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OB-6 Keyboard - Image 1

OB-6 Keyboard

KeyboardAnalogPolyphonic

Born from a collaboration between Sequential and Tom Oberheim, this synth revives the iconic SEM filter in a modern 6-voice analog powerhouse, delivering that classic Oberheim warmth with a twist of contemporary control.

At its core, two discrete VCOs per voice offer continuously variable waveforms from sawtooth to pulse and triangle, complete with hard sync, sub-octave generators, and detune for everything from subtle chorusing to wild instability. The standout SEM-inspired filter provides low-pass, high-pass, band-pass, and notch modes with resonance that sings, paired with cross-modulation and dual envelopes for dynamic shaping. A 49-key semi-weighted keyboard with velocity and channel aftertouch feels responsive under your fingers, while backlit pitch and mod wheels, plus a spring-loaded pitch bend, make performance intuitive. Multimode arpeggiator, 64-step polyphonic sequencer, unison with chord memory, stereo analog distortion, and dual digital effects like lush reverbs, synced delays, and Oberheim's signature phaser round out the signal path—all with true bypass to keep the analog pure. MIDI, USB, and pedal inputs ensure seamless integration.

Players love its fat, organic tones that cut through mixes, praising the hands-on panel and vast preset library of 500 factory plus 500 user sounds. Some note the digital effects can feel secondary to the raw analog core, but that's part of its charm for purists.

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)
Envelopes
-
LFO
1
Effects
Reverb, Delay, Chorus, Flanger, Phaser, Ring Mod
Expression
Aftertouch
Monophonic
Velocity
Yes
MPE
-
Additional
-
Software
-
I/O
Audio In
-
Audio Out
2x 1/4" TRS
Headphone
1x 1/4" TRS
MIDI
In, Out, Thru
MIDI Type
DIN (5-pin), USB
Ports
Other Pedal, Footswitch
Wi-Fi
-
Workflow
Arpeggiator
Yes
Sequencer
Yes
Mod Matrix
-
Memory
-
Measurements
Dimensions
807 x 323 x 117 mm
Weight
9.5 kg
Last updated Mar 21, 2026