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
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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