Yeah, this is one part of the CS80 that I would not want to emulate exactly in a VA/Origin. I'd rather have choices, like on the Oberheim 4/8-Voice, which let's you select different key assignment algorithms, each of which suits a particular type of sound and/or playing style. Combine that with Yamaha's brilliant Sustain I/II choices and you can do about any style of mono or poly playing. I don't even want to think of what it would take to interface them, but it could you imagine (visually and sound-wise) a CS80 with an Oberheim 8-SEM cabinet slaved to it! Now there's an inexpensive, simple way to get the LEDs to tell which voice is playing :^) David The Old Crow wrote: > This is what you get when a team of organ engineers use their key > assigner logic for a synthesizer. ;) On the EX-2 each manual can sound > 7 voices each, but together they can only sound 11. They use the same > ring memory table in the GX-1 and key assigner of the CS 50/60/80. > There is a somewhat cryptic explanation in the CS service guide, pages > 11 to 19, describing the encoder for 4 voices. JH references the > service guide on his CS50 page, > > http://home.debitel.net/user/jhaible/jh_cs50.html > > If you look closely you'll see the actual electrical operation of the > key scanner is ternary, not binary, it uses both -6.5v to 0 and 0 to > +8.5v to derive logic states. > > Crow > /**/ > > Colin f wrote: > > The GX has all its voice cards in 80 pin 0.1" card edge sockets, so swapping > > round a bad card is simple. > > > > > >> I'd be interested to find that out too. > >> The GX is odd. I assume it keeps a list of free voices in least recently > >> used order, assigns the voice at the head of the list to a new note and > >> sends that voice to the end of the list when it is released. > >> After an initial clear, for a repeated single note, it starts at voice 2, > >> then cycles thru 3,4,5,6,7,1, back to 2... > >> If you play an overlapping note before the first cycle thru 7 has complete, > >> it plays the second note on the next voice. > >> But once thru the cycle of 7, a second note will always be on voice 8. > >> That suggests to me that the intial state of the LRU list is > >> 2,3,4,5,6,7,8,1. > >> Once you go through the first cycle, it skips voice 8, leaving 8 at the head > >> of the LRU, where it stays until at least two notes are overlapped. > >> One particularly odd thing is that if voice 8 has been brought in during a > >> cycle of single notes, on release it seems to put both voices 8 and 7 at the > >> end of the LRU list, so voice 7 is not used as soon as you'd expect. > >> As you might imagine, mimicking this behaviour precisely in software is > >> going to be a fun job. > >> >
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Re: [yamahacs80] Voice allocation ?
2009-02-18 by David Rogoff
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