Open Box Oberheim OB-6 6 Voice Analog Synthesizer Level 1

Some instruments are born from innovation. Others are born from collaboration. The OB-6 analog synthesizer exists because two of the most influential figures in analog synthesis history—Dave Smith and Tom Oberheim—decided to build something together that had never quite existed before. Drawing directly from the bold, unmistakable voice of Oberheim’s original SEM designs and pairing it with modern performance tools, the OB-6 delivers six discrete analog voices powered by true voltage-controlled oscillators, a state-variable filter and an entirely analog signal path. The result is a 49-key poly synth that feels rooted in history while remaining unmistakably current in sound, control and playability.

Vintage SEM Architecture With Modern Stability

At the core of the OB-6 is a sound engine inspired by Tom Oberheim’s original SEM, known for its wide, harmonically rich character. Each voice features two discrete VCOs plus a sub-oscillator, offering continuously variable waveshapes that move smoothly from sawtooth to pulse alongside a dedicated triangle wave. The classic two-pole, state-variable filter provides low-pass, high-pass, band-pass and notch modes, giving players a broad tonal range that shifts effortlessly from silky pads to aggressive leads while preserving the immediacy and warmth of an all-analog path.

Expanded Modulation and Expressive Control

Beyond its vintage foundation, the OB-6 adds deeper modulation tools that invite exploration. X-Mod expands the classic architecture by routing the filter envelope or oscillator 2 to multiple destinations for dramatic tonal movement and evolving textures. Velocity and channel aftertouch further enhance expressiveness, allowing subtle performance dynamics or bold modulation changes to be shaped directly from the keyboard without breaking creative flow.

Polyphonic Sequencing and Arpeggiation

The OB-6 is designed to inspire composition as much as sound design. Its polyphonic step sequencer supports up to 64 steps and multiple notes per step, making it possible to build harmonically rich sequences that move and change over time. An onboard arpeggiator with multiple modes and clock sync adds rhythmic flexibility, whether locked tightly to external MIDI gear or driving a performance on its own.

Studio-Quality Effects With True Analog Bypass

A dual effects section adds depth and character without compromising the instrument’s analog integrity. The OB-6 includes high-resolution digital effects such as reverbs, delays, chorus and flanging alongside faithful recreations of Oberheim’s classic phase shifter and ring modulator. When effects are disengaged, a true bypass preserves the fully analog signal path, keeping the core tone intact for purists and studio applications alike.

Hands-On Design Built for Stage and Studio

Everything about the OB-6 encourages direct interaction. A knob-per-function front panel places nearly every sound-shaping control within immediate reach, while live panel mode ensures what you see is exactly what you hear. Housed in a four-octave, semi-weighted keyboard with walnut end panels and comprehensive connectivity, the OB-6 stands as a modern analog instrument shaped by history, designed for players who value character, immediacy and musical depth.