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OB-6 Polyphonic Analog Keyboard Synthesizer - Image 1

OB-6 Polyphonic Analog Keyboard Synthesizer

KeyboardAnalogPolyphonic

Born from the dream team-up of Tom Oberheim and Dave Smith, this synth revives the raw, aggressive SEM tone that defined '70s polyphonics, but packs it into a modern 6-voice hybrid powerhouse ready for today's studios.

At its heart, two discrete analog VCOs per voice deliver continuously variable waveshapes—from sawtooths to pulses, with triangle on osc 2, plus a square sub-octave on osc 1 and hard sync for thick, unstable detuning. The classic 2-pole state-variable filter nails Oberheim's low-pass, high-pass, band-pass, and notch modes with resonant bite, driven by dedicated ADSR envelopes for filter and amp, both velocity-sensitive. X-Mod lets osc 2 or the filter envelope twist osc 1 freq, shape, pulse width, or filter params for wild timbres, while a versatile LFO with five shapes (including random) hits osc freqs, pulse widths, cutoff, and more. Hands-on knob-per-function panel includes pitch/mod wheels, a 49-key semi-weighted keyboard with velocity and aftertouch, poly step sequencer up to 64 steps, arpeggiator, and 1000 programs. Dual 24-bit/48kHz digital FX—reverb, delays (BBD/tape), chorus, flanger, phaser, ring mod, plus analog distortion—layer in via true bypass to keep the signal pure analog. It's compact at 32 x 12.7 x 4.6 inches and 20 lbs, with dual mono outs and headphone jack.

Players love its immediate, knob-tweaky workflow and that unmistakable Oberheim aggression—fat leads, lush pads, punchy basses—that outshines vintage units in flexibility, though some note the 6-voice limit feels tight next to beefier modern polys.

Released

2016

Status

In Production

Synthesizer
Format
Keyboard
Type
Subtractive
Internal Battery
No
Voice
A/D
Analog
Polyphony
Polyphonic
Oscillators
2
Oscillator Type
VCO (Voltage Controlled)
Voices
6
Filter
Lowpass, Highpass, Bandpass, Notch, 12dB/oct (2-pole), State Variable
Envelopes
2
LFO
1
Effects
reverb, delay, chorus, flanger, phase shifter, ring modulator, distortion
Expression
Aftertouch
Monophonic
Velocity
Yes
MPE
No
Additional
pitch wheel, mod wheel, 49-key semi-weighted keyboard, X-mod, unison mode
Software
-
I/O
Audio In
-
Audio Out
2x 1/4" TS
Headphone
1x 1/4" TRS
MIDI
In, Out, Thru
MIDI Type
DIN (5-pin), USB
Ports
Other Pedal, Footswitch
Wi-Fi
No
Workflow
Arpeggiator
Yes
Sequencer
Yes
Mod Matrix
Yes
Memory
1000 programs (500 user, 500 factory)
Measurements
Dimensions
32" x 12.7" x 4.6"
Weight
20 lbs (9.5 kg)
Last updated Mar 17, 2026