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K150 - Image 1

K150

RackmountDigitalPolyphonic

Back in 1986, this rackmount pioneer brought real-time additive synthesis to the masses with a massive bank of 240 digital oscillators—letting you sculpt harmonics from the ground up like few others could.

It's a 4-space rack unit with 16-voice polyphony, a single LFO for pitch vibrato, digital filters, and 256-stage envelopes for precise amplitude control. Controls live on a 24-button front panel under a 16-character LED display, handling everything from master tuning and transposition to layering up to three keyboard regions with seven layers each for splits, stacks, and velocity switches. MIDI In/Out/Thru via 5-pin DIN, polyphonic aftertouch, sustain pedal input, and stereo audio out round it out, with 186 onboard patches expandable to 255. The included Fourier Synthesis upgrade lets you edit velocity curves, envelopes, and tuning for custom instrument models, all modifiable via pitch bend, EQ, chorusing (by voice stacking), and full MIDI control.

Though it flew under the radar commercially, enthusiasts and researchers cherished its depth for thick, evolving timbres—perfect for those chasing unique, programmable sounds in a pre-sampler world.

Released

1986

Status

Discontinued

Synthesizer
Format
Rackmount
Type
Additive
Internal Battery
No
Voice
A/D
Digital
Polyphony
Polyphonic
Oscillators
240
Oscillator Type
Digital
Voices
16
Filter
Yes
Envelopes
-
LFO
1
Effects
No
Expression
Aftertouch
Polyphonic
Velocity
-
MPE
No
Additional
-
Software
-
I/O
Audio In
-
Audio Out
1 stereo
Headphone
-
MIDI
In, Out, Thru
MIDI Type
DIN (5-pin)
Ports
Sustain Pedal
Wi-Fi
No
Workflow
Arpeggiator
-
Sequencer
-
Mod Matrix
-
Memory
186 patches (up to 255)
Measurements
Dimensions
-
Weight
-
Last updated Feb 26, 2026