Hi Everyone, my first post so hoping that this is in the right place. I am fairly new to building Kosmo format / DIY modular and have completed my first module. Tried the ADSR as it seemed like the easiest to get me going! I was wondering about building the Yu Synth Fixed Resonant Filter Bank Module but I realized these are all 15v. I was wondering t how easy/difficult or even possible it is to use 15v designs in my plans for a Kosmo Rack? I did have a scan across the forum and could not find a similar thread so apologies if I missed that. I would love to have a proper filter bank but am struggling to find anything that is DIY in 5U and 12v. Any assistant greatly appreciated and many apologies if this is really noob question.
Thanks
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Looks like you stepped up your ambition level in a hurry! Nothing wrong with that.
I’m prepared to be contradicted by those who understand this stuff better, but I’m betting the circuit would work just fine with ±12V. Sometimes you need to change some component values to get the right signal voltage levels or what have you, but here I think that’s not an issue. You could and probably should breadboard it and try it — I wouldn’t try to breadboard the whole thing, of course, but you could do the inputs, one output, and one filter frequency.
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Many thanks for the reply, I agree with you that it’s ambitious but it is more about planning what I want to include in the rack overall and it will be a module down the road a bit ! (erm…quite a bit tbh). Good to know that it should be ok, I will try your suggestion before I go full-on and buy the whole thing. I hope that Sam considers adding something similar to the FFB in his own brand of Kosmo modules.
Many Thanks again.
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You’ll get a bit more limited headroom, but that probably only matters for the low input (which has 2.5× gain) and is easy to attenuate away (*). Otherwise there’s nothing in that circuit that depends on the extra 3 V.
(*) or use a slightly larger R83.
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I’ve also been eyeing this design…it’s a doozie!
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I like when you start eyeing things 
.
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Some of the YuSynth boards, like the ARP VCF, actually have footprints for multiple power connection options including 2x5 Eurorack. Nothing in the text for that module addresses use of ±12V but presumably the connector’s there because it’ll work (and Eddy Bergmann has said it does).
The Minimoog VCF has modifications specified for ±12V.
And then there are boards, including the fixed filter bank, that do not have Eurorack header footprints. Those might work without modification or might not.
So doing Kosmo or Eurorack versions of the YuSynth modules depends on the module.
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More great stuff, and thanks again @analogoutput for looking further into this. I had emailed Yves from YuSynth a few days ago and he has just replied which I really wasn’t expecting as I had seen someone else say they did not receive a reply from him. I have added the reply below. Strangely though I could not find the specific BOM he was referring to on his page [here] so it may be elsewhere.(http://yusynth.net/Modular/EN/BANK/index.html) . Anyway, all good info that will hopefully be of interest to others and much thanks to Yves for taking the time to respond to my request.
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He’s quoting the MiniMoog filter page first, as an example of a circuit that does need modifications, and later states that the filter bank works as is. As we’ve already said in this thread 
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The BOM in question is at http://yusynth.net/Modular/EN/MOOGVCF/index.html.