The trilogy combines a 2 divide down oscillator system(fairly simple string/organ sound with 4 organ drawbars and some phaser effect for strings, attack/decay, 8'/16'pan knob), with a synth section, featuring sync or free with a phase led like the polymoog. But the 'paraphonic' nature of this instrument is unique! It uses 6 envelopes and filters, one assiged to the C's and F#'s, one assigned to C#, G, and so on! An interesting compromised approach to this kind of design. In this way it plays more like a full polyphonic polysynth since you often don't hit those note combinations. However octaves will retrigger the envelope of course on all notes of that octave that are being held.
Another nice feature is there are 8 patch select switches. However 1 is hard assigned to whatever the knobs are set to do. The others may be set with TRIM POTS inside! So you can customize your presets! How often do you see that!? The CEM3320's are set up to sound sweet. Great resonance range. Smooth envelopes of course with CEM3310's and the analog vca's. But this synth is very limited in 'punch' for whatever reason. Good for a some sounds though and nice modulation joystick. Also the "TM Interface" can be used with the Steiner "Master's Touch" for an array of breath control tricks!
Always verify voltages of course on old instruments first. Mine had a bad CEM3330 I recall which can be tough to find. Missing note on one osc. is usually a bad TOS. Missing/noisy notes below certain point bad divider. Missing groups of notes something bad in synth cards. (Eg. bad C and F# all the way is bad card #1 since notes are grouped in half steps up from those notes to each successive card. Eg. C# and G to card 2 etc.). The rare SSM2020 tends to fail taking out the synth section also unfortunately. And bad EG's aren't uncommon.
Ask if you need a specific part. I have a scrap unit. Knobs $5 each.
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