Eric's Kosmo synth build

I’ll document my built in this thread.

I have first build my MikroKosmos modules :

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This week-end was again a 25mm week-end…


As I am missing the LM358s, CD4013, B1M pots, and some caps, only the LFO is finished and working right now.
The others have been powered up too and the voltages at the IC sockets are all right, promising :slight_smile:

The Attenuverter and Attenuator will have to wait until the Mouser order with the faders comes in.

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Ok, did not post anything here for a long time…
That doesn’t mean I didn’t build.

After running out of some components, I built this this week-end :


It will be used on the workbench. One day I’ll build a real case (procrastinating again :stuck_out_tongue: )
Still missing a batten between the two “legs”, to strengthten it and support the PSU and busboard.
This will need another trip to the store…

Annnnd…


The modules already mounted are confirmed working.

  • a simple voltage generator to test the other modules (top button from 0V to +8V, middle button from -8V to +8V, pushbutton 0-5V)
  • MikroKosmos “CS” (“Control Surface”, designed to be mounted in an horizontal case)
  • k25 LFO
  • k25 Attenuverter
  • k25 Attenuator (used to reduce the signal to what the cheap bluetooth speaker’s line-in can handle)

The others :

  • #1222 VCO: works, but isn’t calibrated yet, and the display isn’t mounted as I’m still trying to get it flush with the panel (which is slightly warped, anyone had that problem ?) (The octave switch is not mounted right now because of the display, but works).
  • #1181 VCA: not tested.
  • #1161 Multiple: a fast test seems to indicate it works, needs confirmation.
  • #1114 Grrrr: not tested.
  • #1157 ADSR: a fast test seems to indicate it works, needs confirmation.
  • #1145 VCLFO: a fast test seems to indicate it works, needs confirmation.
  • #1113 Filter : out of jacks…
  • 2x Seq Switch: missing push buttons of the right size, one has tact-switches to test it, seems to work.
  • k25 A/R EG: missing the pots.
  • k25 Dual G2T: a fast test seems to indicate it works, needs confirmation.
  • k25 Sub-Osc: a fast test seems to indicate it works, needs confirmation.
  • k25 Glide: not tested.
  • Dual Quantizer: Out of 1N5817 (and botched the arduino socket :slight_smile: )
  • 4x MikroKosmos: missing the pots.

Not shown:

  • a second k25 A/R EG (missing the pots).
  • a second #1222 VCO, not started yet.
  • a KosmicTaxidermist not started yet (the special ICs are somewhere between China and France, I hope they are genuine ones…)

Planned:

  • no seriously, there isn’t enough space here :slight_smile:
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Oh, snap! Look at that! No wonder you’ve been silent, you’ve been busy!

Love the happy cow mats too btw.

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Nice work! Gonna be a badass rig!

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I had a slightly warped panel with the ADSR module, but after I mounted the jacks it was OK.

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whouaou ! a lot of modules, soon another case :slight_smile:

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Soon a first case… well, when weather permits to work outdoors… doesn’t look like it this week…
This is just a frame for the workbench to avoid having powered modules lying among cut-off resistors leads :slight_smile:

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looking good! "to avoid having powered modules lying among cut-off resistors " sounds like a statement from experience haha. oh the joys! the worst is how they always seem to randomly end up in enclosures and almost always want to short something important! ha.

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So I was able to get the wood to finish this (it’s a little piece of wood, but what a pain to get during these times…).

While I left a slot on the right to pass the power cable to the tested module, I finally made something else…
I hacked one of @analogoutput’s busboards, which are the size of a Kosmo module !
Three power connectors on the front of the frame, to power the module(s) under test, with a switch to shut them down in case some magic smoke is seen or smelled…

Front:


Back (my phone decided this image looks better in portrait mode…):

And finally installed in my “debugging frame”…

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