Sequential Dave Smith Instruments OB-6 Keyboard 6-Voice Analog Synthesizer Keyboard

Dave Smith & Tom Oberheim Collaboration

The OB-6 is the result of two of the greatest minds in synthesizer design coming together. Dave Smith and Tom Oberheim are revered for their innovative and influential poly synth designs, with each bringing their own unique qualities to the OB-6's design. The OB-6 combines the bold, signature sound of Oberheim with Dave Smith's modern innovations, resulting in a poly synth that provides the best of vintage synthesizers and modern technology. The synth itself features a 49-keybed with 2 oscillators and a 64-step polyphonic step sequencer.

Vintage SEM Tone

The sound engine in the OB-6 was developed and inspired by Tom Oberheim's original SEM, which served as the keystone of his 4-note and 8-note synths. The sound engine features two discrete voltage-controlled oscillators (and sub-oscillator) per voice, plus continuously variable waveshapes. The 2-pole, state-variable resonant filter provides a range of parameters including low-pass, high-pass, notch and band-pass functionality.

Easy To Program And Play

The OB-6 is also designed for straight-forward simplicity, resulting in a seamless user experience that is easy to program and play. The front panel features a knob for pretty much every function available, including both the 500 factory programs and 500 rewritable user programs. The manual button enables live panel mode, where the sound of the OB-6 switches to its current front panel settings, giving you a visual representation of what you hear. The semi-weighted, four-octave keyboard featuring velocity and channel aftertouch for added expression and dynamic changes.

Dual Effects

There is also a range of varied effects built-in to the synth, allowing you to tweak and edit your sounds as you play. Providing studio quality effects such as: Delay, Reverb, Chorus, Flangers, Phase Shifter and Ring Modulation. These digital effects run at 24-bit/48kHz resolution with a true bypass that ensures the full analog signal path.

Poly Step Sequencing and X-Mod

The X-Mod function (Crossmodulation) allows you to modulate the frequency of two oscillators, expanding your tonal palette and creating the means to build unconventional and unique sounds. The modulation sources are the filter envelope and oscillator 2, with both featuring bio-polar controls. You can then choose from a range of destination including Oscillator 1 freq, Oscillator 1 pulse width, filter cutoff, shape and more. In addition to the crossmodulation, the OB-6 features a polyphonic step sequencer which supports up to 64 steps and up to 6 notes per step. This versatile sequencer allows you to arrange and create sequences and synth to an external MIDI clock. The unison mode in the sequencer features a configurable voice count, key modes and chord memory.

Technical Specifications

• Two discrete VCOs per voice
• Continuously variable wave shape - sawtooth and variable-width pulse, plus triangle on oscillator 2)
• Pulse width per oscillator
• Hard sync capability; oscillator 1 syncs to oscillator 2
• Squave wave sub-octave generator (oscillator 1) per voice
• Low frequency mode (oscillator 2)
• Keyboard tracking on/off (oscillator 2)
• Oscillator detune amount for increased tuning instability, ranging from subtle to extreme

• Oscillator 1 amount
• Oscillator 1 sub-octave amount
• Oscillator 2 amount
• White noise amount
• State-Variable Filter
• Two-pole, resonant, filter per voice with low-pass, high-pass, band-pass, and notch functionality inspired by the original Oberheim SEM filter
• Bi-polar filter envelope amount
• Velocity modulation of envelope amount
• Keyboard tracking: off, half, full

• Four-stage (ADSR) envelope generator
• Velocity modulation of envelope amount
• Amplifier Envelope
• Four-stage (ADSR) envelope generator
• Velocity modulation of envelope amount

• Five wave shapes: sine, sawtooth, reverse sawtooth, square, and random (sample and hold)
• Clock sync (internal or external MIDI clock)
• Initial amount
• Mod destinations: oscillator 1 frequency, oscillator 2 frequency, oscillator 1 and 2 pulse width, filter cutoff, filter mode, amp

• Sources: filter envelope (bi-polar) and oscillator 2 (bi-polar)
• Destinations: oscillator 1 frequency, oscillator 1 shape, oscillator 1 pulse width, filter cutoff, filter mode, normal to bandpass filter

• Selectable note value: 16th note, 8th note triplet, 8th note, dotted 8th note, quarter note
• One, two, or three octave range
• Up, down, up/down, random, and assign modes

• Polyphonic step sequencer with up to 64 steps and rests

• Stereo analog distortion
• Dual, 24-bit, 48 kHz digital effects, including: reverb (room, hall, plate, spring), delay (full bandwidth digital delay and emulated bucket brigade), chorus, flanger, phase shifters, and ring modulator
• Delay sync
• True bypass maintains fully analog signal path when digital effects are off

• Full-sized, semi-weighted, 4-octave keyboard with velocity and aftertouch
• Backlit pitch and mod wheels
• Spring-loaded pitch wheel with selectable range per program (1 to 12 semitones up and down)
• Transpose controls for an 8-octave range
• Hold switch latches held notes on

• Unison (monophonic) mode with configurable voice count, from one to all six voices, chord memory, and key modes
• Manual switch: when on, the front panel is live; what you see is what you hear

• 500 user and 500 factory programs in 10 banks of 100 programs each
• Direct program access, including single-button access to the current set of 10 programs

• Left/mono and right audio outputs (2 x 1/4'' phone jack)
• Headphone output (stereo, 1/4'' phone jack)
• MIDI in, out, and thru ports
• USB for bidirectional MIDI communication
• Filter cutoff expression pedal input
• Volume expression pedal input
• Sustain footswitch input
• Sequencer start/stop footswitch input

• IEC AC power inlet for internal power supply
• Operates worldwide on voltages between 100 and 240 volts at 50 to 60 Hz; 30 watts maximum power consumption