My build progress

I used 12 gauge for mine, which was a bit tricky. I picked up some 14 gauge a while back to use for the next case. I may need to track down the file for those orange covers you have. I would prefer to print a pair of those to use than use the strips of tape I put over the screw heads.

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Hey, thanks for this, it is actually working. I tried again and found out I had the multiplier not exactly on zero (ground). It is 100% working !!!

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Ah! I got those covers here. You might be able to ask them for the files.

What’s the definition of insanity again…? Something, something, trying the same thing over and over expecting different results…? Tried laying out the oddness filter of the WSG breadboard differently after reading:

While recently building some WSG units I found that it is important to keep the three wires that control the filter cut-off frequency and resonance (RES1, COF1 and COF2) away from all the other wires that carry high level rectangle wave signals. This is because these three wires (RES1, COF1 and COF2) are part of the high gain filter circuit and are susceptible to having adjacent wires capacitively couple signals into them.

I thought maybe that’s what was causing all the humming, but no.

Everything seems fine, right up to the simple R10/C1 high pass filter just after that small orange jumper wire next to the cluster of 1M resistors. After that, putting a finger near anything close to the filter chip, causes a noticeable increase in hum volume. As does touching the outside of the POT casings, which is what’s leading me to think that something isn’t grounded properly.

I tried removing the resonance POT and just having the two cut off POTs on their own, but they did nothing. I also tried that the other way round with just the resonance POT connected on its own and it did nothing too. I think the only thing I didn’t try was a different chip, or replacing the +/-ve hook up leads.

I also tried sticking the multimeter on various bits to see what the voltage, or resistance was, and ended up having to stick the A10k volume control POT in so as to lower the noises. I suppose the only thing left is to try and follow Ray’s troubleshooting steps, but they don’t seem to talk about a humming.

I’ve obviously done something wrong, and it’s most likely to be something super simple. After starting at my breadboard, two different schematics, the PCB layout, the strip-board layout, and reading various results from Google searches, I have no idea what it might be though.

I’m about a fag paper away from giving up. So I’m going to throw it in a corner and forget about it for a few days, while I fill out a spreadsheet of bike bits to attach to a frame I came into possession of the other day. :disappointed:

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Maybe try grounding the pot casings? If they cause humming then could be worth a shot…

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It did cross my mind to solder a bit of wire to the bodies and then plug the other end into the breadboard. Some of the other POTs aren’t connected to ground though, so it’s got to be something else… :person_shrugging:

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wondering why this bypass switch doesn’t work? I lose cv completely when I bypass the glide circuit. do i need to insert at pin 5 of the opamp?

U15A’s non inverting input is still tied to ground, so both op amps put out 0 V, and at pin 7 that either conflicts with kbdCV or dominates it depending on whether the latter has a series resistor or not. So yes, simplest solution is to send kbdCV to pin 5. The cap will still soften the edges but presumably not by much. Other option is a DPDT to disconnect pin 7 when bypassing.

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Or you could try switching the cap C53 in or out and always have the key CV go through the two op amps.

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Yeah that should work… I just noticed R136 is in the bypassed part, so your input impedance presumably changes when you switch. If you don’t use @jaradical’s idea it should move to the other side of the switch.

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My prototype is finished :smile: appreciate all the help!

And remind me to never do an oscillator again

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This is looking really good!

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It’s like the CAKE module we never had…

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Yeah i had no idea it would be hard for a community to settle on a module =) haha!
all i knew was that i wanted a bitcrusher bit to it =D

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Will you ever HAVE to tho?

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This is 1/2 of a standalone (patching optional) mono synth project, not gonna be Kosmo, well at least I don’t think so unless it works out that way.

Wouldn’t be hard to do the oscillator bank in Kosmo. Youd give up some flexibility vs having 3 distinct oscillators with all the jacks but it would be nice having everything right there

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image

Simple 2.5cm mult is done and works :slight_smile: I will put up gerbers on GitHub soon if anyone is interested.

For the hihat I only managed to solder half of the resistors, there are so many and I need to sleep :sleeping: and I noticed already that I am missing some capacitors and a 10k A pot :-/

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I’ve been working on the panel for Euclid-O-Matic, which is my take on a euclidean sequencer. I cut the panel with a K40 laser from some wood and put the ring of LEDs behind a ā€˜window’ cut from transparent acrylic. It needs some work on the software side so … no demo yet.

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Finished two new modules, a Moog Ladder and a Buffered Multiple 4x3. I need to add a dual ADSR or AD/AR and at least 2 VCAs. I hope I can also manage to squeeze in safety valve :see_no_evil:

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Just finished up this dual VCA. This was my first stripboard layout, need to make a few fixes before making a graphic.

I’m not 100% sure what the reasoning was behind this, but one half of the VCA is Electric Druid’s Vintage LM13700 VCA and the other half is Ray Wilson’s Logarithmic/Linear VCA. In the end, I’m pretty happy I did it like this, they both have their own perks and quirks.

I guess part of the reason is in the name I gave it for fun. It’s called Top Results VCA because the two VCAs here are the Top Results on Google when searching for LM13700 VCA :rofl:

Now I have to tend to a few ā€˜Black Pill’ STM32 boards which I’m not entirely sure if they work.


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