Fun with PT2399 delay regen path.....

[frequencycentral]

I just built a PT2399 delay with a BM tonestack in the regen path, tweaked for flat response in the middle, bass boost one end, treble boost the other. It sounds great - repeats can get progressively darker or progressively tinnier. Love it. Anyway, it's got me thinking - what else can we stick in the regen path to progressively...................the repeats? Octaves maybe......other stuff? Any other ideas? Maybe I'll experiment with adding a buffered effects loop......

[Earthscum]

hehe... I've done stuff in the regen path on accident. I tried an active clipper section. It sounded kinda neat, every repeat would become more distorted and closer to a "failing transistor radio" sound. I used a BMP clipper stage, ironically. Maybe we should just try an entire BMP in there, lol. Seriously, that could be something useable by bassists... Clean, no delay sound, with this repeated crap happening in the background.

The BMP stage got me thinking about trying an octave up in regen, but I've never got around to it... so there's an idea for you.

[CynicalMan]

I've been working on a design for an add-on feedback loop for delays. That would serve the same function as this, except it would be a separate box. I was planning on having treble cut, bass cut, and distortion to simulate an analog delay, as well as an effect loop. If you threw another delay in the loop, you could probaly get some neat reverb-ish sounds.

[SISKO]

This idea has come to my mind lately http://www.youtube.com/watch?v=Un0IjtVShB4 min 2.50
I could not try it yet. I have a Digitech whammy so im willing to know how those glitchy octaves comes out!

[cloudscapes]

I built a delay that progressively ringmods the repeats 
it sounded pretty nuts!

[teej212]

where exactly is the regen path? they dont give much info on the datasheet.  is it coming from pin 14?

[cloudscapes]

where exactly is the regen path? they dont give much info on the datasheet.  is it coming from pin 14?

it's the feedback path. where delay output feeds back into the input at variable amounts. stick fun stuff in-between!

[~arph]

A phaser.. the DL4 has this sweep echo mode, sounds like there is a phaser in the regen path.

[Mark Hammer]

The A/DA analog harmonizer pedal, would use the delay regeneration path to create "bell tree" type effects, such that each iteration was shifted up or down a specific interval.

[soggybag]

Effects loop in the regen path. Put any effect you like there.

[Earthscum]

Effects loop in the regen path. Put any effect you like there.

I was kinda thinking that and read through the comments. I was thinking you could easily do a 'datasheet' delay with a send from the delay output, and a return back to the input, and even add in an input mixing or tone section. Then you could, exactly as stated, stick anything in you wanted... even have  a whole delayed and repeated side chain.

On a side note, Rick...  I DID take an octave up circuit ran out of the delay, but not repeated. I was hoping that I could simulate a guitar accompaniment. I haven't gone back and tried it, but I think the Little Angel could make it work properly. It sounded like just a delayed distortion, dry... dull. I was thinking that maybe if you come to something close in your feedback experimenting but it's lacking, try a little warble and see if it livens things up.

[defaced]

A second PT2399?  Could this be a way to get longer delay times cleanly?  I'm thinking set the first up for a single repeat, then send that to the input of the second, then use that output and the original dry signal for the final sound.   

[cpm]

A second PT2399?  Could this be a way to get longer delay times cleanly?  I'm thinking set the first up for a single repeat, then send that to the input of the second, then use that output and the original dry signal for the final sound.   

thats how you do it, put them in series
but each stage adds to the background noise and quantization artifacts
and last, you need a way to synchronize the delay time on each chip. Think of current mirrors, vcr's, etc

[ThunderShowers]

Hmmmm, external Regen fx loop sounds like a gooood idea. Put another Delay in the regen path, see what happens.

In all seriousness, I'd prolly just stick a Valve Castor variant/Linear tube Boost in there, maybe the WMD Geiger Counter... Random Number Generator maybe?

Man, i have far to many Idea for this.

Flanger. Dear god, yessssssss.

[frequencycentral]

BTW, here's the little layout I used, fits nicely on the tabs of the tone pot:




The configuration of the tonestack is just about flat at mid position with a 6dB drop. At either end it cuts bass or treble. I'm still deciding if I want to recover gain with a little booster, or if I'll get it back by tinkering with the regen path resistor/pot. Here's some graphs too:

[egasimus]

So you just connect this to the wiper of the regen/feedback pot? How does it interact with various settings of the pot? Since:

connecting it to the wiper might not work properly at low feedback levels.

[frequencycentral]

I removed  the resistor right after pin 14 of the PT2399 (10k in the delay design I'm using), and replaced it with the tonestack.

[egasimus]

So, on the Rebote 2.5, that's the 24k resistor off pin 14? Or the 2k7 one?

[frequencycentral]

The 2k7 one. Or you could replace the 15k which is orange on the schematic.....that's probably what I'd do.

[egasimus]

Thanks a ton