100nf is 4.5v..
measured resistance on pot..working fine..
Yeah that's it. I think we need to do some testing, disconnect C12 from the junction of the 10k and 10k pot, and instead of plugging your guitar into the input of the pedal plug it into C12, this should then give you wet reverb on the output. The pot should control the level. Does that work.
hold on...
aha...dumbass that i am... ::) (just slapped myself and the cat ;D.)
i still had a wire from pin 10 to vb....whilst connecting the 1M from pin 10 too... :icon_redface:
so now we have oscillation again....and switch works....but cuts tails off quick still. (even at oscillation)
Yaaahhhhhhhhhhhh, thank fook for that, I was just about to drive down to the big smoke and throw the fecking thing through the window for you ;D
Does adding the extra 22k help with the tails? If it does you could try making it smaller which will increase the gain.
ha ha your welcome to throw my cat out too... ;D
tried the 22k, i just turned my mixer up and there is a faint hint (but noticable ) of verb when bypassed (plucked hard) (fet switched off)
if i put that 22k lower it brings out more verb...and tails oscillation. (fet switch off)
if i turn feedback right down there is no background reverb at all.....
tails are better but still unaturally decay quick when switched.
heres a little sample , fully wet, with delay...
ahhhhhhh chillll..... 8)
https://dl.dropboxusercontent.com/u/7464107/deadastronaut%20wet%20reverb%2Bdelay.mp3
That doesn't half sound ok, and it sounds like I missed some fun - hope the cat is still talking to you Rob.
Am I correct is now assuming now that: everything works; it will oscillate with feedback at max; but the tails still don't sound great?
^ yep, full oscillation 8) , but tails still too short... :P
the cat is fine now that we have oscillation , but she's stil quite concerned about the economy and the U.S shutdown at the mo. :)
Hey,
Liking the look of this tails mod, will keep an eye out for it.
In the meantime I've attempted a vero layout, there are standing resistors which I'm sure some of you will dislike and to be honest I'm not sure if some of the caps will fit in the spaces. I'm pretty certain there'll be a few mistakes, especially getting lugs 1 & 3 muddled on the pots :icon_redface:. If someone could give it a look over for me I'd really appreciate it.
I used RG's Rev1.6 schematic and I've included the DIYLC file if anyone wants to tinker with it.
https://www.dropbox.com/sh/80zyw6uyxoi9xh8/-6SQw_IlCN
Cheers,
Marcus
Quote from: deadastronaut on October 14, 2013, 07:24:36 PM
^ yep, full oscillation 8) , but tails still too short... :P
the cat is fine now that we have oscillation , but she's stil quite concerned about the economy and the U.S shutdown at the mo. :)
Nothing like a bit of financial uncertainty in the global markets to unsettle the local feline population.
I have had a bit of a think about the IC2c - the op-amp mixer into the brick. I think the gain of the feedback signal will get a bit uncertain when the FET closes as it will become maximally 22k / (22k ||FET on resitance) and the frequency response will get really strange. However, this should still alow the wet signal to pass though, so I am like always, a little confused.
Does the oscillation when feedback is at max stop if you switch to tails mode?
Quote from: samhay on October 15, 2013, 07:28:28 AM
Quote from: deadastronaut on October 14, 2013, 07:24:36 PM
^ yep, full oscillation 8) , but tails still too short... :P
the cat is fine now that we have oscillation , but she's stil quite concerned about the economy and the U.S shutdown at the mo. :)
Does the oscillation when feedback is at max stop if you switch to tails mode?
yep it sure does...
That last clip dounds great, we're close now I can feel it. As an experiment to test Sam's thoughts if you just stop playing, leaving the effect engaged, do you get good tails? If you do then I think Sam's right and we need to dick about with the mixer a bit.
I was going to suggest the same.
As an aside, I find that with the design I have on the breadboard, it gets louder as it oscillates until the brick starts clipping. This sounds about as nasty as clipping can get, and very different to op-amp clipping. Does this design do this too?
hi ian,
yes massive trails when on as normal ....but bypassed (fet) not so ...gets cut short.
@sam: it can get nasty/distortion...but if careful (220k as FB resistor) its very controllable now..
OK cool.
So you have a 220k feedback resistor, and 100k feedback pot and R6s are both 22k?
Edit - I have an idea. We could place the FET in the feedback path of the op-amp and remove the 22k to Vb (but leave a 10k or 22k in the feedback loop parallel to the FET). When the FET closes, the gain of the dry signal -> 0, while the wet should be ~ 1. You will probably have to reduce the 220k feedback resistor to ~100k.
Take a look at Merlin's Glassblower for an example of the FET switch used as suggested: http://www.valvewizard.co.uk/glassblower.html
Quote from: samhay on October 15, 2013, 10:25:28 AM
OK cool.
So you have a 220k feedback resistor, and 100k feedback pot and R6s are both 22k?
Edit - I have an idea. We could place the FET in the feedback path of the op-amp and remove the 22k to Vb (but leave a 10k or 22k in the feedback loop parallel to the FET). When the FET closes, the gain of the dry signal -> 0, while the wet should be ~ 1. You will probably have to reduce the 220k feedback resistor to ~100k.
Take a look at Merlin's Glassblower for an example of the FET switch used as suggested: http://www.valvewizard.co.uk/glassblower.html
morning, yep 220k/100k fb pot, both R6's 22k.
edit : like this?.
(https://dl.dropboxusercontent.com/u/7464107/samhaytails.jpg)
so the fet switch would be between pins8/9 ( with the 100pf/22k) with a 10/22k between 8/9 also....fb resistor to 100k.?...sound right?
@marcus: mmlee: hold fire for now.. ;)
something like this:
(https://dl.dropboxusercontent.com/u/11996927/tmp_16oct13.jpg)
ahhh right gotcha!..i'll give it a go. ;)
so this then..
(https://dl.dropboxusercontent.com/u/7464107/samhaytails1.jpg)
Not quite - you still want to take the feedback from the brick's output, like in the previous schem, but you want the feedback to go to the (+) input of the op-amp.
HOLD ON...ithink i have it..
schemo above corrected?..
bingo.
First things first, but you may need to play with the feedback resistor to get oscillations again.
righto... back in a bit..
ok, tried that.
now when fet switch (led is on) i get clean signal , no reverb. ( not even a hint, which is good)
when switch led is off i get full reverb...(oscillations still good)
but tails still cut short...when switched
So it stops oscillating at max feedback when the tails is engaged? I will have to go back to scratching my head for a bit.
I guess on the bright side, we are learning rather a lot about FET switching.
yep, it dies off pretty quick, even at oscillation.
OK, this shouldn't be that hard.
With the switch open, we have a gain of 2.2 for for the dry signal (R6/R9) and a max of < 1/2 for the wet ( 100k/220k + whatever voltage divider effect we have between the feedback and reverb pots).
With the switch closed, we have a gain of nearly 0 for the dry signal and the wet should be unaffected if there is no resistance from (-) input to ground.
What are we missing? Do we need to get both of these to a gain of ~1?
no idea.. ???
its strange how it cuts the tails quickly...but smoothly fades off...as if a volume pot is being turned down.
its the turny down bit thats bugging.. ;D
meanwhile a little vid demo, i couldn't resist it,.. :)
If you increase the value of the resistor to the FET's gate, does it behave any differently?
nope.
tried from 100r-4.7M
Quote from: samhay on October 16, 2013, 12:26:51 PM
and a max of < 1/2 for the wet ( 100k/220k + whatever voltage divider effect we have between the feedback and reverb pots).
I think you're looking at it wrong, R19 and C5 are connected to vref as far as signals going in the + input are concerned so the the gain for the feedback signal is 3 1+(R6/R19), assuming the R19/C5 combo lets though all frequencies of any interest. This is ignoring the divider effects of the feedback pot etc.
When you close the switch, for the feedback signal, the gain from the opamp drops to one, so the overall gain is 1/3 of whatever it was with the switch open.
My previous idea suffered the same problem to a lesser extent, the gain of the feedback signal went down in bypass.
This setup but with something like my original resistor switching idea should work better because then the gain will go up in bypass.
slacker - you're quite right.
Edit - I think the easiest solution might be to do something a little different. Of course, I may be wrong yet again.
If we go back to the original plan of shunting the dry signal to ground, we can run the feedback into the (-) input of the op-amp via an inverting op-amp stage so that, hopefully, we don't have the phase issues we had earlier. We can appropriate the Vref buffer op-amp.
i'm lost...again ;D. ??? :-\ :-X ??? 8) ;D :)
Quote from: slacker on October 16, 2013, 02:22:38 PM
This setup but with something like my original resistor switching idea should work better because then the gain will go up in bypass.
which setup?...where am i?...arghhhhh....
this?.
http://www.diystompboxes.com/smfforum/index.php?topic=101126.msg939858#msg939858
On my phone so can't post a link. The feedback thing I posted in post number 363 but replace the fet switch with the resistor version I sent you at the start of this crazy adventure. Hope that makes sense.
Sorry to leave you hanging - have a couple of spare minutes now.
This is what I had in mind:
(if you don't want to use the FET swtich, then slacker's 2 x 4k7 resistor divider to ground should work too).
(https://dl.dropboxusercontent.com/u/11996927/another_try_at_Robs_reverb.jpg)
Oh - and nice demo Rob.
cheers guys... 8)
arghhh another opamp.. :icon_eek:
gonna need a bigger boat.. breadboard.. i'll squeeze the bugger on and give it a go.... ;)
nope - look again. I used the op-amp you were using to buffer Vref, which I don't think is mission-critical.
ahhh gotcha..
well....tried it. with strange results.
the overall reverb is not as full as before...
the feedback pot becomes a kind of 'delay time' pot, when turned fully anti, it goes into a tight slapback delay, and borders on oscillation too....but defo not reverb.
the other end of the pot is reverb, but like i say its not as full reverb as before..... :-\
It might be loading the brick down a pinch, so you could try increasing the 220k feedback resistor. You could try 1M feedback resistor and 1M feedback pot, which will also give you unity gain out of the new op-amp.
Not sure why it would be causing a slap-back effect unless there is really weird phase issues. Did you use the optional caps?
just tried that, the oscillation is really bad, its like a boomy bass distortion, nothing like normal reverb decay...totally unusable.
and has cut the fullness of the reverb..
tried optional caps/in out too..
heres a clip...of the range to show you what i mean.. 1M POT fully right ....then 12 o'clock...then fully right.....nasty.
https://dl.dropboxusercontent.com/u/7464107/nastyverb.mp3
Yup - dark and then overdriving the brick.
You probably want a feedback resistor at least 2x the value of the feedback pot to prevent the clipping, so I'm not suprised about the clipping. The 470n cap should be cutting some of the bass from the feedback, but you may need to drop this value quite a bit.
However, with the feedback gain at 0 (ccw I guess) does it sound different than having no feedback loop at all?
Quote from: samhay on October 17, 2013, 11:52:51 AM
However, with the feedback gain at 0 (ccw I guess) does it sound different than having no feedback loop at all?
yeah its not the full lush reverb/decay as we had before...its like its cut it in half (limited)
With the feedback ccw, there should be no feedback, as there should be no output from the new op-amp. Does this sound the same if you then disconect the feedback (e.g. pull a jumper to the new op-amp)?
with feedback ccw i get a little reverb..
if i pull jumper from fb pot 3 to pin 1 it oscillates madly (in that dirty way)
if i pull jumper from fb pot 1+2 to pin 2 i get a quiet fuzz..
Sorry - not sure which op-amp pin 2 belongs to.
I'm trying to determine whether the new op-amp is affecting the feedback-less reverb, so what happens if you remove the connection between the 10k/10k pot junction from the brick and the 100n (if there) or feedback resistor?
If that doesn't change the way the reverb sounds without feedback, then we should be able to tame the frequency response and gain of the feedback op-amp to hit the sweet-spot where the feedback just causes osciallation.
Have we ever tried just sending the feedback back into the input of the brick? Stick a resistor from pin 8 of the opamp to pin 3 of the brick so the opamp isn't connected directly to it then feedback from output of brick through caps and pot into input.
^Have we ever tried just sending the feedback back into the input of the brick?
Nice idea. The 10k input impedance of the brick may load down the reverb pot if we don't split the outputs, but otherwise it should work - it work's in my design anway. ..
ok, i'll try that..in for a penny etc..
so resistor between pin 8 - brick 3.. (value?) ..
then out from the 2x 10k's ...100nf...220k...100kpot...100nf...then goes too ?..
Quote from: deadastronaut on October 17, 2013, 12:55:19 PM
(value?) ..
Dunno, try 10k for starters maybe. May need to diddle with it to find a suitable value, might also need to increase the gain from the opamp to keep input signal at a good level.
Quote
then out from the 2x 10k's ...100nf...220k...100kpot...100nf...then goes too ?..
I'd take it straight from one of the outputs of the brick, probably ditch the 220k for starters or make it something much smaller, we've got no boost in the feedback loop now, out from 100n from the wiper of the pot goes to pin3 of brick.
out of curiosity whats the difference with 5/6 outs?.
righto, i tried that, with varying values , however its cutting the reverb fullness + overall decay length again...arghhh... :)
I think we are forgetting to account for the mojo.
I'm a bit lost as to where you are now - what have you got on the breadboard at the moment?
i went back to this version to get it working normally again, and it had the best feedback with good controllable oscillation.
but still open to ideas.. :)
(https://dl.dropboxusercontent.com/u/7464107/samhaytails.jpg)
OK - interesting to hear that shorting the op-amp gain worked the best.
If you want to try to get more feedback in tails, you could try and short R13 at the same time as you short the op-amp feedback loop. This is fairly large kludge, but might just work ok - in this case, you just need to put a second FET switch parallel to R13 to give it a try. If the feedback is then too loud, a series resistor to the FET might help.
Quote from: chromesphere on June 11, 2013, 07:16:15 PM
Quote from: deadastronaut on June 11, 2013, 06:42:00 PM
cool, wasn't the oscillation done by changing 33k to a 22k?..IIRC.
68k ? :)
^ thats what i did
I used 68k as per the PDF.. could that be why the Osc switch seems to have no effect for me? Should I change the resistor to 22k?
^ yes. 22k.
@sam hold on, that schemo isn't quite what i have i think...
hmm.. I've swapped it, but still not noticing the Osc switch making any difference, and especially not like in Chromesphere's video...
^ drop it to 10k then..should oscilate like a bugger.. :) (btw there is no 68k in my layout.)
which layout/pcb?..
right i went back to the drawing board with this just so i knw where i am and works fine, , i kept the wet/dry/ and kept the fet switch.
(the fet switch when off is letting a little reverb through though..) when on everything is fine and lush reverb again..with great feedback/decay 8)
now lets try and nail this tails bugger... :)
(https://dl.dropboxusercontent.com/u/7464107/STANDARDREVERB1.jpg)
(@realalfino: th 22k ocillates like hell. just confirmed it ok.)
edit: when i switch the tails (led off) it decays pretty well...but still have a lot of reverb. just not as much as when led on.
Quote from: deadastronaut on October 18, 2013, 08:11:16 AM
^ drop it to 10k then..should oscilate like a bugger.. :) (btw there is no 68k in my layout.)
which layout/pcb?..
This one: http://www.diystompboxes.com/smfforum/index.php?topic=101126.msg917324#msg917324
Does a 1M resistor from the FET side of C5 to Vref help kill the reverb in tails mode?
hi sam, been busy...
tried that 1M, still has verb though..
I know there was issues with the tails not working as intended, but did slacker's groundin between 2 x 4.7k resistors idea work any better than the FET switch in terms of killing the dry signal?.
morning.. :)
http://www.diystompboxes.com/smfforum/index.php?topic=101126.msg938234#msg938234
same as this you mean, ..and just take the join of the 2 x 4.7ks to ground.?
yes, BUT you want to put a 1u cap betwen the first op-amp and the first 4k7 resistor and bump up C5 to 1u (or there abouts).
Edit - this won't stop the dry signal in the feedback bleeding into the tails, but it might kill more of leaky reverb in tails.
ok, tried that, :)
when not attched to ground i get full verb..
when attached i get verb stil but not as full..but very much still there..
OK.
Perhaps its time to take a walk over to the other forum and have a look at induction's All Star Reverb. This will do buffered tails bypass, at the expense of a wet-only feedback loop, which you may have to revisit.
hmmmm...bummer. :) , i can never get on the 'other' forum...
cheers though sam.
Deadastronaut asked me to comment on this design. I haven't been following this thread, so I apologise if I am repeating someone, but:
The tails switch in this circuit won't work, because the reverb feedback path is taken from the output of IC2d.
When Q2 is off, the signal simply passes to IC2d, then back through the feedback pot to the Belton, gets delayed, and mixes back with the dry, ad infinitum (unless the feedback pot happens to be set to zero).
What is it you (Deadastronaut?) are trying to acheive at the moment?
(I'm referring to this schem)
https://dl.dropboxusercontent.com/u/7464107/STANDARDREVERB1.jpg (https://dl.dropboxusercontent.com/u/7464107/STANDARDREVERB1.jpg)
thanks for taking a look merlin,
i'm just trying to get reverb 'tails' when bypassed...and dry signal when bypassed, so that i can play over the oscillation/feedback 'tails'..
Hi Merlin - yup, a wet-only feedback has been suggested before.
Rob - this should do most of what you want. You can buffer before and after the brick if you want, but the feedback is the same in my 'Another BTDR Reverb' and works pretty well and you get infinite repeats at max feedback.
You may need to play with a few of the resistors to get the level right.
If you want to see how you can add filtering, take a look at my 'Another BTDR Reverb' thread (http://www.diystompboxes.com/smfforum/index.php?topic=104667.0).
Edit - actually, your 'Bright' switch should just drop-in.
Edit2 - oops - the tails switch is 'upside down'. You want to switch the brick side to Vb in tails to prevent a pop. I will fix this later.
Edit3 - the wet/dry mix is not going to work as drawn, as you will not get unity gain unless it is fully dry. We can fix this with a DPDT...
(https://dl.dropboxusercontent.com/u/11996927/Experimental_Reverb.jpg)
Quote from: deadastronaut on October 21, 2013, 07:54:04 AM
thanks for taking a look merlin,
i'm just trying to get reverb 'tails' when bypassed...and dry signal when bypassed, so that i can play over the oscillation/feedback 'tails'..
You can't have tails AND a wet/dry feeback path. (Unless you make things a bit more complicated- probably an extra opamp needed)
If you want tails, then you have to take the feedback path from the output of the Belton, NOT from the output of the whole circuit.
cheers sam: i'll give that a go. nice one man.
@merlin: so would the fet switch be better if placed on the output of the brick then?..
Quote from: deadastronaut on October 21, 2013, 08:05:54 AM
cheers sam: i'll give that a go. nice one man.
@merlin: so would the fet switch be better if placed on the output of the brick then?..
No the FET is fine. Just move the take-off point of the feedback path (I'm guessing pin-5 or pin-6 of the Belton. I'm not sure what the difference is...)
we tried that before i think..
http://www.diystompboxes.com/smfforum/index.php?topic=101126.msg940338#msg940338
and it cuts short the overall reverb drastically (however tails switch works fine)
in my experiments if the feedback doesn't go via pin 14, the reverb isn't the same at all..
I realised in my cut-and-paste haste that there are a few rather non-optimal aspects of the schem I posted earlier - it will be a lot more predictable with input and ouput buffers to the brick, and I will update it momentarily.
okey dokey... 8)
Just to check. Are you happy with the feedback in this version - http://www.diystompboxes.com/smfforum/index.php?topic=101126.msg940653#msg940653
I ask, as it has wet-only feedback.
wet only?..thats what i have at the mo,
apart from fet switch being from ICB pin 6 etc..
and the wet/dry is fine...though dry isn't dry, but sounds good to me yes. 8)
Schem updated.
I stress that this is untested. It also lacks filtering, so if it works, you will probably want to add a few judicious caps to the wet section.
sorry man, i'm have this on breadboard..
https://dl.dropboxusercontent.com/u/7464107/STANDARDREVERB1.jpg
the other feedback version you linked too that goes to the out of the brick wasn't very good no...
ok, back in a minute...
Schem updated. The only way it will work is if we kill the dry signal to the feedback loop in tails, so we now have a 3PDT doing the switching. I don't know how well this will work or sound, but at least I have designed another another BTDR reverb.
Edit - actually, this is only equivalent when the feedback pot is at max. Othewise, we are feeding relatively too much dry signal back into the feedback. It might sound ok at lower feedback settings, but I will have a think about a better approach.
Edit2 - Now somewhat fixed with a bit of a kludge.
Quote from: deadastronaut on October 21, 2013, 08:18:11 AM
we tried that before i think..
http://www.diystompboxes.com/smfforum/index.php?topic=101126.msg940338#msg940338
and it cuts short the overall reverb drastically
That's because that circuit kills the dry AND the feedback simultaneously (so no tails at all, except for what was left in the Belton when the switch was thrown), because the JFET was in parallel with R6.
But in your current incarnation the JFET is in series with R19, so it won't kill the feedback path, so it should work perfectly. Since you already have it on breadboard, it should be easy just to move the feedback take off point and try it out...
Quote
wet only?..thats what i have at the mo
You currently have wet+dry feedback, not wet only.
Quote from: merlinb on October 21, 2013, 10:30:25 AM
But in your current incarnation the JFET is in series with R19, so it won't kill the feedback path, so it should work perfectly. Since you already have it on breadboard, it should be easy just to move the feedback take off point and try it out...
Pretty sure we tried at some point. I think there is a potential problem with phase cancellation (despite the delay), so taking the wet feedback and feeding it back into the inverting pin of Q3 is not ideal.
Quote from: samhay on October 21, 2013, 10:42:59 AM
Pretty sure we tried at some point. I think there is a potential problem with phase cancellation (despite the delay).
The sounds unlikely to the point of impossible. I suspect you were experiencing some other effect.
EDIT: I found the data sheet, now I see that pins 5 and 6 are stereo outputs. For the stereo to serve any purpose they must be different in some way, so the phases from the two outputs must be different to some extent. You could experiment by taking the feedback either from pin 5 or pin 6.
Looking back at some of the comments, I think some of the difficulties encountered in this thread may be due to undiscovered construction errors, rather than design errors.
Quote from: merlinb on October 21, 2013, 10:54:48 AM
Quote from: samhay on October 21, 2013, 10:42:59 AM
Pretty sure we tried at some point. I think there is a potential problem with phase cancellation (despite the delay).
The sounds unlikely to the point of impossible. There are so many delays inside the Belton that any sort of consistent phase cancellation is a highly dubious problem. I suspect you were experiencing some other effect.
I have to admit that I was a more than a little confused/surprised at the time.
It would make sense if there was dry signal in the feedback loop. It is certainly worth revisiting.
morning, where were we?.. :)
the way i see it is the only problem with my breadboarded version is the fet switch not actually cutting off all the reverb in bypass...
ive tinkered with it to no avail..
clip.
reverb...then bypassed..
https://dl.dropboxusercontent.com/u/7464107/reverbfet.mp3
when the feedback is set to minimum, do you still get reverb in bypass?
Quote from: samhay on October 22, 2013, 04:57:57 AM
when the feedback is set to minimum, do you still get reverb in bypass?
no, not a hint.
Just to be double sure, if you set feedback to near maximum and wet/dry to fully wet, do you get any reverb in bypass?
if i set feedback to max, and fully wet i get no sound at all in bypass
full wet reverb when on.
OK, so what you are hearing in bypass is the dry signal at the output being fed via the feeback loop to the op-amp buffer/mixer in front of the brick.
While this might give you the best sounding feedback, it is just not going to work for a tails bypass.
The schem I posted yesterday lifts the dry signal from the feedback in bypass. This will cure this particulalry problem, but will quite possibly make the feedback sound very different in bypass, and mostly negate the point of having tails.
How badly do you want tails?
Quote from: samhay on October 22, 2013, 05:20:06 AM
How badly do you want tails?
hmmmm...i see. :icon_sad:
would be a really nice option though.. :)
Quote from: therealfindo on October 18, 2013, 10:25:25 AM
Quote from: deadastronaut on October 18, 2013, 08:11:16 AM
^ drop it to 10k then..should oscilate like a bugger.. :) (btw there is no 68k in my layout.)
which layout/pcb?..
This one: http://www.diystompboxes.com/smfforum/index.php?topic=101126.msg917324#msg917324
*cough*
Any ideas why I'm not getting the oscillations? :)
^ looking at R O trees schematic version it should be fine... the 33k swapped to 22k should osc like hell.
is your feedback pot ok?....is it doing anything?.
as a blatant kludgey bodgey type solution i just tried this ultra stupidly simple (like me) approach......bear with me on this.. ;)
input...middle lug dpdt...
one throw to reverb in..
other straight to out.
use the other side of dpdt for leds red/green..
true bypassed, with tails...it works. :)
any forseeable problems?..
well it works...33k then 22k osc..
https://dl.dropboxusercontent.com/u/7464107/tailsdpdt.mp3
only thing is when turning volume down on guitar it turns down reverb tails too...thought it was too simple.. ::)
anyhow..
valoosj came up with an interesting idea..
Dear Rob
At the risk of sounding stupid (lack of electronics knowledge ): wouldn't it be possible to add a mixer to your reverb?
When reverb is not desired but tails are, send the input signal straight to mixer input A and the tails to mixer input B. When switching the reverb on, grounding mixer input A and sending your dry signal in the reverb and then to mixer input B.
And if you don't want tails, cut the sound going to B when turning off the reverb.
To my untrained mind, this seems logical. Though, if it were a good idea I'm sure you or Samhay or Merlin would have proposed this.
I hope you get it sorted out because the reverb sounds killer.
Cheers
Yorick
thanks yorick: ;)
I'm not sure if I quite understood correctly, but I think Yorick is suggesting something similar to my suggestion - lift the dry signal to the feedback loop/reverb in tails mode.
Rob - your idea of leaving the output always connected is not a new idea. It can work, but you have a voltage divider between the guitar pickup, the feedback loop and whatever the effect is plugged into. I guess this can get a little unpredictable.
Quote from: deadastronaut on October 22, 2013, 06:04:13 AM
^ looking at R O trees schematic version it should be fine... the 33k swapped to 22k should osc like hell.
is your feedback pot ok?....is it doing anything?.
Yep, the feedback pot is working.
I swapped the 68k in the pcb with the 22k..
oh, wait, just a thought... perhaps I've wired the spst switch backwards..
Quote from: samhay on October 22, 2013, 06:57:48 AM
I'm not sure if I quite understood correctly, but I think Yorick is suggesting something similar to my suggestion - lift the dry signal to the feedback loop/reverb in tails mode.
Rob - your idea of leaving the output always connected is not a new idea. It can work, but you have a voltage divider between the guitar pickup, the feedback loop and whatever the effect is plugged into. I guess this can get a little unpredictable.
yeah thought it was too simple... :)..
@yorick: have you a schemo of what your idea is?....i'm a little confused now too.
Quote from: therealfindo on October 22, 2013, 07:08:52 AM
I swapped the 68k in the pcb with the 22k..
oh, wait, just a thought... perhaps I've wired the spst switch backwards..
The TO Tiree schematic switches a 68k resistor parallel with a 33k resistor. 68k || 33k is about 22k. Using this layout, if you replace the 68k resistor, you will end up with a 13k equivalent resitor in the feedback and it will probably go nuts.
As I see it, you have 2 options, once it is wired up correctly:
1. put the 68k resistor back in
2. remove the switch and 68k resistor and replace the 33k resistor with a 22k resistor.
Quote from: samhay on October 22, 2013, 06:57:48 AM
I'm not sure if I quite understood correctly, but I think Yorick is suggesting something similar to my suggestion -
In order to visualise what I meant:
(https://dl.dropboxusercontent.com/u/155894717/reverb.jpg)
Yorick's idea makes perfect sense, it's what my earlier suggestion to "bypass the whole thing" amounts to.
This solves all your issues, you can have your wet/dry mix and feedback with dry setup. It just seems like admitting defeat to me, as we should be able to make it work without resorting to that.
Here's a schemo that basically does what you need.
http://www.diystompboxes.com/smfforum/index.php?topic=92036.0 (http://www.diystompboxes.com/smfforum/index.php?topic=92036.0)
You've already got the first buffer so you don't need that. This won't give you the option of true bypass, you'd need to use electronic switching in place of the switch if you still want that.
Am I missing something, or is there is no feedback in Yorick's schematic?
^ no idea.. ???
so how do we incorporate both schemo's.. :)
(https://dl.dropboxusercontent.com/u/7464107/tailsloop.jpg)
(https://dl.dropboxusercontent.com/u/7464107/STANDARDREVERB1.jpg)
^so how do we incorporate both schemo's
In the simplest sense, you plug the brick's input into Send and its output into Return.
cool, i'll rig up the little schemo on a seperate breadboard and give it a whirl.. 8)
To test it does what you want chuck the whole of your schemo minus the electronic switching in the send/return loop. If it does the job we can refine it.
^ yep thats what i was going to try, just to test. cheers guys. :icon_cool:
wish me luck... ;D
edit: ...my brick came loose.. ::)
YAY!!!...IT WORKS!!!..WHOOOOHOOOOO.....
https://dl.dropboxusercontent.com/u/7464107/DOOBYDOO.mp3
^22K.
Nicely celebrated.
Have you thought about how you are going to tidy it up now?
nope... :)
but i'll be glad to get this bugger in a pcb layout and off my breadboard/s at long last.. :)
Yaaahhhhhhhhhh ;D sounds great.
I think the main thing to sort out is do you still want the option of tails or true bypass or are you happy with tails/no tails buffered bypass, same as the Echo Base. The looper schematic can easily be tweaked to offer no tails with a toggle to select whether it kills the send or the return. If you want the true bypass option then we'll need to replace the switch with fets or something.
The other thing is are you bothered that it inverts your dry signal?
If you're not, then if you ditch the opamp that's generating vb we can use that as the output mixer and use your existing input buffer in place of the one on the looper. If you want the dry output in phase with the input then we need to add another opamp or possibly we could make the output mixer non-inverting.
Great :)
And does this have any possible negative consequences?
Quote from: slacker on October 22, 2013, 02:17:41 PM
The other thing is are you bothered that it inverts your dry signal?
Quote from: slacker on October 22, 2013, 02:17:41 PM
Yaaahhhhhhhhhh ;D sounds great.
I think the main thing to sort out is do you still want the option of tails or true bypass or are you happy with tails/no tails buffered bypass, same as the Echo Base. The looper schematic can easily be tweaked to offer no tails with a toggle to select whether it kills the send or the return. If you want the true bypass option then we'll need to replace the switch with fets or something. tails and true bypass would be cool
The other thing is are you bothered that it inverts your dry signal? hmmmm...i guess
If you're not, then if you ditch the opamp that's generating vb we can use that as the output mixer and use your existing input buffer in place of the one on the looper. If you want the dry output in phase with the input then we need to add another opamp or possibly we could make the output mixer non-inverting. sounds good to me
nice one ian. 8) 8) 8)
Quote from: Valoosj on October 22, 2013, 05:14:02 PM
Great :)
And does this have any possible negative consequences?
recording maybe?.. (phase inverting) cancelling....just thinking aloud.
if we can get this loopy bit drawn up, i'll test it out.. :)
Quote from: deadastronaut on October 22, 2013, 01:15:03 PM
nope... :)
but i'll be glad to get this bugger in a pcb layout and off my breadboard/s at long last.. :)
Can't wait! All of this stuff lately has been WAY over my head. I'm ready to built it again (this time a working one :D)
just to keep things in context,
here is what is on the breadboard at the mo..
(https://dl.dropboxusercontent.com/u/7464107/reverbwithlooper1.jpg)
something like this?
Note that cap after R12. Not sure where you want to put the volume pot (if at all).
(https://dl.dropboxusercontent.com/u/11996927/reverbwithlooper1.jpg)
cheers sam. nice one, what value cap after R12?.
i definately want a volume so i can adjust it when fully wet etc..
vol probably best on overall out after C17, and lose the R20?.. . ..its got plenty of vol as it is when compared to breaboard 3pdt TB
Good job,been following this closely. Am I right in thinking we're basically just taking the original schematic and plonking the ins and outs into the switching scheme?I'm on my phone so can't compare easily with the original schematic I used.
If this is the case,i might just do an optional daughter board tails vero in conjunction with the one I drew up before (which is still unverified)
Quote from: deadastronaut on October 23, 2013, 10:50:34 AM
cheers sam. nice one, what value cap after R12?.
i definately want a volume so i can adjust it when fully wet etc..
vol probably best on overall out after C17, and lose the R20?.. . ..its got plenty of vol as it is when compared to breaboard 3pdt TB
Don't know about the value of the new cap - how big is your wet/dry pot? Either way, I would start with 1u and then tweak to taste.
As it stands, slacker's loop circuit is unity gain for both the loop and bypass. If you want a volume control on the end of it, then I would replace R18 (in his schem) with a 100k pot.
Quote from: samhay on October 23, 2013, 11:28:47 AM
Quote from: deadastronaut on October 23, 2013, 10:50:34 AM
cheers sam. nice one, what value cap after R12?.
i definately want a volume so i can adjust it when fully wet etc..
vol probably best on overall out after C17, and lose the R20?.. . ..its got plenty of vol as it is when compared to breaboard 3pdt TB
Don't know about the value of the new cap - how big is your wet/dry pot? Either way, I would start with 1u and then tweak to taste.
As it stands, slacker's loop circuit is unity gain for both the loop and bypass. If you want a volume control on the end of it, then I would replace R18 (in his schem) with a 100k pot.
wet/dry is 10k.. i'll experiment with that cap then.
100k pot on pins 6/7 it is then......like this.?
i'm guessing we can do away with IC1a Vb now too then..?..if so we can just use a quad.
(https://dl.dropboxusercontent.com/u/7464107/reverbsammods1.jpg)
@mmlee: i guess so..
^wet/dry is 10k.. i'll experiment with that cap then.
1u would be a good start, but you may want a bit more if you a playing a bass through it.
^100k pot on pins 6/7 it is then......like this.?
Nope - lift the ground connection and swap the pot lugs - e.g. 1&2 to the inverting input and out, respectively. If that doesn't make sense, then a conventional volume pot on the output will work fine too.
^i'm guessing we can do away with IC1a Vb now too then..?..if so we can just use a quad.
Yes, sorry I mean to mention this earlier.
One more bit to tidy up - we have 2 separate Vref networks at the moment, which I would consolidate into one.
Looks good chaps. I think the volume control is probably better off where it was on the original schematic, after IC2d that way it will only control the level of the effect, sticking it on the end will also affect the bypassed volume.
^ good catch.
so pin 14...vol pot (3+2 joined) then 1....100n.....etc..
shall i still keep the 100k across pins 6/7 then?. ( IC3b)
I'd do the volume pot and mixer the same as you have them here, "Out" hardwired to "Verb out".
(https://dl.dropboxusercontent.com/u/7464107/reverbwithlooper1.jpg)
d'astro, what are the tapers of the pots? And could you tell me what the PGROUND is? I saw it near the reverb brick as well in one of the previous schematics but not anymore.
Also, could you use a 78l05? Or does the reverb draw too much current?
@ian. Righto, ill rejig the schemo, then test it out. 8)
@yorick, im using trimmers on bread, but i guess all lin apart from vol.
i have both those grounds to the same ground on breadboard, so no problemo.
also using 78L05..reg.
What software is that schematic drawn with?
Can't wait until you verify the schematic :) I always thought I'd never again have a reverb on my pedalboard. Now I'm coming back from that statement ...
so is there a pcb layout for the newest version of this? I found a couple older links for layouts that did not work. I can not figure out how to search this site! sorry! any help would be greatly appreciated
okay, i found the artwork on page 10, is that the most recent art and schematic?
^ no, ...its not finished as yet...still on breadboard....but soon...ish.
@bugg: its circuit wizard ( a mate gave it to me ages ago and i find it really useful for doing quick schemos) the pcb side of it is rubbish btw, it has an auto route function
which looks great, but it makes more jumpers than sheep... ::)
@yorick:
got crap to do today, but should be able to verify a bit later... ;)
i really dug chromesphere's demo with the board he used. where is the most recent, verified artwork and layout?
^ read above reply...
You can also get rid of R11 and R12, as they don't appear to do anything useful.
In fact, the whole schematic is a mess right now, and I suspect at least one of those opamps isn't required. It would help if deadastronaut listed exactly what controls and features he wants from this thing...
sorry for the mess, but its been through a lot of adjusting...you should see my breadbords ;D ;) anyway..here is what i have working on breadboard at the mo.
i moved the vol to the end, as its just better level wise..compared to straight out of the opamp. (pin 14)
got rid of vb opamp..
here are the requirements (which are all working as planned so far)
true bypass and optional tails.
vol
level
mix
damp
decay
hi /lo
oscillation on/off
(https://dl.dropboxusercontent.com/u/7464107/REVERBTAILSNEWEST1.jpg)
you can lose:
- R13, R17, C16 (slacker's Vb network) and connect their intersection to Vb.
- R20 (output resistor in parallel to vol pot)
- one of the output caps (1u or 100n) from IC2d
you can connect the wet/dry pot to ground rather than Vb. Actually, as Merlin suggested, the resitors/cap after this pot could do with tidying up.
cheers sam...i'll do those adjustments now..
here we are..
(https://dl.dropboxusercontent.com/u/7464107/REVERBTAILSNEWEST2.jpg)
If it doesn't work as planned, you may need to put a resistor back where R11 (33k) was (I would use 100k or 1M), to bias up IC2d.
It should be ok, as it is biasing from the reverb pot, but this thing hasn't always behaved as expected.
What is SW2 for? It appears to be a bypass, but I thought this was supposed to be a true bypass pedal?
Also, you can't have tails and true bypass, so I'm not sure what your intension is here...
A better way to do the volume control would be to use a pot for R3. That way it doesn't rape your output impedance.
IC2d needs a resistor from the non-inverting input to Vb. Actually it was better before, where the wet/dry pot was returned to Vb. Not sure why you changed that, because now it will make scratchy sounds..
vol
level What's the difference between vol and level?
mix
damp
decay Is this the same as feedback?
hi /lo Is this for bass cut? Or treble cut, or what?
oscillation on/off
Do you care if the pedal is inverting or not?
switch 2 allows tails,
and i have a true bypass breadboard. (which eventually will be a pedal 3pdt
so i do have both. and is working as such.
the tails : tails off so i can play clean over the reverb dying off .
the true bypass : acts as a non tails (cuts off instantly) mode.
EDIT:
better?..
(https://dl.dropboxusercontent.com/u/7464107/REVERB666.jpg)
vol ..is for overall volume..
level is the amount of reverb
decay=feedback.
hi/lo= hi, a little brighter for my acoustic , / lo=normal.
yes i do care that its inverting.. :) , ian mentioned that earlier..
clip of TB and tails..
https://dl.dropboxusercontent.com/u/7464107/TB%20and%20tails.mp3
tb first, then tails/bypass..
(https://dl.dropboxusercontent.com/u/7464107/REVERB666.jpg)
Quote from: merlinb on October 25, 2013, 10:43:58 AM
Also, you can't have tails and true bypass, so I'm not sure what your intension is here...
IC2d needs a resistor from the non-inverting input to Vb. Actually it was better before, where the wet/dry pot was returned to Vb. Not sure why you changed that, because now it will make scratchy sounds..
I think the overal goal is to have a switchable tails option - stomp switch selects on/off and tails toggle switch selects true bypass or tails. This is quite do-able in the current schem with a 3PDT footswitch, but may make having an indicator LED a bit more challenging.
I think there is a case of too many cooks at the moment - The wet/dry pot is AC coupled and will be pulled to ground when the bypass switch is engaged. That's why I suggested it be tied to ground.
Quote from: deadastronaut on October 25, 2013, 11:02:30 AM
vol ..is for overall volume..
level is the amount of reverb
If you did the mix control differently then you could get rid of the 'level' control. You would just turn the mix to 100% wet (if that's what you wanted) and then adjust the volume to suit.
Quote
yes i do care that its inverting.. :) , ian mentioned that earlier..
Ok, but the circuit you have now is inverting...
Quote from: samhay on October 25, 2013, 11:10:19 AM
I think the overal goal is to have a switchable tails option - stomp switch selects on/off and tails toggle switch selects true bypass or tails.
If you have a true bypass option, why would you want the tails to be switchable too? ??? Surely the only two options you need are:
1: True bypass
2: Not true bypass (i.e. tails).
What is the point of having the third option "not true bypass and no tails"?
Quote
I think there is a case of too many cooks at the moment - The wet/dry pot is AC coupled and will be pulled to ground when the bypass switch is engaged. That's why I suggested it be tied to ground.
Yes, the pot should go to ground as it is. Only R11 is needed.
Or get rid of R11, move C20 to between R24 and R19, and return the pot to Vb.
You want to have 1 of 3 options:
True bypass
Buffered bypass with tails
On
The toggle switch selects between true and tail bypass, the stomp between on and bypass.
schemo above updated...
clip of TB, then tails/bypass..
https://dl.dropboxusercontent.com/u/7464107/TB%20and%20tails.mp3
Quote from: samhay on October 25, 2013, 11:19:59 AM
You want to have 1 of 3 options:
True bypass
Buffered bypass with tails
On
The toggle switch selects between true and tail bypass, the stomp between on and bypass.
OK I get that (I didn't consider "on" to be an option :icon_lol:). But I don't see how the current schematic acheives it. The footswitch (which is part of another unit and not on this schematic, right?) is always true bypass, or on. What am I missing?
Something like this maybe: http://www.diystompboxes.com/smfforum/index.php?topic=101126.msg938146#msg938146
But with the middle lug of the 3rd row of the footswitch going to ground and the top and bottom lugs to the two resitor dividers in the bottom of Rob's schem.
Not much room for an LED left though.
Rob did you have other ideas?
leds: i was pondering that i could use half a dpdt for the tails switching, and other half for leds. red on/green off. :icon_idea:
and make that dpdt footswitch too. 8)
and have a 3pdt with led as per normal tb. as i have it now.
like this:
(https://dl.dropboxusercontent.com/u/7464107/dpdtleds.jpg)
?..how do we make this schemo non inverting then?...and what will be the advantage of doing so?
I think you'll need to use the 2nd half of the tails switch to "bypass" the 3PDT when the pedal is off in tails mode, correct?
Since tails mode overrides the truebypass nature of the 3PDT, you'll want the Tails switch to maintain a connection between the output of the PCB -> output jack.
Otherwise true-bypass is going to kill your tails.
..
okey dokey..cheers bugg.
how do we make this schemo non inverting then?...
and what will be the advantage of doing so?
Rob - you could also look at a bi-colour LED for your switch ,
http://spiratronics.com/optoelectronics/leds/multi-colour-leds/bi-colour-3mm-leds.html
cheers mark, yeah i have some of those.. 8)
well, seeing as its going to be a stormy day here..
i thought i'd get on this again...even though your all probably sick of it/me, and my dumbass ?'s...and i don't blame you ::)
but when its eventually sorted, i reckon it'll be on your board for a very long time...i know mine will. thats why i'm persevering with it.
so...will just swapping the inputs to + like this make this a non inverting effect?..or is there more to it?..will this be ok?
(https://dl.dropboxusercontent.com/u/7464107/reverbb666noninvert1.jpg)
You need to swap the inputs of IC3b. The overall volume now won't work, so you will need to move this to after the output cap.
R23 and R25 are obsolete. Not sure how well the switching will work - you may need to up R21, but this will then affect the gain of the dry signal into IC2c and also the wet/dry pot, so you may have to do quite a bit of tweaking.
Cheers sam, so like this...and tweak R21.
(https://dl.dropboxusercontent.com/u/7464107/reverb666noninverting1.jpg)
Quote from: deadastronaut on October 27, 2013, 07:52:26 AM
so...will just swapping the inputs to + like this make this a non inverting effect?..or is there more to it?..will this be ok?
No that won't work, assuming you mean IC2c, the effected signal is fine it's the dry and bypass signals that get inverted. The bypass signal goes through IC3a non inverting then IC3b inverting do comes out inverted. The dry signal goes through IC3a and IC2d both non inverting then through IC3b inverting so comes out inverted.
The easiest way to fix it is to make IC3a into an inverting buffer, then the signals get inverted twice so come out non inverted, so + input to VB signal in through a cap and then a 1 Meg resistor into the - input and a 1Meg resistor from out to - input. Same as the input buffer here http://www.aronnelson.com/gallery/main.php/v/slackers-stuff/album170/echobase.png.html (http://www.aronnelson.com/gallery/main.php/v/slackers-stuff/album170/echobase.png.html).
This can be noisy though due to the high resistor values needed to keep the impedance high so instead you could chuck a fet buffer in front of it, to provide a high input impedance and then use smaller resistor values in place of the 1 Megs.
EDIT: started writing this before the last two replies.
I was just going to chip in with slacker's idea of making the input buffer inverting. If this is not going to be at the front of your pedal chain, then you could get away with a moderate input impedance to keep the noise down.
As far as the current schem goes:
You need to make IC3b into a buffer like 1C3a (it's a comparator at the moment), so short the (-) input to the output, remove the Vb connection to the (-) input, and bias up the (+) input with e.g. a 1M to Vb.
Sorry, I meant to remove R24, not R25 (which I think will help, but may want to be the same value as R22).
If it works, then great, but if not, it might be a bit of a faff to get it to play nice.
Do you really care if the effect is inverting?
''Do you really care if the effect is inverting?''
not particularly, but ian and merlin mentioned it earlier..so i presume this may be a bad thing.
what would be the benefit/possible pitfalls of it being inverting, compared to non-inverting then?.
is it a phase invert issue?..(recording etc)
anyway...does this look ok now?.
(https://dl.dropboxusercontent.com/u/7464107/reverbnoninverting6661.jpg)
The bottom of R10 goes to Vb and the (-) input of IC3b should not be connect to R10 or Vb.
ok, i just stripped off my breadboard and started again to tidy things up a little.. :)
i now have this...but no reverb at all...is this ok....i'll double check everything in a mo.
R13 ok? vb at pin 9 0k?.
edit: just checked, sound but no reverb at all.. ???
(https://dl.dropboxusercontent.com/u/7464107/reverb888.jpg)
You need to switch pins 9 and 10 IC2c.
cheers ian,. done that, still no verb..
how is pin 12/13?.
Sorry missed those before, yeah they need flipping as well.
am i losing it or am i back to were i was before i tried '' non inverting'' ?
arghhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh my head... :)
just to clarify i was trying out 'non inverted' ...even though i have no idea what effect or trouble that ''inverted' may cause if any....
the window is looking very promising.. :icon_twisted:
No the crucial bit is IC3b, that is now non inverting, so bypass/dry is now not inverted.
ahhh i see...cheers man. 8)
righto, so this should work ok then?..
just asking as i'm not getting verb...but i'll check my breadboard over again..(hows that sw2)
(https://dl.dropboxusercontent.com/u/7464107/REVERBNONINVERTED1.jpg)
Looks fine to me, I think you want a cap before the wet/dry or connect the pot to VB instead of ground, don't think that would stop it working though. I'd get it working at the output of ic2d just in case it is the output stage that's causing problems.
On the inverting question, if you only use tails bypass then in a "normal" signal chain git >> pedals in series >> amp then there's not really an issue. The signal will always be inverted, but there aren't many scenarios where that matters.
If you use true bypass though then in bypass the signal is not inverted and when you engage the effect it inverts, this might cause some problems, I can't think of any off any top of my head though.
It's really only a problem if you start mixing signals in parallel then you can get cancellations if the signals are out of phase.
I think it's generally just good practice to keep the dry signal "in phase".
Before anyone starts on me, Yeah I know the Echo Base is inverted :D
right i have it working...sort of.. (as above schemo)
but its no where near as full and as much feedback/decay as before...with C20 at 1uf, i get hardly any verb at all...dropped that to 100nf, but still moody..
and feedback/decay is cut short.....even when i change 33k to 22k...which oscillated like hell before...and feedback pot hardly does anything.
when i have wet dry pot to ground...with 100nf instead of 1uf wet dry works.
but if i put that wet/dry pot to vb, the switch pops like f... :icon_eek:
also bypassed (sw2) is way louder than when verb on.
so still a few niggles.. :)
Increase R6 for more wet volume.
You don't want the wet/dry pot to Vb. You may want this pot to be 100k though.
morning...been blown away yet...was a nasty storm down here..
changed R6 to 47k..bit better..if i put it up to 100k it blows the ass out of it (mass distorts)
something defo not right with the feedback though, its gone like the problem we had with some of those earlier mods...really cuts off quick.
hardly any decay at all really.
Got a bit damp this morning, but I seem to have been far enough north to miss most of the wind. Hope you are keeping out of the worst of it.
Perhaps try increasing R9 instead of R6 - this will bump up the gain after the brick, rather than before it.
Does the feedback still cause oscillation when the effect is on?
If so, the feedback loop is ok, but the bypass switching needs more work - perhaps try removing (or lowering) R3?
''Does the feedback still cause oscillation when the effect is on?''
no not at all...dies off very quick,
i can adjust R3 to a higher value whichgives a louder output, but at the cost of the reverb being quieter..
what happens if you set R3 to be e.g. 47k?
just makes overall level a bit louder..
Is the overall level the bypass level, the level of the effect, or both?
Quote from: samhay on October 28, 2013, 09:35:02 AM
Is the overall level the bypass level, the level of the effect, or both?
both.
ok. I think this is the time when we start to appreciate why mixers usually use inverting op-amps.
yeah i think so, its not a patch on when it was inverted.. :( mad eh!..
(+) inputs are (very) high impedance.
(-) inputs are very low impedance.
It makes a difference.
just a mad idea..
put it back to where it worked really well, with the loop etc.. (which it looks like i'll have to anyway)
and whack a phase invert switch on the out?..
Or just make the input op-amp inverting
erm.....so would the out be non invert then..?
edit:
oh, sod it, think i'll just go with the inverted + loop as that was the most promising result with plenty of decay, and good levels and nicely tailed...with on/bypassed too, sounded lovely...
besides, if inverted is good enough for ian's excellent echo base its good enough for me too.
i'll re- breadboard it that way, and go from that standpoint...... :)
Quote from: deadastronaut on October 28, 2013, 12:55:32 PM
erm.....so would the out be non invert then..?
No, input and output both inverted, so dry signal gets inverted then get re-invereted by the output so it come out the right way up, like maths a minus times a minus equals a plus.
Or like you said just sod it and let people who want to do fancy pants parallel effecting take care of any issues them selves ;D
The schematic is fine- it has clearly been constructed incorrectly. Endless modification are a waste of time until you fix the wiring errors on your breadboard. Keep calm, and don't be hasty about it. You will be surprised how many you find.
@ian, right, ok, so....now i'm really lost.. :P
@merlin: hi, yep i know what you mean, i have had the odd face palmy moments with this , however, believe me ive checked the last schemo/breadboard over and over...node by node with a pen and printout.
the various experiments and ideas we have tried other than the 'inverted+loop schemo' have had a drastic effect on the brick reverb feedback/decay and behaves quite unusable, to me anyway...
(unusable meaning no point in tails at all really when the decay/feedback dies off to quick etc). ...it just becomes a very different, and too subtle effect compared ...
Quote from: deadastronaut on October 28, 2013, 03:36:23 PM
@ian, right, ok, so....now i'm really lost.. :P
See my post number 537 from the other day.
ok, cheers man, i must 've missed that..
so similar to this then?.
(https://dl.dropboxusercontent.com/u/7464107/SLACKERSNONVERT1.jpg)
Quote from: deadastronaut on October 28, 2013, 04:44:22 PM
believe me ive checked the last schemo/breadboard over and over...node by node with a pen and printout.
And yet, errors remain. It happens to all of us. Check again. And again.
Quoteso similar to this then?.
Yuk. Build that if you want a white noise machine.
Suggestion: (Bright switch could be implemented around IC2. Heck, since this version eliminates one pot, you could have a tone pot instead)
(http://i81.photobucket.com/albums/j207/merlinblencowe/666reverb_zpsd284a583.jpg)
well that looks different.. :icon_cool:
cheers merlin, i'll give that a go on breadboard ( and i will make sure i triple check ok. ;)
thanks man Rob.
edit:
ok, i have merlins working on breadboard, and it works, yay!..but there are some issues , here are my findings.
: completely bypassed (breadboard 3pdt off ) = true bypassed normal level . ( 3pdt pops like hell even with 2.2M pulldown added though) where it was absolutely silent before)
: breadboard 3pdt on, with circuit sw2 in bypass = vol halved, (vol pot will not adjust level)
:breadboard 3pdt on, sw2 reverb on = dry/wet acts as a reverb level , CCW is dry however, when dry that vol level is still half of TB. ( vol pot will not adjust level)
and when sw2 is switched to turn reverb on, but still dry, the level is higher than sw2 in bypass.
:when dry/wet is turned CW it is fully wet, but much quieter than dry ( vol control works on this but even at max its still quieter)
: feedback/decay is great...it even oscillates with just the 33k....but only when near or fully wet, it will not oscillate halfway etc..
:damp=fine..
:)
How does it work without the 3PDT?
BTW, do you need a bypass switch for a reverb? What happens if you omit the switch and just turn the mix or feedback pot CCW to eliminate the reverb? I'm doing this on the Solstice and it works great.
Quote from: deadastronaut on October 28, 2013, 07:29:28 PM: completely bypassed (breadboard 3pdt off ) = true bypassed normal level . ( 3pdt pops like hell even with 2.2M pulldown added though) where it was absolutely silent before)
No reason it should pop any more than what you had before.
Quote: breadboard 3pdt on, with circuit sw2 in bypass = vol halved, (vol pot will not adjust level)
The volume in bypass should be the same as true bypassed. If it's not you've either done something wrong or there's some flaw in Merlin's plan that I'm not seeing.
Volume pot will not adjust bypass level it only contols the effected signal.
The fact you say the volume doesn't affect the level of the effected signal in some cases sounds like a wiring error the volume pot should be able to turn the effected volume completely off in any setting of the other controls.
Quote from: deadastronaut on October 28, 2013, 07:29:28 PM
( 3pdt pops like hell even with 2.2M pulldown added though) where it was absolutely silent before)
Have you included pull-down resistors at the input and output?
Merlin's suggestion is quite similar in topology to my design. Personally, I like the idea of a single mix pot rather than separate wet/dry and reverb pots too.
Comments:
Merlin's design is inverting too.
In bypass (sw 2 'down') the volume pot should not do anything. If you want it to, then move it back to the output.
Try taking the feedback loop from the output of the IC2c output cap (10u) rather than after the mix pot. This way, you will probably get more usable feedback/oscillation when the mix is relatively dry.
@john: switch is for tails and boss style...
@merlin, i have a 2.2M on in, 1M on out now, better, but still a little pop......however the sw2 pops like hell.
@ian: i'll check it over,
@sam: so were still inverted then?.
the reason i want a ''reverb level'' pot is that on certain settings, e.g. fully wet i want to be able to boost that a little to bring it up to bypass levels. (i do a lot of ambient music)
as certain settings can make it 'seem' a lot lower in vol...(as you'll hear in the clip)
here s a clip of what i have now..one take.
clip order: true bypass/ then TB on sw2 off/ then sw2 on with wet fully CCW...Then turning wet/dry CW.../ then back to SW2 off / then true bypass again..
https://dl.dropboxusercontent.com/u/7464107/merlreverbtest1.mp3
i'll check this over in the cold light of day...make sure i have it right first, and redraw it so i can tweak.
Quote from: deadastronaut on October 29, 2013, 08:13:10 AM
however the sw2 pops like hell.
Measure the voltage on all the poles of the switch- they should be zero. If not then you have a cap missing, or something miswired.
Quote
the reason i want a ''reverb level'' pot is that on certain settings, e.g. fully wet i want to be able to boost that a little to bring it up to bypass levels.
You can acheive the same result by turning the mix control to 100% wet, then turning up the volume pot to give the desired boost (if it doesn't have enough boost then you just need to reduce the resistor connected to its wiper a bit, to increase the available gain).
cheers merlin, yeah i have 0.28 on one of the poles..so something is up..
ive redrawn your schemo, so i can tinker...
i'll go over this node by node with printout paper n pen, oldschool style ;)
(https://dl.dropboxusercontent.com/u/7464107/MERLINSREVERB1.jpg)
@sam: so were still inverted then?.
yes - IC3a in non-inverting and IC3b is inverting.
Does it bother me.
no
@sam : not bothered either.. ;)
righto..
re breadboarded , node by node checked off on printout....all working yay!.
sw2 still pops though, i'm getting 0.35v on right side on R22, which i swapped to 47k,
which now means the levels of TB and fully CCW Dry and also sw2 bypass are much better vol unity yay!......and stil have plenty of vol adjustment for reverb when fully wet too...yay again! 8)
so were getting there, but sw2 still pops.. :)
btw thanks merlin, its a much tidier and smaller footprint than i could have come up with..very cool. :)...even smaller than my original, sounds great 8)
Quote from: samhay on October 29, 2013, 05:49:22 AM
Comments:
Try taking the feedback loop from the output of the IC2d (<edited for new schemo) output cap (10u) rather than after the mix pot. This way, you will probably get more usable feedback/oscillation when the mix is relatively dry.
i'll try that, thanks sam.. 8)
could sw2 be swapped for the fet switch?.
Quote from: deadastronaut on October 29, 2013, 11:08:47 AM
i'm getting 0.35v on right side on R22, which i swapped to 47k,
Dinfinitely something not right. You sure you haven't got the inputs of one of the opamps accidentally swapped?
A leaky cap could also cause the DC on the switch, but I still suspect a wiring error.
checked all opamp connections fine..
from pin 1=4.57v
into 10uf > negative side =0.07v
47k (R22) right side 0.00
1k (R21) right side 0.07v
right side of R12 =0.26v
right side of R19 =0.07
i'll swap my jumpers...they might be suspect. :)
it changes with sw2 position..
reverb on 0.07
middle 0.27
bypass 0.01
(haven't got a spdt at the mo , using half a dpdt)
>
@john: switch is for tails and boss style...
Quote from: samhay on October 29, 2013, 05:49:22 AM
Comments:
Try taking the feedback loop from the output of the IC2d (<edited for new schemo) output cap (10u) rather than after the mix pot. This way, you will probably get more usable feedback/oscillation when the mix is relatively dry.
sam, just messed with this...but not sure if i had it right, ...do you mean move the connection that goes from feedback pot 3 to the mix pot 2 , to the - 10uf?.. if so what happens to mix pot 2 ?.
the way i tried it was just wet with mass oscillation..
note: as per schemo i'm getting oscillation when fully wet only...thats why i thought i'd try this.
:still getting pop.. :)..tried a fet switch, but still lets verb through.
After the 10u output cap, split the signal so that it goes to both the mix pot and the feedback pot.
Mix pot 2 would now only go to the volume pot.
Realised last night that you can do an indicator LED with a Millenium bypass, so there should be no need for a FETswitch. Your pop is still a worry though.
aha, thats better,
much better control over the feedback.. 8)
however were back to that old chestnut of tails dying off too quickly in sw2 bypass :)
and dry is not fully dry now..when fully CCW
^much better control over the feedback..
That's what I was expecting
^however were back to that old chestnut of tails dying off too quickly in sw2 bypass
I can sort of see how that might happen
^and dry is not fully dry now..when fully CCW
That has me scoobied. Any chance you could post a latest schematic?
yep, sure..
the sw2 definately pops whatever i do, breadboard this very carefully more than several times, but no joy... :)
(https://dl.dropboxusercontent.com/u/7464107/moddedmerlins.jpg)
^the sw2 definately pops whatever i do
have you tried large (e.g. 1M) pull-down resistors from SW2 lugs 2 and 3 to ground?
It's not obvious why you shouldn't get fully dry signal with the circuit as drawn, but then I'm probably missing something.
Other observations:
You probably don't need R11.
It looks like your dry signal in tails should be significantly below unity gain (22/57), but I'm guessign that is not the case?
tried the 1M resistors to ground...no joy, still pops like a mutha..
if i remove R11 / 33k from vb, i lose all verb..
unity is pretty good,TB/SW2 bypass/dry (there is just a tad of verb when 'dry') etc... fair bit of tonal difference , but that can be tweaked to taste later on..
think i may have to go with the 'reverb level' original pot from pin 13 after R8...vb etc...see if that helps with the pop issue as it wont be looping back to the sw2.
just thinking aloud....and go back to the wet/dry to pin12..hmmm...
as this had no pop issues a all..the sound clip was recorded in one hit while switching...so that loopback from mix to sw2 is the culprit ...i think.
http://www.diystompboxes.com/smfforum/index.php?topic=101126.msg941919#msg941919
^if i remove R11 / 33k from vb, i lose all verb..
That I don't understand either. At the moment, IC2d is just an inverting amp, just like IC2b and IC3b, so shouldn't need a bias restor to (+) input to function.
^unity is pretty good,TB/SW2 bypass/dry
As drawn, TB should be about twice as loud as SW2 bypass. Is R22 really 47k?
unity: yeah sorry that is back to 10k... (didn't have my DI box plugged in to mixer.was messing around last night etc...) better now. 8)
hmmm yep if i take that R11 out defo get no verb.. ???
out of curiosity i went back to the original switching with the 2x1k's/2x47k's...and it is dead silent...no pop at all even with mixer maxed out... 8)
BINGO!!!!... DEAD SILENT SWITCHING..AT @#$%ING LAST!!!!!!!!... :icon_twisted: :icon_twisted: :icon_twisted: :icon_twisted: :icon_twisted:
the culprit was the 10uf after R12, replaced that with 1uf np, and now its totally silent even with mixer full up..yay!!! 8)
and as a bonus the feedback/decay is bang on too.... 8) 8) 8)
man, there was more than a few times that my breadboard was going out the window with this bugger.....but am glad i stuck with it.
as we cured one issue another rose its ugly head etc...phewwwwwwwwww....that was the longest headache ever...for a few of us too. ;)
now to have a little tweak here n there and add the hi/lo switch back in. 8)
that 33k (R11) definately has to be there btw.
tweak..tweak... :)..going to try out a tone control instead of damp too. 8)
man, i'm having a fireworks night beer or 2 tonight to celebrate...hic! :P
Great! I'm ordering parts ...
Kick-ass, once you post a final schematic I might work on a layout in eagle if that's OK...
nice one Rob.
Nice one!
Might have to build another DA reverb now... :D
Excellent news! Can't wait to build this one!
Quote from: samhay on November 01, 2013, 12:23:12 PM
^if i remove R11 / 33k from vb, i lose all verb..
That I don't understand either. At the moment, IC2d is just an inverting amp, just like IC2b and IC3b, so shouldn't need a bias restor to (+) input to function.
The (+) input does need to be connected to Vb, it just doesn't need to be connected through a resistor- a direct connection is better (resistor just adds noise). I think Deadastronaut may have simply misinterpreted and removed the resistor altogether, breaking all connection with Vb.
Quote from: alanp on November 02, 2013, 01:55:53 PM
Kick-ass, once you post a final schematic I might work on a layout in eagle if that's OK...
BTW, If anyone was to get some pcbs fab'd, I'd put my hand up for one - I had a headache soldering the self-etched board last time, because of the tiny traces..
Quote from: merlinb on November 03, 2013, 07:04:43 AM
Quote from: samhay on November 01, 2013, 12:23:12 PM
^if i remove R11 / 33k from vb, i lose all verb..
That I don't understand either. At the moment, IC2d is just an inverting amp, just like IC2b and IC3b, so shouldn't need a bias restor to (+) input to function.
The (+) input does need to be connected to Vb, it just doesn't need to be connected through a resistor- a direct connection is better (resistor just adds noise). I think Deadastronaut may have simply misinterpreted and removed the resistor altogether, breaking all connection with Vb.
Good point...
Oh, and Rob, have you worked out how to do the switching with this now that it is working.
hi sam, guys..
not yet, spent a day recovering yesterday, celebrated a little too much...(i need to respect that famous grouse whiskey a little more) :P
anyway, this will be a lot of fun using a footswitch to play over the trails...and just have a toggle for TB . thats the way i fancy it anyway. 8)
ok, here is what i have now, the basic 'no frills' reverb. without hi/lo switching,
going to try out a tone control instead of that moody damp pot..
(https://dl.dropboxusercontent.com/u/7464107/DAREVERB2013BASIC.jpg)
Quote from: deadastronaut on November 04, 2013, 07:09:17 AM
ok, here is what i have now, the basic 'no frills' reverb. without hi/lo switching,
You need a resistor between the volume pot wiper and C1, otherwise the pot can short the (-) input of the opamp to ground. 1k will do.
okey dokey, schemo ^ updated.
notes:
the overall volume works with both reverb and sw2 bypass.
there is oscillation just using the 33k.( R5)
btw i have 3pdt toggle switches too...
edit: correction, vol works only in reverb...
there is a tiny tonal difference between TB and sw2 bypass....but very tiny.. :)
Quote from: deadastronaut on November 04, 2013, 07:49:17 AM
edit: correction, vol works only in reverb...
If you want a master volumr control that is active all the time, then replace R2 with a variable resistor. I'm not sure why you would want to do this though. Surely you would always want unity gain in bypass mode?
yeah thats not a problem merlin...
i was just making notes for myself really.. ;)
I think this will work for the switching (foostwitch on the left).
(https://dl.dropboxusercontent.com/u/11996927/Tails_switch_2.jpg)
nice one sam...
thats a mad setup eh.. ;D
just been tinkering with the feedback/decay resistors. 33k mass osc/ 100k tameable even fully on. (for more subtle reverb stuff)
so if we went with just buffered bypass, tails...( which i am coming round to thinking that's all i would use in the real world anyway)
no tails = nasty..
we could make life (switching) nice and simple eh.. 8)..plus the buffer near the end of my chain might be handy too..hmmm..
thoughts?.
hell we could just use a nice alpha DPDT ..and 2 leds.. 8) (ignore the resistor values etc)
(https://dl.dropboxusercontent.com/u/7464107/dpdtleds.jpg)
hmmmm...bummer, i can still notice a tiny pop still when ''playing and switching only''.... :(
doesn't pop when inactive though.....bugger i thought that was cured.. :-\
https://dl.dropboxusercontent.com/u/7464107/poppydaybummer.mp3
i'll try 1M resistors to ground on SW 1 3...see if that finally nails it totally. edit( nope)
yeah - the switching idea needs testing and it would be a lot simper if you were happy to do away with true bypass.
Good luck with the pop.
yep i think we'll do away with TB...sounds great as buffered anyway..
apart from this damn @#$%ing @#$%er pop, its only whilst playing though...hmmmm strange... :-\
no love for a poppy switch then?..
heres a clip of switching constantly through silence, great, until you play (which i why i thought it was cured) then it pops like a mutha with sound going through it,...then disappears as the 'sound' fades off too...
https://dl.dropboxusercontent.com/u/7464107/popperpig.mp3
ive tried 2.2M resistors to ground from out of input and output caps ..as option 2 suggested by RG (geofex) the 3rd option he gave was 'live with it' ::)
ive tried 2.2M's from sw2 lugs to ground also....kinda running out of ''not wanting to live with it'' options... :-\
any ideas?.
Quote from: deadastronaut on November 05, 2013, 07:13:11 AM
it pops like a mutha with sound going through it,...then disappears as the 'sound' fades off too...
Do you still get any voltage on the switch?
0v on both sides...
and 0v when being strummed on both sides..weird!.
What happens if you replace C15 with a smaller (preferably non-polarised) cap?
Edit: Did you true a pull-down resistor from lug 2 of SW2?
I know it's a long shot, but does it still pop with the LEDs removed from the circuit?
Quote from: samhay on November 05, 2013, 08:58:09 AM
What happens if you replace C15 with a smaller (preferably non-polarised) cap?
Edit: Did you true a pull-down resistor from lug 2 of SW2?
yep tried replacing that cap, no joy..
sw2: . resistor to ground instead of just ground, yep but still pops and lets reverb through too.
@bugg: there is no led in the circuit yet..(the above switching was for when it was sorted..)
i think we may have to go the electronic switching route...slackers echo base type thing. :icon_idea:
I think i have some 4066's..from when i built it.
what about these?..from andrew
http://www.thetonegod.com/tech/switches/switches.html
Quote from: deadastronaut on November 06, 2013, 03:50:32 AM
yep tried replacing that cap, no joy..
sw2: . resistor to ground instead of just ground, yep but still pops and lets reverb through too.
The cap was a long shot.
I meant a pull-down resistor from the switch side of R21.
Electronic switching is not guaranteed to be pop-free either, but it may be an interesting learning experience.
yeah i tried pulldowns on both sides of sw2 at those points...
yeah i guess there are no guarantees with electronic switching either...
it will add a lot more to the circuit, but IF it works, it will be worth it to have 'clean' switching on this..without reverberating pops ::)
i don't quite understand the schematics for this switching though..its something ive never dealt with, so it will be a learning curve for sure...
and how it would be incorporated into the schemo...hmmm..
take this SPDT version for example as i think i have 4066 and a 4093.. ( lifted from andrews the tone gods site )
(https://dl.dropboxusercontent.com/u/7464107/4066%2B4093.jpg)
so the spdt is a physical switch..(as in footswitch)
and the result is a virtual ( where we connect to where the sw2 was? ) but only using 2 connections?.
So if my head is on straight, it should be like this then..
but just take 2 switches out for the R21/R22..thoughts?
(https://dl.dropboxusercontent.com/u/7464107/406640932.jpg)
seems like a tank to crack a nut....but hey if it works.. :)
just for my own reference..
(https://dl.dropboxusercontent.com/u/7464107/40934066SWLAYOUT.jpg)
I'm not sure how happy the 4066 is when playing with signals that are swinging around ground. Isn't most of Andrew's 'wicked switches' about biasing up to half supply to prevent popping?
Edit: http://www.diystompboxes.com/smfforum/index.php?topic=74935.0;wap2
There is more out there, but my memory is failing me at the moment.
hmmm not sure!..
edit: resistors to vb on inverter inputs?.
^you mean the switch going to Vb.
It is a bit more complicated than that, but got me thinking about one other thing you can try - DC coupling most of it.
You could even remove C5 and/or C13 if you wanted, but they are probably doing some useful filtering.
The feedback, mix and volume pots now have DC on them. You might find this distasteful, but it is probably not an issue.
(https://dl.dropboxusercontent.com/u/11996927/DAREVERB2013BASIC_dc-coupled.jpg)
^ right i see...remove C2/ C1 / C15..
i'll give that a whirl... 8)
edit: WHOOOAHH... deadly massive pop.
did you see that the feedback and volume pots now connect to Vb?
oops no...ok i'll try again. 8)
nope that pops like hell..
I assume the 3 switch lugs are all at Vb now?
Is the popping worse this way?
sw at vb..
you mean with the caps removed etc..
i didn't measure the sw lugs, but it was massively popping..
its quite a little bugger as it only pops while playing and switching, when no sound is going through its as totally silent when switching...hmmm..
Hmm, there is probably a clue in that somewhere.
Do you fancy any more experimentation? If so, here are a couple of things to try:
- does it pop when the volume is all the way down?
- make R22 1k and R12 22k - any change?
yep there is still a little pop with reverb vol fully off..
no difference on swapping/changing the resistors.
i was looking at sabrotones reverb by harald..but i bet that pops too..
http://www.sabrotone.com/?attachment_id=2763
It might, but it's working a little differently - the dry signal is never lifted (it won't do 100% wet) and is high-impedance going into the non-inverting input of the output op-amp.
The bypass arrangement you have came from slacker right? Might be time to see how much joy he has had with it in the real world.
Edit - actually, thinking of slacker. You could try to go back to FET switching and use his FET switch-with-an-RC (http://www.diystompboxes.com/smfforum/index.php?topic=101126.msg939855#msg939855). You can still do the switching with a DPDT this way...
yeah, i'll ask him by pm and see if his experience is any different..
going back to the electronic switching..
what was the bias lark?..
If I recall, the bias lark involves putting the signal at Vb, which is what you had on the breadboard earlier today.
For another approach, see my last post - you would need two FET switches.
ok, cheers man, i'll check that out. 8)
2 fet switches?..
Not sure if you've seen this before, Rob (or if it's already been mentioned in this thread), but R.G. (who else?) has a handy article on CMOS switching here (http://www.geofex.com/Article_Folders/cd4053/cd4053.htm). Talks about biasing, too.
cheers marc: i was looking at the 4066+4093 setup as i have those..
but will they be properly 'silent' though?
Quote from: bluebunny on November 06, 2013, 10:11:43 AM
Not sure if you've seen this before, Rob (or if it's already been mentioned in this thread), but R.G. (who else?) has a handy article on CMOS switching here (http://www.geofex.com/Article_Folders/cd4053/cd4053.htm). Talks about biasing, too.
Ah, that's what I was think of.
@sam: 2 fets?..
1 to switch bypass etc..
1 for led?..is that what you mean?.
nope - One for each side of the SPDT you are using at the moment (they both go to ground, obviously) - as you turn one on, you turn the other off.
sorry man, i'm lost.. diagram?. :)
Sorry - numbering is not right, and I don't think I have drawn the FET switch correctly, but the DPDT wiring should give you the idea.
I have drawn it with the FET shunting to ground like the switch does at the moment. It would probably make more sense to put the switches in series like you did in the old bread board version.
(https://dl.dropboxusercontent.com/u/11996927/tmp06nov13.jpg)
The JFET switches approach is one I've suggested privately to DA.
I would do it a bit differently, as the exact source of the pop when signal is present is not clear, and as the JFET switching he did before did not kill the reverb signal.
I would use a combination of series/shunt switching. I'd use N-channel JFETs for the series switches and P-channels for the shunt switches, and float the whole thing on half of the 9V supply. That way, you can use one SPDT switch to operate the switching. The N-channels are followed by a P-channel. When you want the channel on, the N-channel needs a high input signal, which turns the matching P-channel shunt off and lets signal through. When you close a channel, a low signal turns the N channel off and the P-channel on, and gives better isolation than a single series switch. Unfortunately, you need two of these.
I would also buffer the signal after the switch before feeding the reverb. It is possible that this one step would fix things, as I have some questions about what happens to the signal to the reverb when there is signal present and the switch changes.
RG - I thought of using one N- and one P-FET in this configuration, but figured Rob probably doesn't have any P-FETs in his stash. If I'm wrong, then you can save yourself half a DPDT. The series/shunting switching is a good idea if this doesn't do a hard enough mute.
The signal is buffered before the reverb by IC2c. However, Rob - does the pop change depending on where the mix pot is set?
This is another way to do the FET switching. This time, the FETs are in series like the old version. Again, one turns off when the other turns on.
(https://dl.dropboxusercontent.com/u/11996927/tmp_07nov13.jpg)
hi sam .
pop is pretty much the same whether dry of half wet etc ..(just tried it through sound forge.)
and no i don't have any P FETS.. :)
i'll pop that 2 fet circuit on a seperate breadboard and link it over, cheers man. 8)
so i wire up the dpdt as above still?
nice to see R.G join in the headache too.. ;D ;)
yeah - footswitch is the same. The LED on the botton switch is your indicator, so isn't necessary.
Just check the FET switch is drawn correctly - it should be the same as the version you tried with slacker's 'slow switch'.
yep, looks the same as ians 'slow switch' ... 8)
Quote from: samhay on November 07, 2013, 04:39:06 AM
RG - I thought of using one N- and one P-FET in this configuration, but figured Rob probably doesn't have any P-FETs in his stash. If I'm wrong, then you can save yourself half a DPDT. The series/shunting switching is a good idea if this doesn't do a hard enough mute.
The signal is buffered before the reverb by IC2c. However, Rob - does the pop change depending on where the mix pot is set?
This is another way to do the FET switching. This time, the FETs are in series like the old version. Again, one turns off when the other turns on.
Change R10 to 10k and move it to the other side of R21 (do the same things for R12). This will improve the offness, with negligible change in on-ness.
R21, 1k
JFET----o----/\/\/\---
|
|
| |
| | R10, 10k
| |
|
|
Vb
right, soldered up my switch, got it on breadboard wired etc..as per schemo (will try merlins suggestion in a bit ;))
the good news.. very , very silent switching back n forth whilst hammering a chord etc...excellent. 8)...even with the led so i could tell it was on/off..
but, the weird news is, when bypassed i get a few seconds of clean then the reverb oscillates and rises through..to mass oscillation
this is how i wired it up..
(https://dl.dropboxusercontent.com/u/7464107/ANTIPOPSWITCH.jpg)
i will now try merlins suggestion too.
edit: oops missed the note about R22.. ::)
EDIT: yep still osc on bypass..
Well that's mostly good news I guess.
Merlin's suggestion might help as it will keep the wet side of the switching relatively low-impedance. If not, you might want to try the other FET switching idea.
yeah the switch is nice , very promising.... 8)
so i just take vb from between R10/R21...when i put them in series..then 10uf >?
edit: tried that but get massive oscillation on both on/bypass..
if i change R21 /1K to anything else its wild osc...
heres how it behaves as per schemo..no pop..but osc on bypass.
https://dl.dropboxusercontent.com/u/7464107/tester.mp3
Quote from: deadastronaut on November 07, 2013, 07:23:42 AM
edit: tried that but get massive oscillation on both on/bypass..
if i change R21 /1K to anything else its wild osc...
That's one of the reasons I suggested that you buffer after any switching. A low impedance source to both the reverb input and to the bottom of the reverb mix will effectively keep the reverb from feeding back into itself. That's why a 1K works there - it's just low enough to keep the oscillations out.
If you can get enough isolation from a simple series JFET switch, you may be OK with just buffering after the switch into the reverb section.
^ cheers R.G.
for my own reference, and you guys too, i'll stick this up (how i have it at the moment)
(https://dl.dropboxusercontent.com/u/7464107/REVERB2FETS.jpg)
sorry its small, i had to adjust things to A3 in my editor.. ::)..i can blow up (bad choice of words :P) the image if needed. :)
now this buffer lark?.. :)..from C4/C9 ?..
You've drawn the footswitch incorrectly - only one FET gate should be connected to V+ at a time.
oh yes..of course.
i'll correct it. cheers sam. 8)
edit: corrected: :)
so which buffers..and where to put them. straight from C4 . and straight from C9?
Bottom buffer here?..(but using 072) wil this then make the overall output non inverting too? as well as sort feedback bleed over on bypass...questions , questions.. :)
http://www.muzique.com/lab/buffers.htm
btw i tried the switching out today again, no noise whatsoever as it is....excellent'e 8) 8) 8)
If you want to use a discrete transister, then a common drain MOSFET buffer could go between R11 and C4 and will only cost you a FET + 1 resistor.
Oh - you almost certainly don't need to buffer the dry side of your switch.
cheers man, i have a 2n7000, but no 9v zener diode ...hmmmm..(looking at the link mosfet buffer)
i also have fets j201'5458/5457's..
The Zener isn't especially crucial in this application - it is to prevent the FET getting zapped by the outside world, and the input buffer aught to prevent that.
ahh brilliant..thanks man.
just added it to the schemo..i'll give it a whirl then. hopefully were sorted!. 8)
right, done that, used a 2n7000 / 2.2k on source....it works and stops the bypass feedback osc etc... 8)
but there is a teeny little tick when reverb goes on..
however switchig to bypass seems to be totally tickless.
heres a clip of what i mean, at the end of the clip as the note fades i'm switching on/off all the time..silence.
https://dl.dropboxusercontent.com/u/7464107/testverbtick.mp3
pulldown resistor maybe?
I'm guessing, but it might help if you make R11 smaller.
aha...by jove i think we have a tickless switch... 8)
i used my resistor sub box...took it down to 100k...still a tiny tick..
down to 56k..gone!!!!! whoooooohoooooooo...excellent..thanks a bunch man, i owe you a beer or 1000.. ;)
i'll test it out some more, before i get too excited, i have mass delay on the reverb so i can hear any tick repeated loudly and it seems fine at the mo...
i''l try a test recording... ;)
edit:
seems really cool...no noise so far...sounds awesome ( not a word i use often ) ..this is with mix fully wet.
https://dl.dropboxusercontent.com/u/7464107/reverbticktest.mp3
i fancy i'll build 2 of these buggers eventually....one for pure ambient, other for normal verb stuff..nice 8)
excellent
As a spectator since the single digit pages, I have to say I'm releaved this is worked out. You guys put some serious time and brain power into this. Congratulations! The circuit sounds fantastic.
Matthew - have you checked out chromesphere's youTube vid of this circuit? It's luvverly :D
@matthew: yeah its been a real pita and headache, but very well worth it...thanks to sam's patience..and a lot of rejigging on breadboard/schematics 8)
here is my check list of stuff to do today:
hi/lo switch: no longer needed. check.
osc/normal switch: no longer needed as it will osc nicely on 33k-82k anyway . check.
: try different fets (rather than use up my precious j201's up) .........to do
: try a tone control, rather than damp. (which works fine, but as i have it on breadboard might as well experiment a little ) .........to do
: check buffered bypass against true bypass for any tonal differences......to do.
: cook poached eggs in baguettes, have a coffee, and feed the cat. ....to do now. ;D
was playing around last nght with the verb with phaser/chorus and delay after...chorus and phaser sounds great on trails , which got me thinking about lfo modulation on the verb....arghhhhhhhh i hear you scream!!!!. :D
just a thought though... ;)
Quote from: deadastronaut on November 10, 2013, 05:26:54 AM
was playing around last nght with the verb with phaser/chorus and delay after...chorus and phaser sounds great on trails , which got me thinking about lfo modulation on the verb....arghhhhhhhh i hear you scream!!!!. :D
Rather than built in modulation, what about an effects loop for the wet signal?
That would be priceless.
hmmm yummy. 8) good idea. :icon_idea:
Musical modulation may be difficult-to-impossible. The tricks used for modulation of single PT2399s wiggle either the delay resistance or Vb voltage IIRC. Neither of these are possible with the BTDR-1/2 as there are no decay or Vb pins.
However, there is a new BTDR-3 brick (search over at the other forum), which has a variable decay/depth option that one could wobble. Not sure if this is similar to the feedback arrangement that the current circuit uses or whether it allows the delay of the one of the PT2399s to be tweaked.
You could modulate the feedback relatively easily (essentially put a tremolo in the feedback path).
I guess you could also try modulating the supply voltage of the BTDR, as this will probably cause all manner of weirdness. You could use an LM317 and wobble its control resistor(s). This sounds like an easy way to fry a brick, but might be worth a try - will put on my list.
Oh - and there is already an LFO in the BTDR bricks, which is why you can just about hear a modulation in the wet effect.
hmmm interesting...don't fancy frying my brick though.. ;D
buggs idea might be cool though. effects loop on the wet. :icon_idea: then lob anything through it.
edit:
this is meant to be with the newest verion brick..hmmm.....not impressed....no tails, no full on wet hall/osc etc etc.....ok if your into rockabilly stuff i guess, ..just not for me. ;)
http://www.youtube.com/watch?v=zcUPjeFNMWE#t=813
probably fun to mess with the brick though...and squeeze the living daylights out of it.. ;D
edit:
this inverting/non inverting lark..wouldn't a phase switch on the output sort that?...kid of like this. (which i used for a diy sustainer flipping coils)
(https://dl.dropboxusercontent.com/u/7464107/3pdtDRIVERWIRING.png)
For your buffer, try a Tillman preamp. It's a little more boost than you might have been considering, but you've already got a volume control to tame it. It could be made to work with other JFETS than a J201. Tillman originally used a 2N5457, but he found the J201 to be less noisy. I used the Tillman in my Pulsinator and it worked great.
http://www.till.com/articles/GuitarPreamp/
cheers john, buffers sorted... ;)
am tinkering with the fet switch (ians slowed down) ones..to make them quicker.
as there is a slow rise and fall effect when switching over..but having good results so far...tinker tinker..
any comment/opinion on the 'phase' switch ?..(to make it invert / non inverting)
I have never seen a phase inverter like that in a stompbox, and I think your idea needs one side of the ground to be floating.
hi sam, yeah pretty crude, it worked on my diy sustainer for fundamental/harmonics , was just curious to see if it could be applied to this...hmmm..
anyway i figured why i had a sudden fall when switching.......sorted. ;)
Rob- I'm ordering parts to build this puppy. Are you still using the BTDR-2H?
Edit: just realized that H stands for horizontal.
What I meant to ask is are you using short, medium, or long?
(Sorry-I read at a few pages of the thread, but didn't read all 34. ;) )
hi john, yeah its the BTDR 2-H L long.....as long as this thread, and the time its taken to sort it.....but totally worth the time and trouble..
the only problem is i go to tweak it and just end up playing for ages.....now that's a sign of a goodun, it'll be a permanent resident on a board for sure !! 8)
I also have a question about the Belton brick.
I made a mistake during my last order and I received a BTDR-1.
Could a BTDR-1 be used in your circuit and/or other circuits designed around a BTDR-2?
There are two output pins on the BTDR-1 but I can't find any information on the internet whether those are two true outputs like the BTDR-2 (for stereo application for example) or not. ???
@loylo: hmmm.. here is the data sheet schematic for your brick ( courtesy of smallbear)
https://www.smallbearelec.com/Projects/ReverbPedalSchematic.pdf
totally different pinouts etc i'm afraid, ..and its a short reverb. :-\
The BTDR-1 should work in this circuit BUT the pinout is different, so any PCB art will not work and it draws more current than a BTDR-2, so I would use a 7805 voltage regulator (rather than a 78L05).
The short or medium bricks will sound different to the long brick, but will still work. With the feedback working so well now, a short brick may actually be more versatile.
Quote from: samhay on November 13, 2013, 10:00:16 AM
The BTDR-1 should work in this circuit BUT the pinout is different, so any PCB art will not work and it draws more current than a BTDR-2, so I would use a 7805 voltage regulator (rather than a 78L05).
The short or medium bricks will sound different to the long brick, but will still work. With the feedback working so well now, a short brick may actually be more versatile.
I can report the medium brick sounds amazing. The oscillation switch does not actually reach oscillation; however, it does swell nicely and sounds fantastic in tandem with an analog delay. This will probably be my "daily driver" once the click noise is sorted...
edit: I'm building a couple up off of the v1.6 RO Tiree boards. What modification must I make to get the noiseless switching?
edit 2: R14, perhaps?
Hi deadaustranaut
I've been reading this post and Man... After ear some of the demos... Congrats... It's a sweet reverb machine that you have here...
I use mostly the rub a dub but i want to give a try on your baby...
I see that there is a lot of changes going on so my question is should I build the last file project that you post or should I wait a bit more to let all of this changes take place?
A big shout
Sérgio
Thanks deadastronaut and samhay! :icon_smile:
I know the pinout is different and I'd have to change the layout if I take BTDR-2 design.
I think I'll test your design, deadastronaut, so that's nice if the BTDR-1 works.
And what if I try to make your own "another BTDR reverb", samhay, with the BTDR-1?
I wonder if the two outputs of BTDR-1 would allow me to take the feedback path from the second output and work like your BTDR-2 design?
Quote from: loylo on November 15, 2013, 02:10:57 PM
Thanks deadastronaut and samhay! :icon_smile:
I know the pinout is different and I'd have to change the layout if I take BTDR-2 design.
I think I'll test your design, deadastronaut, so that's nice if the BTDR-1 works.
And what if I try to make your own "another BTDR reverb", samhay, with the BTDR-1?
I wonder if the two outputs of BTDR-1 would allow me to take the feedback path from the second output and work like your BTDR-2 design?
You're welcome.
As far as I know the BTDR-1 and BTDR-2 are equivalent ICs in different packages. Shrinking the package in the BTDR-2 reduced the current consumption, but otherwise I would expect the two bricks to behave the same. I may be wrong, but I haven't heard anything to this effect.
So... the BTDR-1 should (but may not) work just fine in any of the circuits designed for the BTDR-2 and I see no problem using it in my 'Another BTDR reverb'. I would be interested to hear your experiences, and would encourage you to try it on the breadboard first.
i have designed and made a pcb, and gone over it carefully for any errors, but all checks out..
populated it now, am just finishing up wiring/and 1590bb box etch design .....then test it thoroughly.
bought a couple of nice ALPHA non clunky DPDT footswitches, so should be nice and quiet... 8)
i'm busy today , but should be done by early next week...hopefully...
if all goes well i will make a batch of pcbs available ok...
note : due to the recent 'brazillian ripping me off' incident, i will only be sharing a link to the layout files by pm only...as i'm @#$%ed off with doing months of hard work
only to be taken the p.ss out of, and seeing that hard work used for commercial purposes and even my video demo's too for @#$%s sake ::),
even when i ALWAYS state ''not for commercial use'' ...sorry but that's the way its got to be, as some @#$%ers don't seem to understand that phrase... :icon_evil:
rant over...
back soon with results.. :)
Quote from: deadastronaut on November 16, 2013, 07:10:09 AM
if all goes well i will make a batch of pcbs available ok...
*thumbs up*
[/quote]
Put me down for one.
Will definitely need to pick up a PCB, only thing my pedal board is missing is a good reverb! Seen poodle has some bricks in the UK, might hold off on getting his PCB and try this one instead.
Good news then... I want one... My favourite effect
Eu quero um também.
fair enough Rob. Are you going to post a final schematic?
I hope this doesn't derail this thread but I just have to mention it and seems like the place to ask. Has anyone built something from one of these before? 16 effects in one, includes the reverb effect im assuming is the same as the one we are hearing with the flying saucer reverb:
http://www.accutronicsreverb.com/ (link is on the left hand side, BTSE-16FX)
The example circuit looks suspiciously simple
Hmmm, this could use a new thread perhaps...
Here's a direct link to the PDF:
http://www.tubeampdoctor.com/images/File/BTSE-16FX_%20Accutronics%20DIGITAL%20SOUND%20EFFECTOR.pdf
Culturejam mentioned no user controllable parameters (in another thread), which sucks abit but I would still be interested hearing it in action.
This should probably be a new thread. The "Flying Sauce Effector" thread? :D Sorry rob, ill leave the conversation here.
Paul
Quote from: samhay on November 16, 2013, 06:21:40 AM
You're welcome.
As far as I know the BTDR-1 and BTDR-2 are equivalent ICs in different packages. Shrinking the package in the BTDR-2 reduced the current consumption, but otherwise I would expect the two bricks to behave the same. I may be wrong, but I haven't heard anything to this effect.
So... the BTDR-1 should (but may not) work just fine in any of the circuits designed for the BTDR-2 and I see no problem using it in my 'Another BTDR reverb'. I would be interested to hear your experiences, and would encourage you to try it on the breadboard first.
You're right, I'll have to test if the BTDR-1 behave the same way as the BTDR-2 is supposed to.
I'll report it back to you, for sure. :icon_wink:
moved to here:
http://www.diystompboxes.com/smfforum/index.php?topic=105109.new#new
Quote from: deadastronaut on November 20, 2013, 12:50:18 PM
moved to here:
http://www.diystompboxes.com/smfforum/index.php?topic=105109.new#new
nice one!
I'll have to really get around to opening mine up again and getting that oscillation happening, otherwise I might just have to grab one of your boards for down the track ;)
Hey Rob.. how hard would it be to turn this into a stereo reverb? The Belton Brick can do that, right?
Yes it can, check out all star reverb ii think that's stereo...
but yeah the brick 5 6 pins are outputs ...
Quote from: therealfindo on November 22, 2013, 04:13:04 PM
Hey Rob.. how hard would it be to turn this into a stereo reverb? The Belton Brick can do that, right?
As Rob said - not especially difficult. The application notes show how to do it. However, the signal coming out of the two outputs of the brick are, as far as I can tell, the same. So, you could turn it into a stereo reverb with a splitter cable and be no worse off.
If you want a stereo reverb where say one channel is dry and the other wet, than that might be more interesting (and is still quite easy to achieve).
Are there options to add a tails switch to the chasm reverb, killing the tails function (with a toggle) when no tails are desired? I don't mean that I want true bypass, I just want the option of having the tails selectable (as in the echo base).
You could replace the SPST switch with a stomp switch. Use a momentary switch if you only want tails while your foot is on the switch, or use a latching one if you want to take your foot off and keep the tails on. Does this sound like what you're asking?
Edit:
Maybe what I described only affects oscillation. I guess tails are a different animal.
Quote from: samhay on November 23, 2013, 06:53:18 AM
Quote from: therealfindo on November 22, 2013, 04:13:04 PM
Hey Rob.. how hard would it be to turn this into a stereo reverb? The Belton Brick can do that, right?
As Rob said - not especially difficult. The application notes show how to do it. However, the signal coming out of the two outputs of the brick are, as far as I can tell, the same. So, you could turn it into a stereo reverb with a splitter cable and be no worse off.
If you want a stereo reverb where say one channel is dry and the other wet, than that might be more interesting (and is still quite easy to achieve).
what about stereo input? e.g. running it after a stereo delay..
Quote from: deadastronaut on October 22, 2013, 06:04:13 AM
^ looking at R O trees schematic version it should be fine... the 33k swapped to 22k should osc like hell.
is your feedback pot ok?....is it doing anything?.
OK, finally got around to opening it up again...
I checked all the solder joints.. no change. I swapped the switch wiring, no change..
Now the interesting bit - I took the 33K (R13 in the layout: http://www.diystompboxes.com/smfforum/index.php?topic=101126.msg917324#msg917324) right out and no change. I still had the 22K in place of the 68K in the switch part, and that is no longer in the circuit either.. still no change.. Should I have heard a difference removing that 33K resistor?
I've looked over the traces a bunch of times and can't see any bad connections.. any other ideas?
Quote from: Jdansti on November 23, 2013, 11:44:04 AM
You could replace the SPST switch with a stomp switch. Use a momentary switch if you only want tails while your foot is on the switch, or use a latching one if you want to take your foot off and keep the tails on. Does this sound like what you're asking?
Edit:
Maybe what I described only affects oscillation. I guess tails are a different animal.
Tails is indeed something else ;)
D'astro, do you have a final schematic? That would help me understand a bit more about the bypass and the wet signal and how to add a tails/no tails switch to this superb reverb.
Quote from: samhay on November 16, 2013, 06:21:40 AM
You're welcome.
As far as I know the BTDR-1 and BTDR-2 are equivalent ICs in different packages. Shrinking the package in the BTDR-2 reduced the current consumption, but otherwise I would expect the two bricks to behave the same. I may be wrong, but I haven't heard anything to this effect.
So... the BTDR-1 should (but may not) work just fine in any of the circuits designed for the BTDR-2 and I see no problem using it in my 'Another BTDR reverb'. I would be interested to hear your experiences, and would encourage you to try it on the breadboard first.
A bit off topic, but after my test, the BTDR-1 seems to work exactly the same as the BTDR-2 is supposed to: the two outputs can also be summed up although the datasheet of the BTDR-1 don't mention it (the BTDR-2's datasheet do).
So the difference between the 2 versions of the brick is only the smaller package in favor of the 2nd version.
It's time for me to test the CHASM Reverb with my BTDR-1! :icon_biggrin:
^ cool, let us know how you get on.
@yorick , pm'd.
Quote from: loylo on November 25, 2013, 11:11:53 AM
Quote from: samhay on November 16, 2013, 06:21:40 AM
You're welcome.
As far as I know the BTDR-1 and BTDR-2 are equivalent ICs in different packages. Shrinking the package in the BTDR-2 reduced the current consumption, but otherwise I would expect the two bricks to behave the same. I may be wrong, but I haven't heard anything to this effect.
So... the BTDR-1 should (but may not) work just fine in any of the circuits designed for the BTDR-2 and I see no problem using it in my 'Another BTDR reverb'. I would be interested to hear your experiences, and would encourage you to try it on the breadboard first.
A bit off topic, but after my test, the BTDR-1 seems to work exactly the same as the BTDR-2 is supposed to: the two outputs can also be summed up although the datasheet of the BTDR-1 don't mention it (the BTDR-2's datasheet do).
So the difference between the 2 versions of the brick is only the smaller package in favor of the 2nd version.
It's time for me to test the CHASM Reverb with my BTDR-1! :icon_biggrin:
good to know. Thanks.
Quote from: therealfindo on November 23, 2013, 11:50:27 AM
Quote from: samhay on November 23, 2013, 06:53:18 AM
Quote from: therealfindo on November 22, 2013, 04:13:04 PM
Hey Rob.. how hard would it be to turn this into a stereo reverb? The Belton Brick can do that, right?
As Rob said - not especially difficult. The application notes show how to do it. However, the signal coming out of the two outputs of the brick are, as far as I can tell, the same. So, you could turn it into a stereo reverb with a splitter cable and be no worse off.
If you want a stereo reverb where say one channel is dry and the other wet, than that might be more interesting (and is still quite easy to achieve).
what about stereo input? e.g. running it after a stereo delay..
The brick has only one, mono, input. If you run the reverb after a stereo delay, you will need to sum the stereo signals into one mono signal and send it through the brick, defeating the purpose of the stereo delay. You could tap both outputs of the brick, but it would be basically two mono outputs/no longer 'stereo' as the delay before it.
You would need to run two bricks to keep the audio stereo, one for each of the delays outputs. Then you wouldn't need to sum the signal and lose the stereoness.
Bump..
Quote from: therealfindo on November 24, 2013, 07:14:01 AM
Now the interesting bit - I took the 33K (R13 in the layout: http://www.diystompboxes.com/smfforum/index.php?topic=101126.msg917324#msg917324) right out and no change. I still had the 22K in place of the 68K in the switch part, and that is no longer in the circuit either.. still no change.. Should I have heard a difference removing that 33K resistor?
I've looked over the traces a bunch of times and can't see any bad connections.. any other ideas?
Anyone?
Quote from: therealfindo on November 24, 2013, 07:14:01 AM
Now the interesting bit - I took the 33K (R13 in the layout: http://www.diystompboxes.com/smfforum/index.php?topic=101126.msg917324#msg917324) right out and no change. I still had the 22K in place of the 68K in the switch part, and that is no longer in the circuit either.. still no change.. Should I have heard a difference removing that 33K resistor?
I've looked over the traces a bunch of times and can't see any bad connections.. any other ideas?
If you have replaced R13 with a 22k resistor and removed the OSC switch, then it will, if built and wired correctly, oscillate when the feedback pot is maxed out.
Does the feedback pot do anything? If not, are you sure that lug 1 is grounded?
Quote from: samhay on November 26, 2013, 04:35:46 AM
If you have replaced R13 with a 22k resistor and removed the OSC switch, then it will, if built and wired correctly, oscillate when the feedback pot is maxed out.
Does the feedback pot do anything? If not, are you sure that lug 1 is grounded?
I've replaced R13 with a 22K and the switch is out of the circuit - still no oscillation. The Feedback pot IS working (to some degree at least) but no oscillation when it is maxed out.
Lug one of the Feedback pot is not grounded - as the board / layout doesn't ground it - and indeed, when I did ground it, it kills the signal..
:icon_redface:
I've made a terrible mistake.
I have actually labelled my Damp pot as the feedback - so the Damp is working, it seems.. but yeah, the feedback isn't doing anything (and you are right, the 1 lug should be grounded.. I was following the damp pot wires back to the board!!)
are you using the schemo/layout with the 33k/68k in parallel ?...
Quote from: deadastronaut on December 01, 2013, 01:21:37 PM
are you using the schemo/layout with the 33k/68k in parallel ?...
Yep, v1.6 - but I've taken the switch out and swapped the 33k to a 22k for the moment, until I can figure out where the problem is... I might have to just etch a new board and try again from the start if I can't find the problem..
Hey Rob,
if I was to use your new tails version, but wanted to keep the box I've got with a reverb pot and bright switch, would that be easy to do with your new pcb? e.g., replace a resistor with pot / switch?
You could always build my original version layout with bright switch etc..
my pdf files are in the thread...just to save your box etc...just add a vol pot on the output...
Quote from: deadastronaut on December 01, 2013, 05:02:49 PM
You could always build my original version layout with bright switch etc..
my pdf files are in the thread...just to save your box etc...just add a vol pot on the output...
You mean without oscillation?
no, you could still have oscillation, just swap the 33k for a 22k/ maybe 10k..... (without a switch)
or if you want a switch have a 33k and 22k/maybe 10k on outer switch lugs...and connect switch middle lug to board (where 33k was)
and run both resistors to other side of where 33k was....
Well... I etched another v1.6 board, and was very careful with my soldering (those little traces take patience, and a thinner diameter solder I realised) and now I have one with oscillation.. hoorah! ;D
whoooooohooooooooooo merry xmas... ;D 8)
Quote from: deadastronaut on December 19, 2013, 07:58:23 AM
whoooooohooooooooooo merry xmas... ;D 8)
:)
My new amp (merry Christmas indeed!) doesn't have any on-board reverb like my old one did, and I really love the everything at 100% sound of this reverb for atmospheric picking (which would be really appropriate at times in church - but gets woolly for strumming and driven sounds) but then the reverbless sound of the amp when I bypass it is quite a shock.. so I might have to build another simpler 'always on' reverb..
But what if we could route the belton to two different sets of pots with a footswitch? The easy way would be to simply have two independent reverb units in one box with a switch between them or two bypass switches, but those bricks are not cheap.. is it even possible to swap the brick between two output circuits via a footswitch? (of course, the other option is to simply get down and twiddle knobs, but that's impractical during a set).
anythings possible i guess...within reason....do you mean having 2 preset pots..switching between?
on what pot though...the reverb level?
Ah, what the heck.. I'll just build a V2 - buffered w/tails - to go after it at the end of the chain! :icon_lol:
best of both worlds... 8)
Is the dry part of the signal still analogue? (just out of interest..)
Hey guys, could you take a look at this schematic? http://efekty-diy.pl/pdf/Reverb.pdf
I've build one but Im not quite satisfied with the quality, is there anything I can do to improve it? My reverb is only usable in first quarter of Reverb Pot, above that its just really echoing and very bathroom like. It also has springy sound at almost all settings. Maybe you know what to change to make it sound more like Flying Saucer?
^above that its just really echoing and very bathroom like
If one were to be uncharitable, that is how I might describe the Belton reverb brick sound.
^it also has springy sound at almost all settings
yep - it is supposed to emulate a spring reverb, and it does a pretty good job of doing so.
^Maybe you know what to change to make it sound more like Flying Saucer?
I could tell you to just build one of Rob's (or mine) reverb instead. However, the 'flying saucer' noise (good description) is, in part, a result of less filtering and more feedback than usual.
The attached schematic has feedback via RV1. If you want more, try reducing the value of R4. It should start to oscillate somewhere around 22k.
Filtering happens via RV2 and the 33n cap. If you use a smaller cap, you will get less treble loss and vice versa.
The other thing that you might want to try is to lift the dry signal to get a fully wet reverb. This may be even more 'bathroom' like, but is probably what you are hearing in Rob's clips. To lift the dry signal, lift one end of R10.
Edit: something like this? http://www.diystompboxes.com/smfforum/index.php?topic=107226.msg974393#msg974393
Thanks for the mods! I lowered the 33nF cap to 15nF and I think now its more like it :) Didnt like the oscillating mod, I have plenty of reverb to go on, actually its only usable in first 90 degrees of pot. I think Ill stick to what it is. The sound Im hearing may also be affected by my Noisy Cricket MKII. Im sure it would sound better with real amp :)
Quote from: Rethfing on May 23, 2014, 07:13:40 AM
Hey guys, could you take a look at this schematic? http://efekty-diy.pl/pdf/Reverb.pdf
I've build one but Im not quite satisfied with the quality, is there anything I can do to improve it? My reverb is only usable in first quarter of Reverb Pot, above that its just really echoing and very bathroom like. It also has springy sound at almost all settings. Maybe you know what to change to make it sound more like Flying Saucer?
That schematic is nearly an exact copy of the All-Star Reverb posted by induction over at the "Other Place." I built the All-Star and thought it sounded pretty good with a lot of versatility. I build mine stock, without the wetter mods that were posted. I'm no designer, but there seem to be a couple of key resistor values that may account for an imbalance between wet and dry. Maybe this one is like the "Wetter" mod for the All-Star?
I think this is the right thread - I have so many saved files called "DA Reverb <somethingorother>", that I can't be sure. Anyway, the one
before the CHASM...
| (http://www.bouron.org.uk/marc/darv420.JPG) | Just wanted to say that I took this for a bit of a road test yesterday, doing some recording for a mate. A small collection of my other builds (e.g. Engineer's Thumb, BSIAB2, Tube Reamer, ...) ultimately going into this, then into Rick's "Murder One" and an 8" Orange cab. It sounds feckin' gorgeous. :icon_cool: :icon_cool: :icon_cool: My mate was suitably impressed. Nice one, Rob.
[ Aside: Hmmm... everything between Fender/Gibson and Orange was from the Bunny-Boiler. How cool! ;D ]
|
^It's a good 'un! :D
Does anyone still have a copy of the schematic for this pedal? Whatever happened to "What happens on the internet, stays on the internet"?
great first post... :icon_rolleyes:
Quote from: deadastronaut on November 17, 2014, 05:22:24 PM
great first post... :icon_rolleyes:
Sarcasm aside, as you're the very specific reason I signed up at all, thanks!
Been working through tracking this one down for a while, and finally decided to go straight to the source.
;D
Hi xomby. Take a look at the "CHASM reverb"
Its the updated version...all info is there ok man.. ;)
Hi Rob,
can i need a reverb for my pedalboard.
Can you send me the final version (with tails) of this reverb?
Thanx
Tom
hi tom , so a search for "chasm reverb"
all docs there ok...