Rebote 2.5 delay with tails and modulation (another epic journey thread)

[samhay]

The delay pot is currently only talking to PT4 - is that the plan or are you still playing with the current mirror?

[deadastronaut]

really, no thats not the plan....that's weird as i'm definately getting longer delay as it is?

may have to try that current mirror again then..

edit: yep, tried the current mirror, original version, works better now, still the issue of fast being slow...but slows are much better/cleaner now.

[deadastronaut]

latest clip with current mirroring..

using just 1M pot for fast, then a 1M resistor in series with the 1M pot for slow...

https://dl.dropboxusercontent.com/u/7464107/delaymirror.mp3

[deadastronaut]

: i couldn't get that diode/cap/resistor part to work on the ''current mirror, as soon as i attached it between any pt there was no delay...hmmm..

seems to work fine without it anyway...its started up everyday with no problems at all..

one thing that's bugging me now though, my lfo is not being stable now when connected to the delay pot.....hmmm its working, but pretty random wobbliness now and then.

ive tried connecting the lfo to the current mirror emitters..works but random too.


a nice thing i tried earlier was jumping the pt's and getting a long single delay then multiple delays on the repeats  with different timings depending on which pt was jumped.......pretty cool....


now to get that lfo sorted..

[psychedelicfish]

now to get that lfo sorted..

Have you tried modulating pin 2 (Vref) like in the little angel and one chip chorus? Another thing you might try is modulating the supply voltage. The PT2399 is rated for 6.5V, so you've got a bit of room to shift things, but you'd probably have to make a discrete voltage regulator.

[deadastronaut]

hi ed, good idea.

yep, the lfo on pin 2 works for sure...however, only at short-ish delays, (probably why it was used for chorus)

on long delays the lfo disappears entirely........hmmm...

[deadastronaut]

in the workshop (bench in my living room ) .......with a whiskey or two.....hic...

this is pretty much where i am...still lots of tinkering to do....but you get the idea..

[bluebunny]

Nice one, Rob.  Sounds great.  Looks like I'll *have* to build this one too.  <sigh>

BTW, cool graphics at the end.  I think this is no coincidence:

   

[deadastronaut]

you must build it by law...

anyway, a little problem i just noticed, on my crapocaster the single coils in the ''delayed signal'' are fine ...very clean.

however  my bridge humbucker (which is louder) makes the ''delayed signal''  distort ....hmmmm...the initial input is fine, its just the delayed that's nasty..any ideas..remediies?.


edit: nevermind, sorted it...


is there a simple way to get an led to light with repeats btw?..

[samhay]

Sounds good - what other magic do you have in the signal chain?

^is there a simple way to get an led to light with repeats btw?..
Do you want a tempo indicator? If so, it can be done, but when I built it I had problems with the tick bleading through.
http://www.diystompboxes.com/smfforum/index.php?topic=96054.0

Edit - actually, that won't quite work as it will give you 1/4 time (or 1/3 if you have 3PT2399s etc). I guess we need to add another divide by four.

[deadastronaut]

nothing in the signal chain...just delay  (there is a bit of reverb from the mixer only at the end of the vid though )

re led:  yeah i saw that a while back, too big for this beast though,.....i was just curious about a simple led on repeats...(just for kicks and a box etch idea i had really)

no matter if it can't be done though...

cured the distortion, and made the signal much cleaner too...


the lfo is still being a pita...it was fine hooking it up to the delay pot before i put the current mirror in, but now its pretty random wherever i put it..

the usual case of cure one thing, and it presents another problem...

[samhay]

I wasn't watchig properly ealier - nice volume swells at ~5min. It was the 'effect' at 7 min I was curious about though.

You can put a tempo LED on the LFO without any bother. I guess you could also use an envelope detector on the wet signal to drive an LED and give you some sense of the delay time when you are playing. I think you might have thought a little about sound-to-light circuits in the past?

[deadastronaut]

lol, yeah good ol 386 sound to light , but i found something smaller..

i was just looking at this ( TIP31) circuit..people run them on their stereo's ( i just ordered a couple of ttip31' to play with )

pretty cool, and responsive too...links are in vid description...

https://www.youtube.com/watch?v=OnSVr4eIFS8

thoughts?..

btw i was just tinkering about and got quite a good but basic reverb out of this too...

[samhay]

The input impedance of the BJT might load down the signal a bit.

[deadastronaut]

Hmmm...i,m guessing this wouldn't work with any bjt then...

[deadastronaut]

right today my mission is to get this @#$%ing  lfo sorted...

just been having issues with the lfo with short v's long delays...fine on short, but an ass on long stuff.

into the fray...

[deadastronaut]

 had a tinker about and this seems ideal...not too warbly...nice chorus, and nice fast shimmer too..

and doesn't mess around with randomness...seems ok so far. and definately not extreme and pitchy, and un-musical..



i'll test it a little more, power down, an power up, and make sure she's stable.....

getting there slowly..


i put 560r's on all the current mirror emitters, and she behaves well...

: its a shame really as i tried with much lower emitter resistors and it had a really  nice reverb that i played with for an hour or so, but as soon as it was powered down (had some dinner and came back)

it had locked up...but nevermind, i wasn't on a reproducing a belton brick quest anyway...

edit: the nice thing about this lfo is that the chorus i was after will be pretty much with both pots in the 12'0clock position too..bonus.

https://dl.dropboxusercontent.com/u/7464107/modtest1.wma

[deadastronaut]

well i know i'm talking to myself....but.

i just drew up and printed up 5 pages of schematics for this @#$%er...

now to make a layout.. ....i'll be using ceramics mostly to save space as there is a LOT of 100n's with the 4  PT's...

bye for now.......enjoy xmas.

[samhay]

Good luck. Hope you've been good and asked Santa for a really big enclosure.

Your LFO schematic looks interesting. I recognise the LFO, but the buffer/LED driver looks a bit funky with the series LED and R8 to ground. Will have to put that on my to-breadboard list.

[deadastronaut]

Hi Sam, well in hoping to 1590bb it 

yeah the lfo now has 2 leds in para, and tweaked..just less agressive, more smooth really...

i have 5 a4 sheets with colour coded match points on them...arghhhhhhhh, 

my head hurts...