XAOC Devices - Karl-Marx-Stadt


Karl Marx Stadt is a front-end for Doepfer's DIY synth and it's a super-easy solution to turn it into an Eurorack synthesizer voice. No soldering and screwing required, just plug and play! It takes 5 seconds!



The expander module makes everyone unwilling to DIY very happy as it will save you the purchase, wiring and soldering of potentiometers, sockets and the pesky drilling and lettering of a face plate or a housing and finally the power supply issue!

All controls, and sockets are integrated in the KMS, all you need is to connect the DIY synth's pin headers to the corresponding sockets of the KMS and to install the cable for the temperature compensation. Finally connect the ribbon cable to the Eurorack powre supply and THAT'S IT! Takes five seconds only!

The Karl Marx Stadt uses all patch points of the DIY synth and even expands it a little: The filter's feedback loop has been broken up and can be patched freely now. Number two: the inverter circuit providing the inverted envelope signal can be used autarkly as well. There's a normalization from the ADSR out to the, now available, inverter input socket. And the slew limiter can be used separately, too

As the module is normalized internally you can use the DIY synth instantly, all you need to connect is a pitch CV and a gate signal!

The Doepfer DIY synth is not included and has to be purchased separately, preferably here ;)

XAOC name their products after places and cities of the former Eastern Bloc. Karl-Marx-Stadt is the communist name of Chemnitz in Germany..


VCO inputs: 1V/oct, Sync, FM exp, FM lin, Slew, PW mod.
VCO outputs: pulse, saw, slew

LFO outputs: pulse and triangle

VCF inputs: audio 1 & 2, CV 1 & 2, resonance feedback
VCF outputs: lowpass, bandpass, highpass, low-notch-high

ADSR: gate in, ADSR out, inverter in, inverter out

VCA: audio inputs 1-3, CV inputs 1 & 2, audio output


3U Eurorack expansion module, 42HP wide, 40mm deep
power consumption: 170mA

0.438 kg
Article Number
former retail price: €242.86

This item is discontinued or sold out and no longer available, please feel free to look for comparable new stuff in the following categories.


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