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Yamaha CS-20M

(image courtesy of Yamaha)

Released: 1979

MSRP: Y220,500 ($1595US)


Expands CS10 functionality with dual oscillators and a RAM based memory Architecture Class: Conventional (subtractive).

Ebay Description:

The Yamaha CS-20M is a 37 key, monophonic analog synthesizer, featuring dual oscillators (pulse, sine, saw and triangle waveforms), noise, resonant low|high|band pass filter, dedicated (ADSR) filter and amp envelopes, LFO (saw:down|up, sine, square, S/H waveforms), CV/gate IO, tape interface, and 8 editable presets.


Form Factor Dimensions Weight Audio Input Audio Output Communication Port Control Input Control Output Switch Input Power
37 keys W:849mm(33.375in) H:177mm(7in) D:455.5mm(17.875in) 16kg(35.3lbs) no mono:low/high/balanced no CV gate CV gate sustain portamento AC (28W)


Compatibility Multitimbral Memory Program Memory External Storage External Programming UI Input UI Output
- N/A user:8 (battery backup via 2x AA) tape no dedicated sliders/knobs LED


Multitimbral Polyphony Unison Architecture
no 1 no VCO1+VCO2+noise->VCF+sine->VCA


Effects Pan Modulator Volume Modulator Headphone
no no LFO VCA-EG pedal yes


Arpeggiator Arpeggiator External Sequencer Sequencer Memory Sequencer External Continuous Program Change
no N/A no N/A N/A pitch-wheel mod-wheel portamento-slider brilliance-knob release-slider volume-pedal no


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


Name Signal Class Waveform Octave Range Amplitude Modulator Harmonics Modulator Pitch Modulator Wave Assign Modulator
VCO1 analog pulse saw sine triangle 2-64' no PWM auto-bend CV LFO portamento pitch-wheel no
VCO2 analog pulse saw triangle 2-64' no PWM auto-bend CV LFO portamento pitch-wheel no
Noise analog noise no no no no no


Name Signal Class IC Resonant Shape Frequency Modulator Resonance Modulator Shape Modulator
VCF analog IG00156 yes low|high|band pass key LFO VCF-EG no no


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


Name Waveform Delay Polarity Sync Delay Modulator Level Modulator Rate Modulator
LFO saw:down|up sine square S/H no no no no mod-wheel no
Conventional Models
SY-1 SY-2 CS-10 CS-30 CS-30L CS-50 CS-60 CS-80
CS-5 CS-15 CS-15D CS-20M CS-40M CS-70M CS-01 SK10
SK15 SK20 SK30 SK50D SY-20 AN1x