Here is a very interesting and not overly complicated PT2399 based circuit from Bluff Chill Devices. It is an "envelope modulated delay" which sort of emulates a worn out tape delay.
This layout is for V1 only but there is two layouts; one for stock 2 knob version and one modified 4 knob version. See details for the latter further down of this post
First up the schematic and a writeup about possible mods at the Bluff Chill blog.
And the modified version with added Mix and Realese controls. Note that pot values and lug connections isn't mentioned in the blog post so some tweaking is necessary to get satisfying results. I added the values that "should" work...
*Edit* Jordan verified the modified layout bellow and tested pot values and tapers.
Later versions also had a feedback control and an improved blend circuit but there is no schematic avaiable for it on the web...
These look like a super interest build!!! will have to give it go tonight (likely the second version)
ReplyDeleteI noticed in the original pedal there is a sound reactive Led that lights up as you play - is there a way that can be implemented in this layout?
ReplyDeleteYes you can. By looking at the guts, the red LED on the board is moved to the front panel.
DeleteSecond (modded) layout is verified! I was able to answer my own question above and found that the LED was already sound reactive.
ReplyDelete100k lin works for flutter. tracking should also be linear - 20-25k is a good range (maybe even 50k if you really wanna push it but at a certain point the delays sound a bit too fuzzy).
Mix should also be linear, I used a 50k which works fine but 20k would probably be better.
Release control is very subtle and i can't quite hear it but the LED indicates its doing something - I use 250kLog which worked just fine - will test it with a linear pot when i restock.
Seems like a clean clari(not) type deal but without the LDR - I'd be interested in knowing if there is a way to add a feedback pot to this
Cool. I'll tag it and add the tapers to the pot values. Thanks for verifying!
DeleteWould love to know how to add a feedback control as well...
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ReplyDeleteJust build the four knob version with the suggested pots, sounds pretty good. The effect goes from subtle to pretty crazy. I even love the hiss you get in the background, sounds like worn down tape.
ReplyDeleteGreat layout
I added a feedback switch to my Chasm Reverb/Deep Blue Delay combo, and it works great. When I get home, I'll check how i did it and let you all know...it should work equally well with this build.
ReplyDeleteOK - the layout I used for the Chasm Reverb already had an oscillation option built in...maybe someone with better skills than myself can apply the method to the Shagpile. Here:
ReplyDeletehttps://tinyurl.com/t8wayx7u
Another option is the "Howl of Flaming Death" feedback mod as seen here:
https://tinyurl.com/2jbwty5j
I've had random luck with this one, but builds with the PT2399 chip respond very well in my experience!
I just tried the second mod mentioned - adding a 100k pot between the circuit out and circuit in changes this from a quirky filter, to an outrageously beautiful tape delay!
ReplyDelete