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SIEL Expander

Expander (image courtesy of SoundDoctorin)

Released: 1984



Desktop DK 600 expander module (no direct editing) Architecture Class: Conventional (subtractive).

Ebay Description:

The SIEL Expander is a desktop, 6 voice (velocity sensitive) analog synthesizer, featuring programmable dual oscillators, resonant low pass filter (24dB SSM), envelope, and 3 LFOs, along with 95 program memories, tape interface, and MIDI.


Form Factor Dimensions Weight Audio Input Audio Output Communication Port Control Input Control Output Switch Input Power
desktop ? ? no mono MIDI: IN OUT THRU tape volume (5 pin DIN) filter (5 pin DIN) no no AC


Compatibility Multitimbral Memory Program Memory External Storage External Programming UI Input UI Output
Opera 6 DK 600 Kiwi Expander N/A 95 tape no menu LED


Multitimbral Polyphony Unison Architecture
no 6 no DCO1+DCO2->VCF->VCA


Effects Pan Modulator Volume Modulator Headphone
none no EG Velocity no


Arpeggiator Arpeggiator External Sequencer Sequencer Memory Sequencer External Continuous Program Change
no no N/A MIDI no


Key Pressure Chord Memory External Control External Sustain Key Scaling Velocity Curves
no yes 4


Name Signal Class Waveform Octave Range Amplitude Modulator Harmonics Modulator Pitch Modulator Wave Assign Modulator
DCO1 digital saw pulse 4' 8' 16' no PWM:LFO3 LFO1
DCO2 digital saw pulse 4' 8' 16' no PWM:LFO3 LFO1
Noise digital noise:pink 4' 8' 16' no no no


Name Signal Class IC Resonant Shape Frequency Modulator Resonance Modulator Shape Modulator
VCF analog SSM2044 yes 24dB low pass EG key LFO3 pedal no


Name Level Rate Loop Polarity Trigger Level Modulator Rate Modulator
EG sustain attack decay release no no no no Velocity


Name Waveform Delay Polarity Sync Delay Modulator Level Modulator Rate Modulator
LFO1 triangle? no no no no no
LFO2 triangle? no no no no no
LFO3 square triangle no no no no no
Conventional Models
Orchestra Mono Cruise Orchestra2 OR 400 Opera 6 DK 600 Kiwi
Expander DK 700 DK 70 EX 80 DK 80