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"Custom modular style SK-1 by Diabolical Devices features:
24 point circuit bending patch bay with 4 patchable toggle switches and 2 patchable momentary buttons. Patch bay uses 1/8" connectors and cables are included.
Three stage square wave generator with LFO. This can be used as a stand alone synth, be patched into bending points, or played into sample input of SK-1 and transposed to keys, circuit-bent, and resampled..... Has 1/4" and 1/8" audio outputs for square waves

Master pitch control (SK) this affects the pitch of all keyboard sounds, samples and drums. This can be completely bypassed via toggle switch.
MIDI input with midi channel selector
panel mounted 1/4 audio output for SK-1 (white jack) and 1/4" sampling input for SK-1. Also DC power input with master power switch
If you like the modular case we made a few extra and will be listing some cases with blank panels for your own project. Please note this particular case was built for this SK -1 which is slightly shorter than normal because of an experiment. The rest of the cases fit a standard SK-1 (see pics)"