YuSynth Fixed Filter Bank

When planning Kosmodrome, I decided to include a fixed filter bank (FFB). Back in the 1960s and 1970s, pretty much all Moog modulars had an FFB, either the 907 module or its successor the 914. These days, not too surprisingly, Behringer makes one, in Eurorack format, based on the Moog 914. Doepfer has a Eurorack […]

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Out with it

Well, finally. An output module. It takes four inputs, attenuates them, pans them (manually) in the stereo field, and has a stereo pair of line outputs and a stereo headphone jack. This thing has been such a pain in the ass for such a long time. Design changes, mechanical design stupidities, PCB layout errors, parts […]

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VCF, grounded

Last May Day I wrote: I don’t think the VCF is working as intended, though. It’s definitely not working the way I expect. I thought it was better when I built it but right now, no. It does do some sort of low pass filtering, the filter cutoff changes with the knob, and the resonance […]

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Precision ADSR, enhanced

I took the Kassutronics Precision ADSR design I breadboarded, with modifications, and designed a PCB for it. This week I built one. To refresh your memory, the Kassutronic design improves on the YuSynth ADSR (version 2) (and similar designs like René Schmitz’s Fastest Envelope In the West) by Curing the very slow release once it […]

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Absolute power

I have enough modules in Kosmodrome to warrant adding a second power supply and bus board — or at least a second bus board, I haven’t yet checked what fraction of capacity the power supply is running, but I figured I’d just go ahead and build a new supply. Or two, actually, because I’d like […]

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Easy, right?

I’m here to tell you that if you have a sudden desire for a simple AR envelope generator, you can build one quickly and easily. Or you can do what I did. Kosmodrome now has most of the basics, but it lacks an envelope generator. I have an ADSR planned. Planned is quite distinct from […]

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Almost LFO

I changed the PW and PWM CV pots on the MFOS VC LFO from 100k to 25k, the fixed resistors on the PW pot from 100k to 22k, and the mixing resistors from 10k to 200k. Everything seems to work and changing the PWM attenuator (with no CV plugged in) doesn’t change the pulse width […]

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Super sub

A while back Carmelo Azzarello posted a design for a sub oscillator, then later a revised version. He did it on stripboard as an auxiliary device to use with his Behringer Crave, but I decided to draw up a PCB for a synth module version. A sub oscillator is a device that takes an audio […]

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My latest PCBs from PCBWay arrived earlier this week. I assembled one today and, well, I almost got the design right. Back in prehistory, on March 11, I wrote: I’m actually breadboarding another controller, also based around an Arduino and a DAC chip, and it’s occurred to me I could probably design a PC board […]

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