Yes, s/Kassutronics/Barton/.
The Barton JFET Phaser is indeed two boards stacked. It’s mostly an all pass filter with a JFET, a capacitor, an op amp, and five resistors… and then repeat that eleven more times.
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Nice and clean work 
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Mmutant and FM just finish .only I need Connect 3.3v light to button ride side
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Heres Sams super simple mixer w/ gain control.
Big ups to the local wizard here pointing this out, this models a killer utility to have corralling percussion and boosting the stragglers. I simply replaced the 100K feedback resistor with a 1M pot. I hope somebody finds this as useful as i did. I mean who gets stoked over a mixer rite? 
This is sams super simple mixer w/ gain x10
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I need to build one of these myself. The only mixer I have in my case is a crappy stereo one that is useless for CV.
After a couple months with only 3 VCOs, one Buffered Mult and an adapter module, I finally could use my xmas holiday to build 3 more modules: S&H + Noise, a Mixer and a utilities module with attenuverters and a switched mult. 
Now that I have oscillators, noise and a mixer in place, I can move on to the filter project, which is gonna be a real challenge… Want to cram a dual version of Moritz Klein’s Diode Ladder design in a 30cm pannel, plus add CV to the Resonance control (which basically means adding two VCA circuits just for that), plus add attenuverters to the CV amount knobs. That should be fun.
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It’s been 6+ months since I’ve checked in, and I still don’t have everything in the case as I’d like it, but I hit a meaningful moment the first time I racked the AO Wave Displacer and started finding surprising tones that were previously out of reach.
I’m still in full on exploratory phase now, but I’m set up with a case with midi support. Unfortunately, I have two AO ADSRs, audio mixers, a ringer, VCLFO, and nearly a dozen other functional models I worry that my case is already constrained trying to host 2 or 3 voices, let alone all the percussion. (Or all the PCBs in the queue)
I so appreciate this community and each of your contributions. Hope to give back as well over the next year.
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Nice rig!
I see my most played boardgame too!
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Do you mean the Electric Druid design using the VCDO1 PIC, or the Frequency Central VCDO1-based Klang Stadt? The main oscillator has a selection of 16 waveforms, not 32, and should morph between waveforms if the control voltage changes a bit, rather than dither.
Or are you having problems with the sub-oscillator dithering, because that has CV selectable sub-octaves.?
Yes I understand, but even 16 waves on a pot is not easy to navigate, all I was saying is changing to multiturn for the wave and sub wave selects helped enormously in making wave selection easier.
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My interest is that I am building some Klang Stadts, (when I get round to replacing the pots I foolishly damaged in an ultrasonic cleaning bath).
Perhaps precision resistors and a 16-way rotary switch would work, but they are incredibly expensive, and would not allow the intermediate morphed waveforms.
Maybe a centre detent on the Waveform pot could work, in conjunction with a precision voltage fed into the Waveform CV input when a precise or repeatable waveform is wanted. The Klang Stadt PCBs don’t accomodate multiturn pots.
Or maybe separate Coarse and Fine controls for Waveform control voltages.
I note the the VCDO1 circuit design has 100n capacitors on all the control inputs. Maybe larger, good quality capacitors might help.
I wonder how frequently the PIC samples the input control voltage, and if any hysteresis is designed in. EDIT: looking at the code, I think it’s 32KHz and No.
The VCDCO is extremely unstable on input voltages, there are a few mods in place to stop it jumping around.
I actually built a polysynth with them and used 12 under micro processor control for waves, note CV etc. it was to be honest a bit of a nightmare. Eventually I updated the firmware for a custom version that helped and actually moved the more usable waves from the sub to the main waveform.
It has some minor pin changes because of the mods and the different use of pins and also included a sync option.
I have the firmware around somewhere and link to the pages for it.
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That looks cool. Any more details?
When looking for a diffuser for a led-display, try and find a broken LCD-tv in your local skip. Immediately behind the glass layer there are a few thin layers of plastic sheets that are in fact lenses one of which is ‘milky white’ which makes a great diffuser for LEDs (in fact, these sheets are there to diffuse the light from the LED back lights of the tv). Cut them to size with a pair of scissors or a laser cutter and place them in front of your display. I’ve used them for neopixel displays and the results are really nice.
This picture shows a dial to the right where I used the diffuser material on top of a ring of neopixel LEDs. Unfortunately because of the high sensitivity of my phone’s camera the picture looks a little blurry and it does not do justice to the effect. In reality it looks much better.
Btw does your spectrum show the low frequencies on the right and the high frequencies on the left of the display?
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2399 Splashback delay done and ready for exploration
T’was a laissez-faire constitution en masse.
added the wet mod no prob thanks to the gang here(standing on the shoulders of giants)
Yeah this sucker gets purty wayout mang, particularly when it’s fed CV.
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I’m afraid you’re going to need to provide proof
It’s the time of year where I make a lot of build progress, though not synth related. Here’s a unit which fires off up to 16 confetti poppers controlled via DMX. It works by charging up some supercaps, then dumping that charge to melt a piece of resistor wire holding a small tank of compressed gas together. As added challenge the whole thing should be IP65, so I really had to do concurrent design of the pcb and enclosure.
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This is the part where someone here comes up with a way to turn it into a synth anyway.
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I mean it’s basically a 1-minute-attack, 200-ms-decay, instant-release envelope generator…
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