# My Dual Diode Ladder VCF **URL:** \ **Category:** KOSMO MODULES\ **Created:** [May 4, 2025, 3:25pm UTC](https://lookmumnocomputer.discourse.group/t/my-dual-diode-ladder-vcf/7849 "2025-05-04T15:25:23Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![rodrigoDMH](https://yyz2.discourse-cdn.com/free1/user_avatar/lookmumnocomputer.discourse.group/rodrigodmh/32/30179_2.png) [@rodrigoDMH](https://lookmumnocomputer.discourse.group/u/rodrigoDMH)\ **Post date:** [May 4, 2025, 3:25pm UTC](https://lookmumnocomputer.discourse.group/t/my-dual-diode-ladder-vcf/7849/1 "2025-05-04T15:25:23Z")
Finally posting the end result of my VCF build! ![IMG20250405192514](https://global.discourse-cdn.com/free1/uploads/lookmumnocomputer/original/3X/0/a/0a5aaf0fb28b33dcb3fd09092f027ce606580935.jpeg) This is a Moritz Klein inspired dual VCF. Each filter has essentially two cutoff knobs: the smaller one on the side and the center one, which is a dual-gang potentiometer. This way I can bias each side’s cutoff frequency and control both at the same time with the big knob at the center. I also added voltage control to Drive and Resonance via internal diff-amp VCAs. There is a switch to link both filters to Filter A cutoff CV, and another switch that does the same to the Drive and Resonance CV. There’s also a cutoff CV input normalled to the V/Oct CV trace on the power bus. All Filter B input jacks are normalled to their Filter A equivalents, and all CV inputs have attenuverters (except for the V/Oct one, which can be attenuated to x0, x1/2 or x1/1 V/Oct wtih another switch on the front panel). I’m pretty happy with the sound, visuals and ergonomics. The KiCad project can be found here: [GitHub - DeMarco/DMH-Dual-VCF-Diode-Ladder-Mk2: Version 2 of my dual Diode Ladder VCF module](https://github.com/DeMarco/DMH-Dual-VCF-Diode-Ladder-Mk2) Here’s a demo and some more pictures: [![](https://global.discourse-cdn.com/free1/uploads/lookmumnocomputer/original/3X/a/a/aa693eaf2ba8a9e479b2aea2e84a455715b59c57.jpeg "My Diode Ladder VCF in action") ](https://www.youtube.com/watch?v=I2ttUE8nrj4) ![IMG20250405183458](https://global.discourse-cdn.com/free1/uploads/lookmumnocomputer/original/3X/3/3/337512ad14fc266291cbb8ccb16bdf5870f989fa.jpeg) ![IMG20250405183544](https://global.discourse-cdn.com/free1/uploads/lookmumnocomputer/original/3X/4/b/4b4ad84ad7c742f128d6cfa6b6175b295c09b025.jpeg) ![IMG20250405192727](https://global.discourse-cdn.com/free1/uploads/lookmumnocomputer/original/3X/c/6/c6305af28b5425e371df5b51eec01920e1f2cb29.jpeg) Next challenge: Dual Voltage Controlled Envelope Generator, so that I don’t need to use the one from my Moog Grandmother anymore 😛 ![image](https://global.discourse-cdn.com/free1/uploads/lookmumnocomputer/original/3X/5/8/58ca3819426565ca793145534bf838575a7fd500.png) ---
**Author:** ![EddyBergman](https://yyz2.discourse-cdn.com/free1/user_avatar/lookmumnocomputer.discourse.group/eddybergman/32/13513_2.png) [@EddyBergman](https://lookmumnocomputer.discourse.group/u/EddyBergman)\ **Post date:** [May 5, 2025, 7:53pm UTC](https://lookmumnocomputer.discourse.group/t/my-dual-diode-ladder-vcf/7849/2 "2025-05-05T19:53:56Z")
What a fantastic filter. Amazing work!! ---
**Author:** ![krztoff](https://yyz2.discourse-cdn.com/free1/user_avatar/lookmumnocomputer.discourse.group/krztoff/32/29609_2.png) [@krztoff](https://lookmumnocomputer.discourse.group/u/krztoff)\ **Post date:** [May 5, 2025, 9:57pm UTC](https://lookmumnocomputer.discourse.group/t/my-dual-diode-ladder-vcf/7849/3 "2025-05-05T21:57:21Z")
If you ended up with spare boards, PM me please 🙂 ---
**Author:** ![danbass](https://avatars.discourse-cdn.com/v4/letter/d/9e8a1a/32.png) [@danbass](https://lookmumnocomputer.discourse.group/u/danbass)\ **Post date:** [May 6, 2025, 12:23am UTC](https://lookmumnocomputer.discourse.group/t/my-dual-diode-ladder-vcf/7849/4 "2025-05-06T00:23:47Z")
I too would love one! ---
**Author:** ![Kelaifu](https://avatars.discourse-cdn.com/v4/letter/k/46a35a/32.png) [@Kelaifu](https://lookmumnocomputer.discourse.group/u/Kelaifu)\ **Post date:** [May 6, 2025, 10:16am UTC](https://lookmumnocomputer.discourse.group/t/my-dual-diode-ladder-vcf/7849/5 "2025-05-06T10:16:27Z")
saw this on GH a while ago and was very interested, glad to see it got finished. What a beauty! ---
**Author:** ![analogoutput](https://yyz2.discourse-cdn.com/free1/user_avatar/lookmumnocomputer.discourse.group/analogoutput/32/29663_2.png) [@analogoutput](https://lookmumnocomputer.discourse.group/u/analogoutput)\ **Post date:** [May 6, 2025, 11:24am UTC](https://lookmumnocomputer.discourse.group/t/my-dual-diode-ladder-vcf/7849/6 "2025-05-06T11:24:28Z")
“GH”? ![tiny](https://global.discourse-cdn.com/free1/uploads/lookmumnocomputer/original/3X/c/1/c13e64addcf8ab426631ece0eb23ad24911418ca.png) ---
**Author:** ![Kelaifu](https://avatars.discourse-cdn.com/v4/letter/k/46a35a/32.png) [@Kelaifu](https://lookmumnocomputer.discourse.group/u/Kelaifu)\ **Post date:** [May 6, 2025, 1:17pm UTC](https://lookmumnocomputer.discourse.group/t/my-dual-diode-ladder-vcf/7849/7 "2025-05-06T13:17:57Z")
it’s the hub of git yo ---
**Author:** ![rodrigoDMH](https://yyz2.discourse-cdn.com/free1/user_avatar/lookmumnocomputer.discourse.group/rodrigodmh/32/30179_2.png) [@rodrigoDMH](https://lookmumnocomputer.discourse.group/u/rodrigoDMH)\ **Post date:** [March 27, 2026, 11:26am UTC](https://lookmumnocomputer.discourse.group/t/my-dual-diode-ladder-vcf/7849/8 "2026-03-27T11:26:15Z")
@danbass , @krztoff and anyone else building this, beware of a change I made after my first build, which I think is not present in the original Gerbers: you should use C-tapered pots for Resonance control. Linear B-tapered pots produce almost no effect between 7 and 12 o’clock and make the usable range a bit finicky to play with. ![image](https://global.discourse-cdn.com/free1/uploads/lookmumnocomputer/original/3X/6/3/6321786239c69f5bcc2cba83a1c35c6003fc22eb.png) Here’s the one I used: [https://www.taydaelectronics.com/potentiometer-variable-resistors/rotary-potentiometer/anti-log-reverse/c100k-ohm-anti-log-taper-potentiometer-knurled-plastic-spline-shaft-pcb-9mm.html](https://www.taydaelectronics.com/potentiometer-variable-resistors/rotary-potentiometer/anti-log-reverse/c100k-ohm-anti-log-taper-potentiometer-knurled-plastic-spline-shaft-pcb-9mm.html) A more elegant solution (to make it less dependent on specialty pots) would be to design an exponential VCA to control the resonance, but I’ll leave that to a (far-)future Mark 3 version 😛 .