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Yamaha SK20

(image courtesy of Yamaha)

Released: 1980

MSRP: Y231,000


Adds presets and more programmability to SK-15 Architecture Class: Conventional (subtractive).

Ebay Description:

The Yamaha SK20 is a 61 key, 7 voice analog ensemble synthesizer, featuring organ, string, and poly-synth sections, dedicated organ and string/synth brilliance, tremolo, vibrato, string and mix volume pedal inputs, and dedicated Polysynth, Organ, and tone cabinet outputs. The synth section also features a slow attack button, release, and a resonant low pass filter with dedicated ADSR envelope. The organ section features 7 stops and an (AR) envelope.


Form Factor Dimensions Weight Audio Input Audio Output Communication Port Control Input Control Output Switch Input Power
61 keys W:1000mm(39.375in) H:158mm(6.25in) D:406mm(16in) 15kg(33lbs) no mix Polysynth Organ tone-cabinet(11pin) no no no sustain AC (30W)


Compatibility Multitimbral Memory Program Memory External Storage External Programming UI Input UI Output
- N/A organ:2 polysynth:3 string:2 (preset) no no dedicated sliders/knobs LED


Multitimbral Polyphony Unison Architecture
3 (Organ and polysynth can be split) 7 split:7+7 no VCO->VCF->VCA+ VCO->VCF->VCA


Effects Pan Modulator Volume Modulator Headphone
"Ensemble" chorus no EG Tremolo pedal yes


Arpeggiator Arpeggiator External Sequencer Sequencer Memory Sequencer External Continuous Program Change
no N/A no N/A N/A 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
Organ analog square? click:2 1' 2' 2.6' 4' 5.3' 8' 16' (mix) no no Vibrato no
Polysynth analog variable saw/square synth:8-16' string(mix):8'16' no no Vibrato no


Name Signal Class IC Resonant Shape Frequency Modulator Resonance Modulator Shape Modulator
Organ-Brilliance analog ? no band pass (+-7dB at 5kHz) no no no
Polysynth-Brilliance analog ? no band pass (+-12dB at 5kHz) no no no
VCF analog ? yes 12dB low pass saw8':6dB band pass VCF-EG no no


Name Level Rate Loop Polarity Trigger Level Modulator Rate Modulator
OrganEG - DR no no key no no
PolysynthEG - switch:A R no no key no no
VCF-EG sustain attack decay release no no key no no


Name Waveform Delay Polarity Sync Delay Modulator Level Modulator Rate Modulator
Vibrato triangle? yes no no no no no
Tremolo triangle? no no no no no 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