Dreamer,
You said
"A real drummer, sampled while playing a groove for -say- eight bars has nothing to do with a midifile playing eight bars with a sampled drum kit, even a multi-layered one. That is because the drummer will hit each time the hi-hat or the snare or the ride cymbal not only with a different velocity, but in a different place (side, center, bell, etc), with a different accent and so adding nuances that would be impossibile to reproduce with a midi sequence and a sampled drum set."
This is accurate, but why was Ketron able to add sample drums ? Because drums do not need to respond to chord changes.. which in part is the brillance of the SD1 technology.
I know you know this, but many people do not understand how it was done !
Integrating guitar loops etc.. is another ballgame..
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