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Sequential_Circuits Pro-One

Pro One
Pro One

Released: 1981

MSRP: $995US


Monophonic Prophet5. Architecture Class: Conventional (subtractive).

Ebay Description:

The Sequential Circuits ProOne is a 37 key, monophonic analog synthesizer, featuring programmable dual oscillators, resonant low pass filter (24dB CEM), dual envelopes, glide, and LFO, along with an arpeggiator and sequencer.


Form Factor Dimensions Weight Audio Input Audio Output Communication Port Control Input Control Output Switch Input Power
37 keys ? ? Filter stereo no Filter:1V/oct (0-10V) CV:1V/oct (0-10V) Gate/Clk:+5V CV:1V/oct Gate:+5V no wired


Compatibility Multitimbral Memory Program Memory External Storage External Programming UI Input UI Output
N/A N/A - no no button/knobs LED


Multitimbral Polyphony Unison Architecture
no 1 N/A VCO1+VCO2+Noise->VCF->VCA


Effects Pan Modulator Volume Modulator Headphone
no no VCA-EG shared


Arpeggiator Arpeggiator External Sequencer Sequencer Memory Sequencer External Continuous Program Change
yes no yes 40 notes no Pitch-Wheel Mod-Wheel no


Key Pressure Chord Memory External Control External Sustain Key Scaling Velocity Curves
no no no no yes no


Name Signal Class Waveform Octave Range Amplitude Modulator Harmonics Modulator Pitch Modulator Wave Assign Modulator
VCOA analog pulse saw 4 no FM:VCOB PWM: LFO Noise VCF-EG VCOB glide LFO Noise Pitch-Wheel VCOB VCF-EG
VCOB analog pulse saw triangle 4 LFO no PWM: LFO Noise glide LFO Pitch-Wheel Noise
Noise analog noise - no no no


Name Signal Class IC Resonant Shape Frequency Modulator Resonance Modulator Shape Modulator
VCF analog CEM3320 yes 24dB low pass key LFO Noise VCF-EG VCOB no


Name Level Rate Loop Polarity Trigger Level Modulator Rate Modulator
VCA-EG sustain attack decay release no no no no no
VCF-EG sustain attack decay release no no no no no


Name Waveform Delay Polarity Sync Delay Modulator Level Modulator Rate Modulator
LFO saw:up square triangle no no no Mod-Wheel no
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