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Aphex Twin used this on many tracks - it's one secret behind his ambient pads on his early works (and several new tracks). He even released the patch memory dump on SoundCloud. A lot of the sounds were first heard on Selected Ambient Works 85 -92. With lots of outboard reverb of course :)
The DX9 may be the best-sounding 4-operator FM synthesizer ever produced by Yamaha. It has that "original DX7" analog output stage - sounds very different from the DX21, for example, which I have also owned.
My opinion is that 4-operator FM synthesizers tend to produce a different palette of sounds than do 6-operator FM synthesizers. I feel that 4-operator FM is to 6-operator FM what single oscillator analog synthesizer is to triple oscillator analog synthesizer.
If that is the case, then the DX9 would (and does) excel as THE Eighties FM bass machine. And yes, it is sine-wave only pure FM - that's how I like it.
Ridiculously underrated synthesizer.
Specifications
Polyphony: 16 voices
Oscillators: Digital 4 operator FM synthesis
LFO: Standard modulation
Filter: None
VCA: ADSR
Keyboard: 61 keys
Memory: 20 patches
Control: MIDI
Manual
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