What it is and what it was built for
A polyphonic analog subtractive synthesizer released in December 1980. Built to replace the OB-X with streamlined manufacturing, improved playability, and expanded real-time control over voice allocation and timbre.
How it works, in terms a player would use
It uses Curtis integrated circuits for oscillators and filters. It offers selectable 2-pole or 4-pole filtering. It replaces OB-X cross modulation with Filter Envelope modulation for oscillator 2. It supports keyboard splitting and layering. It connects to other Oberheim gear via the Serial Buss — a pre-MIDI parallel bus.
What it does better than anything else
It layers and splits voices more intuitively than the OB-X. Its filter envelope modulation of oscillator 2 gives immediate pitch-sweep articulation without patching. The Curtis ICs deliver consistent tuning and simplified servicing.
What it does badly
It cannot cross modulate oscillators. It lacks discrete-circuit character in its oscillators and filters. It has no MIDI — only the proprietary Serial Buss, limiting integration outside Oberheim’s 1980–81 ecosystem.
What people made with it
Layered brass stabs, split bass-and-pad textures, and evolving lead lines — particularly in early 1980s pop, R&B, and film scores where thick, stable analog polyphony was required.
Who should use it, and who should not
Players who value hands-on layering and splitting, need reliable tuning across 4–8 voices, and work within a vintage Oberheim ecosystem. Not for those needing FM, digital control, or discrete-circuit unpredictability.
Is it worth your time
Yes, if you need thick layered pads or split bass-and-lead textures from a single analog voice architecture. No, if you require cross modulation, discrete-circuit warmth, or MIDI timing precision.
