Braids THT in KOSMO format

Hi, I wanted to build a through-hole version of the braids in the KOSMO format!
Luckily I found this:
There are eagle files so I thought it will be easy to get going, but when I import them into kiCAD, there are some strange missing connections… I think there are vias for the ground planes, but I don’t really know.
Can anyone check?
The only things I would like to change are the jacksockets, so probably just remove them and replace with molex connectors. This way it can also be made smaller and so be cheaper on JLCPCB :wink: And maybe make some more space for the knobs… let’s see! First I need to know, what is up with the missing connections!


I would also like to build a KOSMO version of that, It was mentioned here recently:


I also want to have a kosmo format of that Braids. I’ve been looking at that for a couple of weeks now. I only waited because of Sam’s response. However, I was thinking the same thing. Remove the jack sockets and use molex connectors and reposition some of the pots for more room for the knobs. I am working on something similar with a Barton quantizer.

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Then let’s do that!! Tonight I will retry importing the stuff in kicad and see if I can understand the missing connections. It might be that it is some kind of ground plate stitching, I know too little about that stuff, but I will try!

What about a breakout board like the one on Sams LFO for in’s and outs? I think the open source idea like a Salt of what have you is a great idea.

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I’m not sure I understand what you mean… You mean an extra board for the jacksockets to avoid having to put wires on them? Good idea, but for now I will start with molex connectors, because I only have those sockets at home :wink:
For the rest of your post I am not sure if you are talking about the braids specifically or more on general open source modules? Of course it would be nice to have more of them in KOSMO format! But I want to start with the braids :slight_smile:

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When I brought up the idea of Braids Sam hinted toward OS module, then the through hole pcb for Braids was linked in the discussion. Someone had a file for 1/4" sockets for IKad so the idea of enlarging the pcb and swapping out components was a thought, or breakout board.

So, I got it imported in KiCAD

It is a bit weird, because there is no schematic connected to this, but you can edit it. So far, I have changed the sockets to molex connectors. The thing is: when you change a footprint, you sometimes have to reconnect the pads to the appropriate nets by rightclicking on the pads and then selecting the net.
Next, I want to make the board a little shorter in y direction (to get below 10cm for cheap JLCPCB) and wider in x direction (to have more room). So it should be a little under 10cm in each direction. Then move the pots and encoder and maybe the display around to use the additional space… This will be the annoying part.
Finally I want to replace the resistor footprints with slightly larger ones, so standard resistors fit. This resistor footprint change should also be done on the brain board, but apart from that, that one needs no adjustments, I think.

Feel free to join me!


I will look in my files, I thought I saw a schem. I like where you are heading, keep going!!!

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There is a schematic in the download of brain and controller together, but I have not managed to get that one connected to the pcb file. But I don’t think it is necessary, as long as we don’t want to change a lot in the connections / swap out parts completely.

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Yesterday I got a pack of STM32 (bluepill) in the mailbox but then I noticed that my FTDI cable is only 5V. So I had to order another programmer.
I already started looking for the other parts and I think I can get almost everything here in germany from Reichelt (conrad for the MCP4822-E/P). But so far I can not find the MCP3204-BI/P, only CI/P.
From the datasheet I assume that this means that the Integral Nonlinearity (INL) is ±2 LSB (MCP3204-C) instead of ±1 LSB (MCP3204-B). But what does that mean for the sound?? looking at @fredrik @Bitnik maybe?

Sidenote: I got 2-3 spare bluepills (have not yet checked if they are 128k), if anyone in Europe/Germany is interested.

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So from a quick peek at the schematics, the MCP3204 is used to handle the control voltages for V/OCT, FM, TIMBRE, and COLOR, all of which have a CV input range of 0-10 V (*). The ADC is 12-bit, i.e. 2¹²=4096 levels, so one bit corresponds to 10/4096 = 0.00244 V or (10/4096)/(1/1200) = ~3 cents. So ±2 LSB would be a swing of 12 cents, which may be audible (for V/OCT, at least).

If you’ve ordered one already, I’d suggest putting it in a socket and playing with it a bit, to see if you notice. You can get the BI/P from or for around ~3,50 € + S/H.

*) The main circuitry runs at 3.3 V but all four CV inputs use input stages that multiply the CV signal by 24.9k/100k (so 0-10 V is turned into 0-2.5V internally) and the ADC uses a 2.5 V reference, so it’s effectively a 10 V ADC.

EDIT: it’s an ADC, not a DAC :woman_facepalming:


You are a wizard!! Thank you! Yeah, I will probably get both versions and make some tests once I have the pcb ready.

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I’ve started to give some thought to the input-output problem for hybrid modular, and threads like this are very helpful. Essentially only a few different kinds of voltage scaling and amplication are needed. I can think of the following:

  • To and from 10V peak-to-peak with or without offset
  • To and from nominal 5V trigger level with optional inversion and programmable leading/trailing edge trigger.

These all appear to be simple op amp circuits that could even be wired into a connector cable. This would make building a hybrid module into something like assembling a model from Lego bricks. You could construct the connection cables in advance and reuse them again and again.

Most digital electronics units of the sort we’re using in hybrid follow the familiar use of header pins with 2.54mm spacing, and the same kind of connector pin could be soldered to the contacts of switches, pots, buttons and the like. This really would simplify prototyping.


I know it’s here in the US, but I did find it here on Mouser.

EDIT: Sorry, I didn’t see that @fredrik already posted a link

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Uh, I noticed that shipping is ~20€ for mouser and digikey. But I found it here:

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I can’t be of any help at all as it pertains to sorting out any electronic issues and/or making the module better. However, I am a graphic designer so if you want me to design a front panel for it when it is done then I can certainly help in that respect. Just let me know. I’m happy to do it and I’d like to help where I can.


Yeah, that’s a bit annoying if you only need a component or two. They both offer free shipping from 50€ though, so with enough planning and/or vague plans for future builds :slight_smile: you can get around it.

I’ve never used RS, and thought they were mostly UK but seems they’re all over the place. Do they offer free shipping on everything, even? (looks like they have minimum package sizes, though)

Phew, when I change the resistors to the larger ones, the whole layout is broken… I’m not sure if this was a good idea xD I will try now one at a time…

RS is ~6€ shipping in Germany, also free above 50€. With digikey and mouser there will be additional taxes, because it is send from outside of EU, I assume. Last time they were very quick! I ordered at 8 in the evening and the package arrived the next day at noon!

@popflier Frontpanel design would be awesome! But I can no guarantee that I have success with the board within the next few weeks… It would also be good to work out the placement of pots and display (and jacks) before finishing the pcb itself, because it has to match and I am quite bad at placement.

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This works a lot better!