Wave folder

[@BadChizzle]

I enjoyed this video very much. The idea of folding things has always been I fun one for me. Maybe we could develop a VCA folder or something. You know... something never folded before. Orrrr... a fold folder?! I need a folder for my folder ideas. I like when the wave becomes an octave by folding magic! Rectified wave omelet chicanery. Let’s make an envelope to put our folders in, so we know just what our folding hath wrought. Thank you for the Cool video!

[@Electronic_hobby]

This is just great! Do you have a schematics for this?

[@Electronic_hobby]

Great job! I wonder what chips did you use?

[@organfairy]

LM324 but many other general purpose operational amplifiers can be used instead.

[@Electronic_hobby]

@@organfairy Thanks! I'll try to put it together.

[@TheLunaLockhart]

I've been searching for a wave folder to incorporate into my synth signal path, and this is one that doesn't require me to get 20 bloody op-amps like the Buchla 259 schematic I found, though I can't really read the resistor values very well on your drawing. Would you be so kind as to help me out?

[@organfairy]

On the picture "This is the actual wave folder" at 4:00 everything is 18k except the one under the word "compress" which is 10k. On the picture "This is the input circuitry" at 4:10 they are from left 10k potentiometer (other values can work too) 18k and 100k. The ones connected to the 220uF capacitor are 3.9k and 3.3k. On the circuit "CV in" they are from left 5.6k - 4.7k potentiometer - 10k - 18k. Under where it says "Offset" it is 1k - 3.3k - 2.2k. The two on the opamp at the far right are both 18k. The one at the output is 1k but that one isn't really necessary. It is there to limit the current if the output is shorted or connected to another output.

[@TheLunaLockhart]

@@organfairy wow, quick response! and thank you! I'm building an open-source Analog Synth w/ Full Logic Control (aka, complicated arduino programming and DACs) and I'll be adding your name to the credits most likely

[@DonMeadows]

Fold, Distort, Rave, Repeat.

[@AnalogDude_]

Hi, cool stuff. what is function of the 4th op amp and the switch above? Do you need to repeat op amp 1,2,3 after op amp 4? You can't read the resistor values.

[@AnalogDude_]

I see, why is the pull down resistor after op amp 3 before the compresor ... and what is the effect of the compressor?

[@organfairy]

The function of opamp 4 is to act as a kind of compressor - actually it is more like a soft-clipper but that a question of how you define it. The reason I put it in there is because when you fold the waves you will also make the amplitude or volume lower because the waves are folded "inwards". So it is an attempt to make a more steady volume. A side effect is that it introduces some distortion that colours the sound. I switch the compressor on at 5:17.I think it sounds best if the circuit is repeated but it can work with just the 4 opamps. In the demo I first use it with only opamp 1 and 3. Then at 4:53 I switch to all 4 opamps and then at 5:05 to both circuits.

[@organfairy]

There is a pull-down resistor on the input of opamp 3 because the two diodes can only push up so you need a resistor to pull down. There is a pull-up resistor on the input of opamp 4 because the diodes there can only pull down.

[@AnalogDude_]

organfairy right. thank you. Pretty cool thing you built there from scratch and explained well.

[@AnalogDude_]

organfairy so if you built this circuit, you should place this compressor at the end?

[@erbro]

The wasp wires look really mean :-D

[@organfairy]

"The mean wasp wire wave folder".......... maybe that could be the name for this design ........ or at least a good test if the police wants to find out if a driver is under influence....

[@AdamTheAd-vanc3d]

Wow this looks great and admire your ability to explain it better than me . I did a video on a wave folder circuit. If you dont mind ill put a link to your video on my vid.

[@organfairy]

That's OK by me.

[@KiR_3d]

OrganFairy, i was made an MS-20 filter clone without 5-7 and 10-12 pin jumpers on LM13700... And i've got a kind of waveshaper/distortion. It gives a rough sounding signal... I've decided to use it for a solo. You can listen it here: soundcloud.com/kirill-threedee/ms-20-clone-test There are two oscillators that goes to one filter. So this phasing is because of it.

[@KiR_3d]

Awesine (oops! :) ) Awesome explanation! Now i clearly see the leafs on your oscilloscope in 3d! Explaning things with paper + sticks (and etc.) constructions is a great technique. You remind me my pal from Domodedovo (the suburban of Moscow). He lives with his cats and does everything for his house. Also he works with orders to assembly PSU parts and different synth. things for musicians. P.S. the music in the beginning is cool! It's so chilling. Not everybody writes in this style. For ex. my head creates something "paranoic" like this very often: soundcloud.com/kirill-threedee/lost-in-woods instead of chill music

[@organfairy]

I have occationally tried to make sequencer based music kzbin.info/www/bejne/p2etppmvbZ6DptE . But it's like....... my brain wants to make melodies for some strange reason. So I have mostly used sequencers as something running in the background.

[@KiR_3d]

Please, master your music skills as much as you can. And swim by your style :) I "hear" such track in movie series about almost anything. "Weeds", "Fargo" and even "Breaking Bad" could have soundtracks like this. If you'll find a good manager, maybe you'll become a new Van Gelis (in your area/style). After years i regret that for some time i've changed the direction and dived into gfx/2d/3d... Music was moved deep into a background. Now my friends (from that scene) are pretty known musicians, they play over the globe...