Yamaha CS80

Max Fazio wrote:
> Hi all
> This is for Yamaha's CS80 experts: can anyone tell me once for all what in the filter does respond to keyboard velocity?
> What I can hear is a plain velocity-to-cutoff using the panel BUT I'm pretty sure I can hear a velocity-to-attacklevel when using some presets, 
Well, it's a bit hard to trace, but according to the huge overall 
schematic, it only affects cutoff.  The Initial Brilliance comes from 
the TRG-I board, which, according to the overall schematic, only goes to 
the R51 and R52 boards.  These boards are just resistor control voltage 
mixers that drive the filter cutoff voltages to the M (voice) boards.  
Initial level to the M boards appears to come straight from the tone 
selector boards.

I actually don't like the whole initial level/attack level for the 
filter E.G.  The E.G. chips for the filter and VCA both have initial 
level and sustain level inputs, but the filter one has the sustain level 
grounded, while the VCA one has initial level grounded.  Way back when I 
had a CS-60, I modified each M board by grounding the initial level 
inputs to the filter E.G.s and moving the signal to the sustain level 
input.  This made the initial level slider control sustain and made it 
work like a normal E.G.  I really liked this, and it was pretty easy to 
do, but it will mess up some presets.

 David