PT2399 DELAY simple 'after chorus'' mod...

[deadastronaut]

hi guys, happy new year to all....

been tinkering with a standard pt2399 delay on breadboard just for fun again.....poking and tweaking here and there, as you do..

and found a great little easy peasey mod for ''after chorus''  (chorus on the delays)

adding a 1M from pin 6 to pin 8 on the pt2399 creates a warble, but just enough to chorus the delayed signal..

heres a clip ...first without the 1M, then with the 1M.

just thought it was interesting enough to share...a nice easy mod for any pt2399 delay...which we probably all have..

add a switch to it, for optional spaceyness...

https://www.dropbox.com/s/ikyz8lnfq4jgnzr/pt2399chorusmod1.wav?dl=0

it can get pretty crazy as you change values to lower ones...so if you like totally warped noise stuff make it a pot



i hooked up a meter to the 1M (pin6/8) and without playing it sits at around 1.65v 

when playing it dives down to around .20v then creeps steadily up to the idle at  1.65v again...

which creates the warble as it is connected to the delay time pin 6. so why not use it...

anyway have fun. rob. 

[merlinb]

Ooh nice discovery!

[iainpunk]

just thought it was interesting enough to share...a nice easy mod for any pt2399 delay...which we probably all have..

no, i don't

despite that, nice idea, if i ever choose to build a delay (despite hating the effect), ill put such a warble mod in!

cheers

[deadastronaut]

A man who hates delay....

Thats a first for me....i love delays n verbs...spacey man. 

[Ben N]

Really cool, Rob. I've got one PT2399 delay boxed up, three in the works. Gotta give this a go. Cheers!

[Ripthorn]

Awesome, Rob! I'm going to play with this with some of the upcoming projects I've been planning. Just might be the ticket for something I'm spec'ing out right now!

[jhergonz]

sounds great.

[deadastronaut]

yeah give it a go guys, i put lfo's on my delays for the chorusy effect,

but i was looking at how to wobble it without all the extra circuitry...it works.

if you have a ready made pt2399 delay just tack a 1M on pin 6-8

let me know if its not just a fluke..

[Mark Hammer]

Lovely.  Instant Andy Summers!

Thanks so much for that.  I need to see if there's room for another toggle on mine.

[Ripthorn]

I usually use separate LFO's as well, but sometimes I do stuff that is very space constrained, so this seems like a great thing to try. I also want to play with bypassing the 1M resistor with a cap to see if there is any additional weirdness that can happen! Too bad I have to wait until I'm home from work to get the breadboards out...

[iainpunk]

A man who hates delay....

Thats a first for me....i love delays n verbs...spacey man. 

ow, reverb is totally fine because it is continuous, not instantaneous. i really don't know why i cant stand playing with a delay on, i just dont like the feel and response. only really short slapback is acceptable when im playing blues.

another idea: envelope dependent impedance between those pins, instead of the 1M resistor. i guess a Jfet would do the job if the right one or several ones in series are used and the amplitude of the envelope isn't too big.

cheers

[deadastronaut]

Yeah i hear ya....with blues etc..

Mind you a slow delay just buried withn the reverb level is quite nice for slow bluesy stuff.....anyway ...


Yes the "wobble" is kind of envelope detecting already, as it sits at 1.65v when idle, then goes to around .20v

When actually playing /hitting..thrn recovers to 1.65v again...but i get ya, it could be explored further, but im cheap and lazy..and like

To keep it simple, just like me

[deadastronaut]

update, brian/ripthorn hit on it...nice one. 

use a 470n and 820k in series from pin 6 to 8.

without the cap the long repeats got a bit stuttery....

with the cap, nice long repeats and lush chorus...sorted.

have fun. 

[Ripthorn]

Nice! Thanks for saving me the effort . I started soldering up a development board for this last night (and to allow for some other investigations for a new project), but wasn't able to finish. So I will use this as a starting point, for sure! I think a three way SPDT toggle could be cool, to give a very subtle flavor, a more extreme flavor, and nothing.

As a side note, I had an ES56033-based delay on breadboard already and tried this trick. It doesn't work for that chip, but I am not surprised. You can't get delay time modulation with it like you can with a PT2399 due to what I believe to be internal compensation between the two Fadj pins (pins 2 and 3). Oh well, it was worth a try, and now we know...And knowing is half the battle.

[Mark Hammer]

Just finished trying out the mod, but didn't see your note about the series cap until now.  I would get the modulation for a moment, and then it would disappear.  Conceivably, the added cap will block a presumed DC from getting in the way.  Off to the green grocer now, and will try it when I get back.

[deadastronaut]

grab me an apple 

weird how it disappeared...its been on my breadboard for 3 days now and works no probs,

but yeah add the cap...


edit::: a clip with 470n-100k in series....like a spacegun ducking effect..

then back to 820k chorusy...so yeah on a switch...options.  ( i tried using a 1m pot but it was better just as presets)

https://www.dropbox.com/s/e54eg0cleqzb7jf/100kto820kdelaymod.wav?dl=0

[Ripthorn]

Sounds cool! How does it respond with distorted tones? I would assume still nice. I'm totally designing this in to at least one of my upcoming projects

[deadastronaut]

Havent tried with dirts yet....will do. 

[Mark Hammer]

grab me an apple 

I actually did and would gladly send it to you, but I'm not so sure it would be all that edible by the time it reaches you. 

weird how it disappeared...its been on my breadboard for 3 days now and works no probs,

I guess it may be one of those depends-on-which-batch-o'-chips things.

but yeah add the cap...


edit::: a clip with 470n-100k in series....like a spacegun ducking effect..

then back to 820k chorusy...so yeah on a switch...options.  ( i tried using a 1m pot but it was better just as presets)

https://www.dropbox.com/s/e54eg0cleqzb7jf/100kto820kdelaymod.wav?dl=0

So, I just added the cap to a 1M pot, so as to dial in the sound.  I didn't really get the chorussing until I dropped the resistance to 500k  Sounds really nice, so thanks.  But may require individually tailoring the pedal, rather than 470n/820k as a "boilerplate" solution.

[deadastronaut]

Cheers for the apple...

Yeah i figured it may be a batch dependent thing, glad you tried it..nice one.

And glad it wasnt a fluke...try the 100k space gun, ducking one too...