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"Made in the 1970s, System 3000 modular synthesizers were popular with those experimenting with electronic music. They were reputedly sold to Karlheinz Stockhausen and were distributed in the United States by Bob Moog's Big Briar Inc.
The kit on offer belonged to my late brother, who worked for many years in the sound industry.
The keyboard and modules on offer have not been used in over 20 years, but appear to still be in reasonable condition. There is no apparent damage to the circuitry or the module fascias. The small number of screws on the keyboard appear superficially rusty, though they still turn easily. There are a few scratches to the metal casing of the keyboard."
"Included in this set are the following genuine Synton items:
(the descriptions are taken from websites and mean little to me – so I regret that I am unable to answer specific questions about their function)
KBM 35 Keyboard
44-key monophonic keyboard with scale control.
3005 EGR
Discrete ADSR with manual trigger button and LED.
3006 MPL - Multiple
3015 MXA
3-1 mixer with unity-gain input.
3017 VCF
State-variable 12 dB filter. One output is Band pass, the other has a control for low-notch-high pass.
3021 VCO (x2)
Uses a Curtis chip. Triangle, saw and variable pulse outputs, hard sync and PWM inputs.
3209 VCA
Dual VCA with positive gain-offset controls. This can be used for feeding a sound to the output without an envelope while testing or tuning.
3211 PRM/NRG
Ring modulator, white/pink noise with level control, VLF noise with level control.
3218 INV / SLR
Dual inverter with offset controls (also used as variable voltage source) and slew limiter with rise and fall controls. This can be used as simple AR envelope.
3223 2LFO
Dual LFO with VC speed. Square and triangle outputs.
3235 ENV / CPR
Envelope follower and comparator with reference level control."
