# PolyKit 16 Polysynth **URL:** \ **Category:** DIY STUFF\ **Created:** [January 13, 2023, 2:54pm UTC](https://lookmumnocomputer.discourse.group/t/polykit-16-polysynth/5842 "2023-01-13T14:54:50Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![craigyb](https://yyz2.discourse-cdn.com/free1/user_avatar/lookmumnocomputer.discourse.group/craigyb/32/21602_2.png) [@craigyb](https://lookmumnocomputer.discourse.group/u/craigyb)\ **Post date:** [January 13, 2023, 2:54pm UTC](https://lookmumnocomputer.discourse.group/t/polykit-16-polysynth/5842/1 "2023-01-13T14:54:50Z")
Just started a new Polysynth based on the PolyKit DCO, it will be 16 voice, bi-timbral and mounted in a 3U rack, programmable upper and lower sounds or a split or whole mode. Very similar to the PolyKit DUO 6 voice I made earlier but with a few more options on the front panel. ![322967608_1518769211936793_3729407420237017046_n](https://global.discourse-cdn.com/free1/uploads/lookmumnocomputer/original/3X/a/c/ac13f58c18df260f8139e396a59702a8d60d1164.jpeg) ![20230113_110707](https://global.discourse-cdn.com/free1/uploads/lookmumnocomputer/original/3X/9/f/9ffa9d011585229aeff16fd732d738e0774dc60d.jpeg) ![20230113_140404](https://global.discourse-cdn.com/free1/uploads/lookmumnocomputer/original/3X/0/0/005dbb9aab4c90839fcd670fe297c924e9953751.jpeg) ![20230113_140341](https://global.discourse-cdn.com/free1/uploads/lookmumnocomputer/original/3X/2/f/2f0df202388b48993b8e814655b54a21e035551e.jpeg) > Blockquote ---
**Author:** ![savt22](https://avatars.discourse-cdn.com/v4/letter/s/ad7895/32.png) [@savt22](https://lookmumnocomputer.discourse.group/u/savt22)\ **Post date:** [January 13, 2023, 4:31pm UTC](https://lookmumnocomputer.discourse.group/t/polykit-16-polysynth/5842/2 "2023-01-13T16:31:22Z")
Looks amazing. Out of interest how are you doing the key tracking for the filter? ---
**Author:** ![craigyb](https://yyz2.discourse-cdn.com/free1/user_avatar/lookmumnocomputer.discourse.group/craigyb/32/21602_2.png) [@craigyb](https://lookmumnocomputer.discourse.group/u/craigyb)\ **Post date:** [January 13, 2023, 4:32pm UTC](https://lookmumnocomputer.discourse.group/t/polykit-16-polysynth/5842/3 "2023-01-13T16:32:38Z")
I run a second Pico driving two 8 channel DACs for keytrack and velocity ---
**Author:** ![twinturbo](https://avatars.discourse-cdn.com/v4/letter/t/8baadc/32.png) [@twinturbo](https://lookmumnocomputer.discourse.group/u/twinturbo)\ **Post date:** [January 14, 2023, 7:47am UTC](https://lookmumnocomputer.discourse.group/t/polykit-16-polysynth/5842/4 "2023-01-14T07:47:58Z")
Dam, I havent even started the 6DCO yet 😉 … I am off work the week after next and re-desiging the DCO to a Kosmo rack is my goal… Good work!! Rob ---
**Author:** ![craigyb](https://yyz2.discourse-cdn.com/free1/user_avatar/lookmumnocomputer.discourse.group/craigyb/32/21602_2.png) [@craigyb](https://lookmumnocomputer.discourse.group/u/craigyb)\ **Post date:** [January 14, 2023, 7:51am UTC](https://lookmumnocomputer.discourse.group/t/polykit-16-polysynth/5842/5 "2023-01-14T07:51:39Z")
Thanks, no idea if this project will even work, but I can back it down to a dual 6 voice if necessary. I built a modular version of the DCO using a Seeed XIAO RP2040 and just made it dual oscillator. Added level controls, FM, PWM etc all in one module. ![20221117_202951](https://global.discourse-cdn.com/free1/uploads/lookmumnocomputer/original/3X/2/7/27959361e152bf674aa207c12f2493ef6d11b1f6.jpeg) ---
**Author:** ![craigyb](https://yyz2.discourse-cdn.com/free1/user_avatar/lookmumnocomputer.discourse.group/craigyb/32/21602_2.png) [@craigyb](https://lookmumnocomputer.discourse.group/u/craigyb)\ **Post date:** [January 15, 2023, 2:33pm UTC](https://lookmumnocomputer.discourse.group/t/polykit-16-polysynth/5842/6 "2023-01-15T14:33:21Z")
Front panel completed and ready for connection to a demux board to generate some CVs. ![20230115_155958](https://global.discourse-cdn.com/free1/uploads/lookmumnocomputer/original/3X/6/c/6cbebc586e95a49cdab9f910358ba0f6906a6f69.jpeg) ![20230115_155945](https://global.discourse-cdn.com/free1/uploads/lookmumnocomputer/original/3X/2/1/2152f5ac3260f96faae5dc3ad74602de8b29009d.jpeg) ---
**Author:** ![MarkWestbroek](https://yyz2.discourse-cdn.com/free1/user_avatar/lookmumnocomputer.discourse.group/markwestbroek/32/12476_2.png) [@MarkWestbroek](https://lookmumnocomputer.discourse.group/u/MarkWestbroek)\ **Post date:** [January 18, 2023, 10:41pm UTC](https://lookmumnocomputer.discourse.group/t/polykit-16-polysynth/5842/7 "2023-01-18T22:41:58Z")
hi, So after the DCO’s you’ll have 12 analog VCF’s and 12 analog VCA’s? Or is the whole synth digital? ---
**Author:** ![craigyb](https://yyz2.discourse-cdn.com/free1/user_avatar/lookmumnocomputer.discourse.group/craigyb/32/21602_2.png) [@craigyb](https://lookmumnocomputer.discourse.group/u/craigyb)\ **Post date:** [January 19, 2023, 7:46am UTC](https://lookmumnocomputer.discourse.group/t/polykit-16-polysynth/5842/8 "2023-01-19T07:46:30Z")
After the DCO will be 16 VCF and 16 VCA and 32 EGs and 4 LFOs and 2 noise sources. ---
**Author:** ![twinturbo](https://avatars.discourse-cdn.com/v4/letter/t/8baadc/32.png) [@twinturbo](https://lookmumnocomputer.discourse.group/u/twinturbo)\ **Post date:** [January 19, 2023, 12:31pm UTC](https://lookmumnocomputer.discourse.group/t/polykit-16-polysynth/5842/9 "2023-01-19T12:31:26Z")
Sounds awesome , be interesting to see. ---
**Author:** ![craigyb](https://yyz2.discourse-cdn.com/free1/user_avatar/lookmumnocomputer.discourse.group/craigyb/32/21602_2.png) [@craigyb](https://lookmumnocomputer.discourse.group/u/craigyb)\ **Post date:** [January 19, 2023, 3:29pm UTC](https://lookmumnocomputer.discourse.group/t/polykit-16-polysynth/5842/10 "2023-01-19T15:29:23Z")
Full of flu all week so no real progress, but before it kicked in I’d done a quick redesign. Rotated the display through 90 Deg to give a better layout and relocated a few of the buttons. Also swapped out the 4051 mux chips for 4067, I couldn’t get the pot readings stable with the 4051 so swapping them for 4067 seems to have resolved that issue.just enough room between the pots to squeeze them in. ![20230119_172531](https://global.discourse-cdn.com/free1/uploads/lookmumnocomputer/original/3X/1/f/1fea66cf3eb94e876d48e4e4f8a3f1a33abba3f2.jpeg) ---
**Author:** ![antoine.pasde2](https://yyz2.discourse-cdn.com/free1/user_avatar/lookmumnocomputer.discourse.group/antoine.pasde2/32/326_2.png) [@antoine.pasde2](https://lookmumnocomputer.discourse.group/u/antoine.pasde2)\ **Post date:** [January 20, 2023, 3:34am UTC](https://lookmumnocomputer.discourse.group/t/polykit-16-polysynth/5842/11 "2023-01-20T03:34:06Z")
> [@craigyb](#): > > Rotated the display through 90 Deg to give a better layout and relocated a few of the buttons. The buttons look much better under the display than they did beside it. ---
**Author:** ![Soundbrigade](https://avatars.discourse-cdn.com/v4/letter/s/4af34b/32.png) [@Soundbrigade](https://lookmumnocomputer.discourse.group/u/Soundbrigade)\ **Post date:** [January 20, 2023, 2:50pm UTC](https://lookmumnocomputer.discourse.group/t/polykit-16-polysynth/5842/12 "2023-01-20T14:50:37Z")
STOP IT!! STOP IT!! STOP IT!! STOP IT!! STOP IT!! STOP IT!! STOP IT!! I am struggling with my unfinished modules and haven’t even started to think about how to power them … IMPRESSING project and hopefully there will be no kit or PCB to buy. However I am interested in the huge board - where did you get that (and please to don’t tell me). ---
**Author:** ![craigyb](https://yyz2.discourse-cdn.com/free1/user_avatar/lookmumnocomputer.discourse.group/craigyb/32/21602_2.png) [@craigyb](https://lookmumnocomputer.discourse.group/u/craigyb)\ **Post date:** [January 20, 2023, 3:32pm UTC](https://lookmumnocomputer.discourse.group/t/polykit-16-polysynth/5842/13 "2023-01-20T15:32:32Z")
Thankyou very much, I have had to stop this week, absolutely full of flu and trying to figure out why the mux was making random reads occasionally. I can’t really think straight but now I’ve realized very stupidly that these green LEDs are power hungry little buggers and can kill a USB powered input to the Teensy, voltage drop was almost 0.3v when testing. So I fitted a seperate LM317T regulator to maintain a seperate 3.3v supply to the 74HC595s and this seems to have resolved the issue. Its been a terrible week of flu, power outages, loss of heating, air raid sirens, random fuse trips in the house etc. Glad its sort of over and my flu is clearing up. Large boards are available from AliExpress ---
**Author:** ![craigyb](https://yyz2.discourse-cdn.com/free1/user_avatar/lookmumnocomputer.discourse.group/craigyb/32/21602_2.png) [@craigyb](https://lookmumnocomputer.discourse.group/u/craigyb)\ **Post date:** [January 23, 2023, 6:48pm UTC](https://lookmumnocomputer.discourse.group/t/polykit-16-polysynth/5842/14 "2023-01-23T18:48:23Z")
Some further progress now my health has improved slightly. I built a mother board to hold a total of 12 daughter cards. The first card being a 40 channel CV DEMUX and 32 shift register outputs. Added onto that card are the LFOs for FM, TM and PWM and their respective control VCAs. Then there’s just enough room to squeeze in the noise source. This daughter card will be replicated halfway down the motherboard to provide the same for the lower 8 voices. So far so good, all working as expected. ![20230123_204253](https://global.discourse-cdn.com/free1/uploads/lookmumnocomputer/original/3X/5/f/5fa602a68e25e2634888b0fa8834f193f73e421c.jpeg) ![20230123_204247](https://global.discourse-cdn.com/free1/uploads/lookmumnocomputer/original/3X/8/4/840b6b5bb4c7fe7e5368f2b5b8cfcb14075191a6.jpeg) ![20230123_195308](https://global.discourse-cdn.com/free1/uploads/lookmumnocomputer/original/3X/9/f/9f12be2afb010a83eafb1f91b22488f4781d55c9.jpeg) ![20230123_171157](https://global.discourse-cdn.com/free1/uploads/lookmumnocomputer/original/3X/b/4/b4a2c19c6f2a21a7e2e7a57c40de49343c1bec88.jpeg) ![20230123_171128](https://global.discourse-cdn.com/free1/uploads/lookmumnocomputer/original/3X/e/c/ec8f6b6fd7679175beefe0b48a0fb25e51649ff8.jpeg) ---
**Author:** ![Bpbby](https://yyz2.discourse-cdn.com/free1/user_avatar/lookmumnocomputer.discourse.group/bpbby/32/15259_2.png) [@Bpbby](https://lookmumnocomputer.discourse.group/u/Bpbby)\ **Post date:** [January 23, 2023, 8:14pm UTC](https://lookmumnocomputer.discourse.group/t/polykit-16-polysynth/5842/15 "2023-01-23T20:14:45Z")
As always it looks amazing ! It is funny how your work looks satisfying for me, nearly relaxing. ---
**Author:** ![craigyb](https://yyz2.discourse-cdn.com/free1/user_avatar/lookmumnocomputer.discourse.group/craigyb/32/21602_2.png) [@craigyb](https://lookmumnocomputer.discourse.group/u/craigyb)\ **Post date:** [January 25, 2023, 2:08pm UTC](https://lookmumnocomputer.discourse.group/t/polykit-16-polysynth/5842/16 "2023-01-25T14:08:26Z")
A 16 DCO voice board sandwich. ![20230125_160724](https://global.discourse-cdn.com/free1/uploads/lookmumnocomputer/original/3X/4/e/4e79204b10d9423bfa24abcfeb0018200f6c88a9.jpeg) ---
**Author:** ![savt22](https://avatars.discourse-cdn.com/v4/letter/s/ad7895/32.png) [@savt22](https://lookmumnocomputer.discourse.group/u/savt22)\ **Post date:** [January 25, 2023, 6:00pm UTC](https://lookmumnocomputer.discourse.group/t/polykit-16-polysynth/5842/17 "2023-01-25T18:00:51Z")
Do you use those female stacking header strips often? I had a couple of problems in my latest build that I traced back to loose connections with them. Was just wondering if you’d had the same experience or if I was unlucky? ---
**Author:** ![craigyb](https://yyz2.discourse-cdn.com/free1/user_avatar/lookmumnocomputer.discourse.group/craigyb/32/21602_2.png) [@craigyb](https://lookmumnocomputer.discourse.group/u/craigyb)\ **Post date:** [January 25, 2023, 6:04pm UTC](https://lookmumnocomputer.discourse.group/t/polykit-16-polysynth/5842/18 "2023-01-25T18:04:35Z")
I’ve used them on a few with no problems. ---
**Author:** ![craigyb](https://yyz2.discourse-cdn.com/free1/user_avatar/lookmumnocomputer.discourse.group/craigyb/32/21602_2.png) [@craigyb](https://lookmumnocomputer.discourse.group/u/craigyb)\ **Post date:** [January 26, 2023, 6:07pm UTC](https://lookmumnocomputer.discourse.group/t/polykit-16-polysynth/5842/19 "2023-01-26T18:07:43Z")
First voice card taking shape, same as before with dual multi-pole filters, dual ADSR, but I’ve moved the mixer VCAs to this board and added wave shaping for triangle and a sub oscillator with VCAs for these too. Running out of parts fast. ![20230126_164155](https://global.discourse-cdn.com/free1/uploads/lookmumnocomputer/original/3X/f/0/f0999887b69f99b1b91803d2cf373c210e6f4f8f.jpeg) ---
**Author:** ![twinturbo](https://avatars.discourse-cdn.com/v4/letter/t/8baadc/32.png) [@twinturbo](https://lookmumnocomputer.discourse.group/u/twinturbo)\ **Post date:** [February 1, 2023, 7:27am UTC](https://lookmumnocomputer.discourse.group/t/polykit-16-polysynth/5842/20 "2023-02-01T07:27:47Z")
Impressive progress. is it a one off or are you going to PCB it? I expect the BOM will be quite a bit? Rob [Next page](https://lookmumnocomputer.discourse.group/t/polykit-16-polysynth/5842.md?page=2)