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OCS-2

Semi-ModularHybridMonophonic

Ever since its debut around 2017, this synth has been a secret weapon for Eurorack builders craving hands-on analog vibes from a digital heart, packing pro-level sound into just 50HP.

At its core, dual digital VCOs dish out 15 waveforms each—including some custom fat ones—with independent or linked tuning up to an octave apart, feeding a CV-controlled mixer, ring modulator, and multi-mode VCF modeled after the classic Moog ladder (24dB/oct low-pass with resonance, plus 12dB low/band/high-pass options). Three LFOs bring shape-morphing flexibility (two configurable, one gate-synced with rhythmic waves and CV speed control), joined by a versatile CV generator offering attack/release, dual LFO, random, or step algorithms. A single ADSR drives the VCA, while four effects—distortion, delay, bitcrush, waveshaper—add grit; everything ties together via a powerful digital mod matrix using the 2-octave micro-switch keyboard panel for patching without cables. Stereo line in with envelope follower, MIDI, three CV/gate ins, and a light sensor for gesture control round it out, all running at 48kHz audio with 24-bit I/O and 32-bit processing in a knob-per-function paradise of 30 precise 12-bit pots.

Knob perverts and players alike dig its immediate tweakability and thick, pleasing tones—audio demos still turn heads for that analogue-style punch without the drift—though some note the open-source Arduino Due roots mean it's a tinkerer's dream, not always plug-and-play polished.

Released

2017

Status

In Production

Synthesizer
Format
Semi-Modular, Eurorack
Type
Subtractive, Digital
Internal Battery
No
Voice
A/D
Hybrid
Polyphony
Monophonic
Oscillators
2
Oscillator Type
Digital
Voices
1
Filter
Lowpass, 24dB/oct (4-pole), Multimode
Envelopes
1
LFO
3
Effects
distortion, delay, bitcrush, waveshaper
Expression
Aftertouch
No
Velocity
Yes
MPE
No
Additional
2 octave keyboard, light sensor, ring modulator, CV generator
Software
-
I/O
Audio In
1 stereo
Audio Out
1 stereo
Headphone
0
MIDI
In
MIDI Type
-
Ports
CV/Gate
Wi-Fi
No
Workflow
Arpeggiator
No
Sequencer
No
Mod Matrix
Yes
Memory
No
Measurements
Dimensions
50 HP
Weight
-
Last updated Mar 17, 2026