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Subject: Re: [oldsynths] Modifying a CS60

From: Scott Rider <oldcrow@...>
Date: 2007-09-15

CS80 aftertouch uses force-sensing resistors--actually, they are a
stepped ladder of resistances with the resistances 1/x adding (parallel)
the firmer the key is held down. One is under each key and not part of
the key up/down scanning circuit. The TKC board is a channel selector
circuit that maps a given AT signal to the modulation VCAs of the voice
currently assigned to sound the note.

The CS-50/60 are not like this as they use an optical shutter operated
by global key pressure and not individual key pressures. You would have
to mount FSRs under each key, after tweaking each key to have a 'strike
piston' that pushes on the FSR, then use a similar channel selector
circuit and bank of T/H amps to map the AT signals to the correct voice
modulation VCAs. At least the M boards have the same modulation setup,
the 'unison' modulation from the optical AT would have to be split away
from each M board, and 8 new signals brought down to the new PCB that is
handling AT channel selection. Not a weekend task. ;)

Crow
/∗∗/

ascii_me wrote:
> Anyone on this board have any interesting mods for the CS-60?
> I have aftertouch on it, but can it be modded to be poly aftertouch
> like the CS-80?
>
> Regards
> Rory McDonald
> Oldsynths Moderator
>
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