O.B.S.Zenith (prototype)

One Board Synth

All analog module based on the Electro Smith submodules 3340 VCO V1 and 2144 LPF V1.


  • 2 VCO with independent triangle, saw and pulse outputs
  • Low pass filter
  • Envelope generator (AR)
  • VCA
  • Ring modulator

Both VCOs can be used as a LFO (indeed a VCLFO).

Low pass filter in self oscillation can be used as a sine VCO with 4 octaves tracking.

Envelope generator could be used as a manual LP filter or slew limiter.

This module is capable of a wide variety of results, from 'classic analog' to super weird.

Every part of the module can be used independently.

Expected input voltages:
-Pulse With Modulation: 0 to 5V
-VCO v.oct input: -8 to +12V
-Filter frequency v.oct input: -6V to +6V