Ensoniq ESQ-1 -1986    Weight = ? Lbs. Number mfg.= 50,000 MRP=$1395

User Manual: Buchty's Ensoniq page
Reset Proceedures: Hidden functions!
Operating System code: Buchty's
MIDI or other control protocol:See Manual above
Software related Links:
Patches or knob settings:factory patches
Circuit Overview: below
Scematics/Service Manual: Buchty's
Common Service Issues/Tips: below
Parts Sources: Keys knobs semiconductors misc
Uncommon chips/modules used:SSM2300 S+H mux, CEM3360 dual vca, CEM3379 filter/voice processor, 5503DOC/ICS1261 Sound Engine, 6500/11 (label 1380 65003/R1121-11) display processor and
Modifications:rev. to an SQ80!
General Info Links: Vintage Synth Explorer

Circuit Overview:
     ESQ1 is an early 'hybrid' synth using ROM based sound information and analog filters. Here is a clip from SDIY:

---On Mon, 1 Oct 2007, John Mahoney wrote:

>> I can hardly believe they were generating software envelopes at 50-60Hz.

Within the Ensoniq ESQ1/SQ80 (1985/87, 68B09 running at 2MHz for 
anything than sound chip access) it's something along 83Hz update rate.

Not timer-controlled, btw., but through some more or less carefully 
timed cooperative multitasking (which makes adding MIDI-clock sync 
pretty much impossible w/o rewriting the entire task/subtask handler 


Service Tips:
     I've only done peripheral things; battery change and cleaning issues on these machines. I recall seeing some power supply issues in the past also possibly but generally they have performed fairly reliably I believe. If anyone is aware of common service issues let me know.

Syntaur has many parts for Ensoniq specifically. Let me know if you need a specific part from my listings in the parts section that you don't find elsewhere or whatever.
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