Some of you may remember my Equinox reverb: http://www.diystompboxes.com/smfforum/index.php?topic=93868.0 (http://www.diystompboxes.com/smfforum/index.php?topic=93868.0) which used two PT2399s in parallel for its reverb sound.
Having proved the concept I decided to simplify the circuitry by putting the PT2399s in series instead, so naturally it had to be called Solstice! It uses many fewer components since only two of the on-board opamps are now required, taking care of both the input and output filtering simultaneously. I also eliminated the fat/bright switch, since I never use it on anything but bright. Tail switching remains, naturalment.
Here is a quick sound clip. I recorded a sample into my computer and played it back through the Solstice, reverb at zero, then 12 o'clock, then maximum. Some EQ added later for a simple cab sim.
http://dl.dropbox.com/u/57831278/solsitce.mp3
Interestingly I think the Equinox sounded a bit more springy, whereas Solstice sounds a bit softer and more like a real hall...
Schematic, PCB and layout can be found here:
http://s81.photobucket.com/albums/j207/merlinblencowe/Solstice%20Reverb/
Also I have put everything (including BOM) into a single PDF:
http://www.freewebs.com/valvewizard2/solstice.PDF
The circuit is a bit big, so here is a basic overview of the topology for quick reference. Lots of fun to be had by varying the feedback and delay resistors. Various room, bathroom and metal box sounds are possible with modding, if not very useful... :icon_wink:
(http://i81.photobucket.com/albums/j207/merlinblencowe/Solstice%20Reverb/SolsticeTopology.jpg)
It doesn't look much on the outside yet, but I will update when I have finished decorating it (unless you're reading this in a year's time, in which case I have probably gotten around to it :P )
(http://i81.photobucket.com/albums/j207/merlinblencowe/Solstice%20Reverb/solstice1.jpg)
(http://i81.photobucket.com/albums/j207/merlinblencowe/Solstice%20Reverb/solstice2.jpg)
Just today I downloaded the Equinox documents to build for a friend...
Have to give this a try!
Thank you.
WOW! Another master craftsmanship! Great word merlin! Based from the sample. Equinox is more roomy(?-still love the switch ;)).
That's really neat! I thought about using 2 delay lines before, but never could brainstorm a way to make it work... man, I was way off! I gave up on it when you posted Equinox (that's when the realization hit, I think, that I had lots more to learn about delay stuff in general).
One idea I had that may be feasible is using a BBD like 3207 for the longer delay line, driven by buffered and divided down clock from the PT. I'm thinking (dangerous at times) that the difference in sound from the 2 lines would interact for some extra texture.
I really like the sound of this, I'll have a listen with something other than my phone speaker, but this might go into my next amp build.
This one sounds fantastic, and it's a nice change from all the Benton chip designs.
Your compressor is really cool, too, it's on my build list. This one's a little beyond perfboard, though ... I might have to get someone to etch it for me when I go to build an amp with no reverb. :)
another one. ;D
This sounds great! I'm in the process of building it and was wondering if it would be useful to move P2 off board and use a regular pot so that I could control the delay without opening the enclosure.
Quote from: Jdansti on May 22, 2012, 12:39:06 AM
This sounds great! I'm in the process of building it and was wondering if it would be useful to move P2 off board and use a regular pot so that I could control the delay without opening the enclosure.
Sure, knock yourself out! Personally I don't find it very useful, so I just drilled small hole in the bottom of the enclosure so I can twiddle the trimpot with a screwdriver.
Quote from: merlinb on May 22, 2012, 05:19:47 AM
Quote from: Jdansti on May 22, 2012, 12:39:06 AM
This sounds great! I'm in the process of building it and was wondering if it would be useful to move P2 off board and use a regular pot so that I could control the delay without opening the enclosure.
Sure, knock yourself out! Personally I don't find it very useful, so I just drilled small hole in the bottom of the enclosure so I can twiddle the trimpot with a screwdriver.
Good idea. Thanks!
Just finished testing my Solstice and it works great!!! (after remembering that my PS is center neg :icon_eek: thank you for the protection diode!)
Haven't boxed it yet, but here's the board. Most of my poly caps weren't as small as yours so I had to get creative with the lead bending.
(http://i1160.photobucket.com/albums/q485/jdansti/db48f1bb.jpg)
I experimented with the delay pot and decided to keep it off board in case I want easy access to a slappier sound. Thanks for sharing this with us!
Thanks Jdansti, glad you like it!
I have just finished designing the PCB for a simplified Equinox that is a drop in replacement for the Solstice (no fat switch), so eventually I will post that too. Much smaller PCB than the original Equinox.
Great job merlinb!!
i've one question... what do i have to do to make this pedal true bypass and use a 3pdt?
excuse my noob question :P
Quote from: lukatosh on May 25, 2012, 01:27:55 PM
i've one question... what do i have to do to make this pedal true bypass and use a 3pdt?
Like this, but without bothering with the DPDT tails switch (red). The green switch is the 3PDT, with the third pole being used for the LED switching on the PCB.
(http://i81.photobucket.com/albums/j207/merlinblencowe/Equinox%20Reverb/TrueTails.jpg)
Thanks Merlin!
Hi guys, are you ok? My Solstice doesn't modulate, when I switch on, the sound doesnt change, please help me, thanks a lot!!!
Quote from: newild on June 08, 2012, 06:38:35 PM
Hi guys, are you ok? My Solstice doesn't modulate, when I switch on, the sound doesnt change, please help me, thanks a lot!!!
I just ran into a similar problem I find that mine works for about 10 minutes and then it sounds 100% dry. The 78L05 reglulator becomes so hot that I can't touch it. If completely power it down and wait for about an hour, it works fine again for another 10 min.
Edit: BTW, welcome to the forum!!! :)
Quote from: Jdansti on July 08, 2012, 01:39:48 AM
I just ran into a similar problem I find that mine works for about 10 minutes and then it sounds 100% dry. The 78L05 reglulator becomes so hot that I can't touch it. If completely power it down and wait for about an hour, it works fine again for another 10 min.
the 78XX family has a 'thermal shutdown feature, if the device gets too hot it will try to protect itself by turning off the output. overheating is casued by excessive dissipation, so check the voltage across the regulator and current draw (perhaps open LK9 and insert your multimeter).
According to the data sheet, the PT2399 draws 30 to 40mA, so 2 of them draw 60 to 80mA from the regulator output (78L05 max = 100mA). If you are using a 9V regulated supply, the regulator will have (9V-5V)=4V across it, and will dissipate 240 to 320mW. the T0-92 device has a case-ambient thermal resistance of 200degC/W, so the temperature rise of the regulator chip will be 48-64 degrees C from ambient. At an ambient of 20C (68F) the regulator chip is at 68-84C - a bit warm, but still ok.
However - if your PT2399s both draw on the high side, and you use an unregulated supply (say 12V - not unusual for 9V wallwarts) we might see" 0.08A* (12-5V)=0.56W. 0.56W*200=112 degrees. At 20C ambient (junction temperature is now 132C) we are getting a lot closer to shutdown territory.
if everything is normal & works ok otherwise it might be worth replacing the L series regulator with a 7805, simply because the temperature rise will thoretically be only be 25% (case-ambient thermal resistance of 50degC/W).
david
Quote from: greaser_au on July 08, 2012, 07:22:05 AM
Quote from: Jdansti on July 08, 2012, 01:39:48 AM
I just ran into a similar problem I find that mine works for about 10 minutes and then it sounds 100% dry. The 78L05 reglulator becomes so hot that I can't touch it. If completely power it down and wait for about an hour, it works fine again for another 10 min.
the 78XX family has a 'thermal shutdown feature, if the device gets too hot it will try to protect itself by turning off the output. overheating is casued by excessive dissipation, so check the voltage across the regulator and current draw (perhaps open LK9 and insert your multimeter).
According to the data sheet, the PT2399 draws 30 to 40mA, so 2 of them draw 60 to 80mA from the regulator output (78L05 max = 100mA). If you are using a 9V regulated supply, the regulator will have (9V-5V)=4V across it, and will dissipate 240 to 320mW. the T0-92 device has a case-ambient thermal resistance of 200degC/W, so the temperature rise of the regulator chip will be 48-64 degrees C from ambient. At an ambient of 20C (68F) the regulator chip is at 68-84C - a bit warm, but still ok.
However - if your PT2399s both draw on the high side, and you use an unregulated supply (say 12V - not unusual for 9V wallwarts) we might see" 0.08A* (12-5V)=0.56W. 0.56W*200=112 degrees. At 20C ambient (junction temperature is now 132C) we are getting a lot closer to shutdown territory.
if everything is normal & works ok otherwise it might be worth replacing the L series regulator with a 7805, simply because the temperature rise will thoretically be only be 25% (case-ambient thermal resistance of 50degC/W).
david
David-
Thanks for the information about the regulators. I suspected the same, but I think I saw 5V on the output after the Solstice stopped working. I'm going to substitute a 7805 anyway and see what happens. If I understand you correctly, the temp rise on the TO-220 case should be small enough to not require a heat sink. Is this correct?
Quote from: Jdansti on July 08, 2012, 12:23:59 PM
David-
Thanks for the information about the regulators. I suspected the same, but I think I saw 5V on the output after the Solstice stopped working. I'm going to substitute a 7805 anyway and see what happens. If I understand you correctly, the temp rise on the TO-220 case should be small enough to not require a heat sink. Is this correct?
I'd say at regulated 9V you won't need heatsinking.
david
Quote from: greaser_au on July 09, 2012, 06:31:58 AM
Quote from: Jdansti on July 08, 2012, 12:23:59 PM
David-
Thanks for the information about the regulators. I suspected the same, but I think I saw 5V on the output after the Solstice stopped working. I'm going to substitute a 7805 anyway and see what happens. If I understand you correctly, the temp rise on the TO-220 case should be small enough to not require a heat sink. Is this correct?
I'd say at regulated 9V you won't need heatsinking.
david
Thanks!
Hi, I just wanted to let you know that I tried to make my own (smaller real estate) PCB following the schematic and realized that it is wrong: Fsb should be grounded and Fsc should be connected to R22 and R23. It would be nice to have another look at the schematic to check for other errors that could have slipped in!
Quote from: lpanagis on July 09, 2012, 03:27:39 PM
Hi, I just wanted to let you know that I tried to make my own (smaller real estate) PCB following the schematic and realized that it is wrong: Fsb should be grounded and Fsc should be connected to R22 and R23. It would be nice to have another look at the schematic to check for other errors that could have slipped in!
I noticed that too and forgot to mention it. After I corrected the switch wiring, it seemed to operate fine other than going 100% dry after about 10 minutes. I hope that switching to the larger 5v regulator will fix this.
This was actually the second reason I wanted to make my own PCB: I'll use an LM7805 instead of its little brother. It can easily handle 1A and with its tab I can mount it on the aluminum enclosure and hopefully it will be kept cool. The little 78L05 is a 0.1A device and in the enclosure where convection cooling is practically impossible it can shut down after a few minutes. If the PCB design allowed, epoxying the regulator to the enclosure would alleviate the problem a bit but if you gig with it and it gets hot, it would still shut down on you. I believe an LM7805, mounted to the enclosure is the way to go...
Quote from: Jdansti on July 08, 2012, 01:39:48 AMI just ran into a similar problem I find that mine works for about 10 minutes and then it sounds 100% dry. The 78L05 reglulator becomes so hot that I can't touch it. If completely power it down and wait for about an hour, it works fine again for another 10 min.
I don't know if you've sorted this yet, but I've had similar problems with PT2399's in the past. The hot regulator was caused by the PT2399 locking up, and a bigger regulator didn't help. I followed the advice from here: http://www.diystompboxes.com/smfforum/index.php?topic=93868.msg816797#msg816797 and haven't had any more trouble so far. Instead of a voltage divider, I just put a 1N400x between the output of the regulator and pin 1 of the PT2399, which dropped the voltage to ~4.3 V. Worked like a charm. I can't hear any difference in the result, but I used it for a delay, not a reverb, so YMMV.
I'm planning to breadboard this soon. The clips sound very nice and un-springy. Thanks, Merlin!
Small resurrection here... I built my Solstice a couple of weeks ago, but been away on business so unable to play much with it. Seems it's not working entirely as expected.
I'm getting reverb for sure. And the reverb changes as I move the pot and the trimmer. So I'm pretty certain both PTs are doing their job (no sign of overheating, latching up, etc.). But it's a bit on the quiet side. And the reverb is there whether it's switched on or not! So I tried taking the JFET out, expecting nothing but dry.
Reverb. ???
And it's a whole lot louder - nearer to the unity I was expecting. Trick #2: replaced the JFET with a jumper, expecting wet signal to be always on. Back to quiet reverb. Hmm...
So is it possible to get signal into the PTs via the RHS of the circuit, i.e. via P1? And is it possible to suck signal bigtime by letting it through on the LHS, i.e. R9, et al.?
I might have to resort to probing voltages. I'll need to be brave. The last time I did this, I managed to turn a sub-mini tube into a light-emitting triode. Briefly. ;D
In the meantime, any thoughts?
Quote from: bluebunny on April 20, 2013, 01:38:03 PM
And it's a whole lot louder - nearer to the unity I was expecting. Trick #2: replaced the JFET with a jumper, expecting wet signal to be always on. Back to quiet reverb. Hmm...
So is it possible to get signal into the PTs via the RHS of the circuit, i.e. via P1? And is it possible to suck signal bigtime by letting it through on the LHS, i.e. R9, et al.?
Does P1 still allow you to turn the reverb down to nothing, either with of without the JFET? Pretty sure you've just wired something up wrongly.
I love my Rub A Dub reverb from 1776 effects, but the belton brick isn't cheap (and I already killed one!)
Definitely got this and the Equinox on my build list, especially as I have just received a bunch of PT2399 chips!
Thanks for another great layout Merlin!
Quote from: merlinb on April 20, 2013, 07:15:06 PM
Does P1 still allow you to turn the reverb down to nothing, either with of without the JFET? Pretty sure you've just wired something up wrongly.
Yep, P1 varies the reverb amount as expected. It's just that the switch/JFET isn't having much effect - except attenuating the signal into the PTs when it's there. :-\
Will get out my fine-tooth comb...
Ah ha! She flies! :D
Thanks for asking the right question, Merlin!
Quote from: merlinb on April 20, 2013, 07:15:06 PM
. . . Pretty sure you've just wired something up wrongly.
I was working from my own perf design. I'd been over it time and time again and was convinced it was OK. (And indeed, it was.) The error came when this myopic tw@t translated the good design into a slightly flawed piece of board! I had a run of five pads where two were connected, then a gap, then three were connected:
(1)=(2) (3)=(4)=(5)Sadly, I misread my own layout and connected them all together:
(1)=(2)=(3)=(4)=(5) ::)
The short explained everything: low levels, reverb on always, ...
Anyway, all's well that ends well. Working perfectly now. Thanks for a neat design, Merlin, and thanks for the prod in the right direction.
Hello
I have bought all the parts for this build....and I am a total Noob at this ... Would like to know if anyone can help with a Vero board layout PLEASE .... I could go the Equinox route as well if that were available
Attila
erm... i think i've got this working properly. it's more delay-ish than i've expected, sounds very bathroom-like with the trimpot all the way down (well, its on an external pot). it has that kinda "pop" with the attack, the trademark of a really short delay time (less so on the neck pickup than with the bridge).
i understand the PT2399 has its limitations, but does that (probably unhelpful) description sound about right? lol. roughly, how did everyone else set their trimpot?
I replaced the trim pot with a regular one and called it a feature!
Quote from: Jdansti on August 27, 2013, 10:32:55 PM
I replaced the trim pot with a regular one and called it a feature!
that's totally what i was thinking! lol
i'm having problems with switching - further back in this thread it was mentioned that the switch wiring was wrong, ie. it should be ground to lug 2 and JFET etc. to lug 3, but this just shorts my power supply. i'm using a J201. it didn't switch at all in the original configuration (had to jumper it for testing), so i don't know what's up.
ah... see, what happened was a secret lab in an undisclosed desert location fired an experimental gamma ray device into my brain which caused me to forget that JFETs don't work like NPNs and therefore totally overlook the pinout. that's surely the only plausible explanation. surely.
... no shorting anymore, but also no switching. boo. and no LED - that only comes on if i wire the switch as per the schem, but if i do that, then the Off position shorts.
Edit: not working anymore even when jumpered, nevermind guys i don't wanna waste your time with my scatterbrainedness.
It's been a while, but I seem to recall a switching issue with mine. I think I went back to Merlin's build docs and wired it as shown in my notes on his images:
(http://i.pgu.me/Wk6WdO2f_original.png)
thanks, John - that seems to be how i had it, i'll go back to that if i get things going again. in my frustration i've just omitted the switch altogether for now. i fear i might've killed both PTs, despite my best efforts not to. it's the only explanation i can think of - haven't probed yet as it's late, but i get a buffered clean sound in both on & off states. *sigh*
got the reverb working again, plus a feedback pot, and i'm still having problems with switching. i've tried a few 2n5952s and a J201 (i'm aware the former may need to be hand-picked). here's something else i don't get, and i don't doubt it's a dumb question: if FSa is 9V+ and FSb is ground, it shorts the power supply. i must be overlooking something?
after looking at the Equinox schematic, i decided to try using an NPN instead, but first i replaced the 1n4148 with a 10K resistor (also as per the Equinox) and alas, it works when i hook up 9V to the Gate of the 2n5952. was that diode backwards? i'm guessing probably not as no-one mentioned it and i'm not that wise, but in any case it seems to work now. is this bad? will it give me AIDS or cause a thermonuclear war? i assume the diode was there for a good reason
Quote from: MrStab on August 30, 2013, 03:15:57 PM
if FSa is 9V+ and FSb is ground, it shorts the power supply. i must be overlooking something?
Hmm, I think I labelled the layout image wrong. FSb and FSc are labelled the wrong way- swap them over to match the schematic.
that's just it, though, Merlin - everyone's saying it's labelled wrong in the schematic, but upon removing that diode, it works as per the schematic!
for the record, replacing R14 with a pot is awesome - so much more flexibility. i used a 50k pot, but had to limit the minimum resistance to about 15k with a fixed resistor to stop runaway feedback.
Check the output voltage of your 78L05 during cut outs. Some of us have had problems and have gone to the bigger brother 7805. You won't need a heat sink if you do this mod.
Quote from: MrStab on August 30, 2013, 06:18:41 PM
that's just it, though, Merlin - everyone's saying it's labelled wrong in the schematic, but upon removing that diode, it works as per the schematic!
I don't know what you're doing wrong, but apart from FSb and FSc being labelled back to front, everything is correct. Nothing wrong with the diode.
there don't seem to be any cut-outs, John. although i have noticed you reported your problems after 10 mins of use, and i've only had one or two jams that long with it so i'll test more extensively. apart from a few annoying batches of lock-up chips, i've been lucky in so far as Little Angel & several Small Time Delay uses.
for all intents and purposes, this is the Equinox switching system with a JFET instead of a BC337. should it work? probably not. but it does! lol. tails and everything. if it ain't broke, right..? i'm just expecting some catastrophic consequence to doing this.
btw, talking of catastrophe: if anyone tries the R14 feedback pot mod, it seemed to necessitate a 100R resistor in series with the trimpot (just a regular pot in my case) else it catches fire (this was before i got my clandestine switch working). although that may not be the case after the feedback pot is limited to 15k min resistance. as i mentioned i still need to test all this for extended periods to make sure it's safe.
ah, not so great - when the amp's turned up loud, some of the verb bleeds through in the Off state. lame. i had it all boxed up and ready to give away, as well - totally didn't notice till i put it through the FX loop. might just true bypass it as i can't seem to work this switching out at all, dunno what i've done wrong. or i could try a NPN like the Equinox. unless anyone can think of a simple fix to kill the bleed? apart from that diode lol. maybe a diode across the Drain & Source of the JFET, with the cathode facing towards the reverb section? unless, ofc, it's bleeding from the mixing side.
Edit: diode across the JFET didn't work. absolutely 0 voltage is getting through to it in the bypassed state anyway, not even on the lowest setting of my multimeter - so i think the switching is okay, it must be coming from somewhere else. i've heard of this before on delay-type circuits, maybe i should look up fixes. it's not the pot i added either, as it's the same when you set the resistance to what R14 would've been. hmm. unsure how i'd go about diagnosing this one.
from the Equinox thread:
Quote from: psychedelicfish on August 24, 2013, 05:47:25 PM
I read somewhere (on this forum, I forget where) that it's actually better to connect the digital ground to the main circuit ground through a small choke, which filters out the nasty digital crap from your normal ground.
maybe grounding the PT2399 pins 3 & 4 is behind this? it's a crashing waves kinda sound, affected in various ways by all the pots, present in both on & bypassed states. or intuition tells me it could be buffer-side.
sorry for excessive posting!
(LAST) update: because i'm a true deviant, i used the spare lugs of my DPDT to ground the Reverb pot when bypassed. problem solved... possibly. none of the horrendous popping you usually associate with passing DC and audio through a switch. a kludge indeed.
^ Good idea! (I think ;)) like you said, if it works it works!
Quote from: MrStab on August 31, 2013, 05:43:52 PM
(LAST) update: because i'm a true deviant, i used the spare lugs of my DPDT to ground the Reverb pot when bypassed.
Doesn't that defeat the tails?
i didn't think to look for that actually, i just tested it and you're right - no tails. i mentioned this possibility to the friend im making it for, though - they seem fine with it & didn't expect tails to begin with. it's an unfortunate compromise, but i guess it's a way to retain buffered bypass. this thing's really growing on me, i don't really wanna give it away! weirdly, i find it more enjoyable as an "overt" kinda reverb than the spring tank on my gigging head. you may have out-done Marshall! lol
it's for a friend who's into "glitch" type stuff but is dabbling more with guitar lately. it was hard convincing them that the runaway feedback from a non-limited feedback pot really wasn't a good thing. it makes sense to label that "Room size", i think. maybe the trimpot-turned-regular pot could be "Reflections". potifying R14 made the guy go from not wanting it to really wanting it, & personally i can't recommend it enough - totally blew the unit open. i didn't leave room for a battery, as i'm guessing this thing uses at least 60mA which would make it impractical anyway. but i will give them a DC plug wired to a battery clip, because i'm just nice like that.
awesome work once again, Merlin! thanks for all the help guys. fingers crossed i won't be back with another disaster. lol
What are you guys using for the jfet? I don't think I've ever come across another pedal that calls for a J112, so I don't have any in my parts drawers. Would a J201 work?
from Merlin:
QuoteYou need a FET with a low Vgs(off) rating, not greater than -3V really, unless you're willing to hand-select some that happen to be better than the data sheet maximum.
from the J201 datasheet:
min Vgs(off): -0.3V
max Vgs(off): -1.5V
Well, the J201 didn't work, so I decided to try bypass it. I ran the input into the 10k resistor after the jfet (R9), and I only seem to be getting the wet signal as output. The voltage regulator gets pretty hot, but puts out a consistent 5V. With the pot dimed, it's much quieter than unity gain. It seems to act more like a volume control than controlling the amount of reverb, and I get no output when it's turned all the way down. I'm at work right now, but I'll post voltages when I get home. Does anyone have any ideas what could be wrong?
If you've removed the FET and injected your input just before R9, then all your signal is going into the PT2399s. You don't have a "dry route". Which is why it's wet. If you meant something else, then I'm talking b0ll0x... (Long day!) :icon_redface:
That would be it then. I actually clipped off the jfet leads and wrapped the input wire around what was left of the one that was soldered to R9, cause I was too lazy to unscrew the PCB to get under it. If put a J201 back in there, would it work or would there be a better spot to run the input into?
If you put the J201 back (and assuming it works), then wouldn't you put the input into the op-amp input buffer, as per the schematic? This buffer drives both the wet and dry routes.
Another Solstice board etched and ready to drill and populate. :)
I spread the non-polar cap pads out a little because I found on my first build that my box caps have a larger lead spacing than Merlin's cute little blue caps. ;)
(http://i1160.photobucket.com/albums/q485/jdansti/CD933F70-DC93-4DF0-9595-7B2DF87D68CF-2414-0000024EC1237BF5_zps870c0f06.jpg)
Onboard Solstice/Amp Application
I just wanted to share some information about using the Solstice as a onboard reverb for a practice amp. My application is a Murder One amp, but this would work with any other 9-12VDC amp such as a Smokey, Ruby, Noisy Cricket, etc.
The Murder One uses a 12VDC power supply, so I tapped the power from the amp's power switch to supply 12VDC to the Solstice. The op amp on the Solstice can handle more than 12V, and it sounds great at 12V. I'm using a 7805 regulator instead of the smaller 78L05, and it easily drops the voltage from 12 to 5V for the PT2399s without getting hot.
Since I'm not using the specified bypass switch for the Solstice, I simply jumpered the SPDT switch connections on the board. If I don't want reverb, I just turn P1 completely CCW and I get a clean signal. There's no need for a bypass switch when embedding the Solstice, and the main switch for the amp kills power to it when I switch the amp off.
I like to have P2 as an offboard pot instead of a trim pot, so the other thing I did was minimize the number of wires going to the offboard pots as shown in the drawing below. There's no need to run multiple ground wires to the pots.
Anyway, I hope this helps those who want to add reverb to their practice amps.
(http://i.pgu.me/Tbi+q+7Q_original.png)
So I can't find any jfet that gets this thing to switch. The voltage regular seems to read fine. I get clean signal through when wired up as per the schematic. Is there a way to measure a fet's Vgs(off) so I can go through my stock and find one that's in spec?
Well, since I see you've tried a J201, which should have worked but didn't, I suggest you check the rest of the wiring around the gate of the FET (unless your J201 was fake and way out of spec). You might, for instance, have the diode round the wrong way.
In terms of measuring VGSoff check the Fetzer Valve (http://www.runoffgroove.com/fetzervalve.html) article, there's a FET tester at the bottom which will give you the FET's VGSoff. Be aware that they call VGSoff "VP" in that article.
As a quick test, disconnect the switch and place a temporary jumper across FSa and FSc. This should switch the reverb on if all else is ok.
Well, I've actually got two Solstice PCBs that I built side by side. One is part of a multifx unit and I have FSa and FSc jumpered, with the input true bypassed. The other one is in its own enclosure and the LED works, but there's no reverb. I just put the Jfet tester together from the Fetzer Valve page, and I'm getting readings from .8 to 1.5 for various J201s. Is that supposed to be a negative value? My meter is reading positive with the leads set up as per the schematic.
VGSoff means the gate to source voltage where the device will be "off" if you go more negative, or "on" if you go more positive (in the case of JFETs). In the Fetzer Valve tester, you're measuring the source to ground voltage when the device is sitting on it's turn off voltage. So yes, your positive voltages are normal, and your JFETs are fine.
Check and double check your wiring around the JFET. The black strip on the diode should be pointing towards the 1M resistor and 10n capacitor. Make sure you have a 1M resistor in there. If the diode is right, try lowering the value of the resistor. I'm working on something on the breadboard ATM, and it uses JFET switching similar to this, but I'm using 10k rather than 1M, and everything works perfectly.
Make sure you have +5v on pin 1 of the PT2399.
Hi, I tried this build and it worked!
And I made my own layout in a different kind of way. I want to box it in a 1590a so I needed a two side PCB, but I only had one sided boards, had to try something new for me:
https://www.dropbox.com/s/ndkj9s9hg29pcvx/SolsticeAll.pdf?dl=0 (https://www.dropbox.com/s/ndkj9s9hg29pcvx/SolsticeAll.pdf?dl=0)
the CI's and some resistors are at the copper side,
later I post some pictures.
Thomas
Hi,
the pictures of my build:
(http://i1303.photobucket.com/albums/ag159/Thomas_Eduardt_Hafemann/DSC_0655_zps89c6814a.jpg)
(http://i1303.photobucket.com/albums/ag159/Thomas_Eduardt_Hafemann/DSC_0654_zpse6a5ed54.jpg)
It's working, and soon it will be enclosed in a 1590a box =D
Cheers,
thomas
This looks interesting, I have a few spare PT2399's left so I might give this a go. Does anyone have a video or sound clip? The dropbox mp3 link is dead now.
Congratulations on the 1590a pcb Thomas, looks neat. Have you tried double sided board?
Hi,
it's a single sided board, I just made a layout where I solder some components on the copper side to save some space.
A double sided would be much better I guess, but this was my first experiment.
Thomas
hello to all, Firstly thank you Merlin for posting such a nice build and everybody else for posting their experiences that they gained along their travels. This is my second pedal around PT2399(first was a cave dweller delay). I have rectified the fsc-fsb labelling error from my build after reading about it in the earlier discussions(I felt that the 9 volt battery was getting hot but didn't had the courage to discourse from the documentation ;D). My issue is that I am getting no reverb! clean sound on both the states of spdt I used. any suggestion? uploading photographs soon after registering on photobucket :P thank you
I had the same problem, and one pt was getting hot...
it happened sometimes when I connected the power jack. It was probably the latchup problem.
Check if the pt's are hot, if there is no effect at all it's probably the first one.
When I have the latchup problem i just unplug the 9v wait until the capacitors discharge and connect it again. It worked for me.
I really don't know what is the latchup problem with the pt2399, but it's pretty common with the little angel circuit too, but for a different reason.
Check the voltages at your pt2399, and signal paths.
Quote from: disto on January 16, 2015, 07:39:16 PM
This looks interesting, I have a few spare PT2399's left so I might give this a go. Does anyone have a video or sound clip? The dropbox mp3 link is dead now.
I recommend the Equinox II rather than the Solstice:
http://valvewizard.co.uk/equinox.html
QuoteI had the same problem, and one pt was getting hot...
it happened sometimes when I connected the power jack. It was probably the latchup problem.
Check if the pt's are hot, if there is no effect at all it's probably the first one.
When I have the latchup problem i just unplug the 9v wait until the capacitors discharge and connect it again. It worked for me.
Make sure pins 3 and 4 of the PT2399s are BOTH grounded. This was missing from my original Solstice circuit and does cause some PT2399 samples to latch up.
Quote from: thomasha on January 31, 2015, 08:25:58 PM
I had the same problem, and one pt was getting hot...
it happened sometimes when I connected the power jack. It was probably the latchup problem.
Check if the pt's are hot, if there is no effect at all it's probably the first one.
When I have the latchup problem i just unplug the 9v wait until the capacitors discharge and connect it again. It worked for me.
I really don't know what is the latchup problem with the pt2399, but it's pretty common with the little angel circuit too, but for a different reason.
Check the voltages at your pt2399, and signal paths.
going to short the 3 and 4 pin that may be the culprit..
going to short the 3 and 4 pin that may be the culprit.
in the mean time here is the Solstice :)... still needs some tweaking...
(http://i1117.photobucket.com/albums/k598/sanjaydubey/Image1392_zpssj46bx5c.jpg)