Yamaha CS80

Hi Scott and Group,

another thought about the double trigger issue.

If you prolong the trigger with a one-shot (what you described), this 
should be a cure for _wrong_ notes to cause dissonance: you ascertain 
that the trigger is long enough for the CV to reach its final (right) 
value. But you'd still have two voices sounding instead of one 
(especially with a long release time or held damper pedal).

An alternative could be to mask the first part of the trigger, i.e 
only to allow it to reach the keyboard scanner electronics if it's at 
least of some minimal length. (As long as it takes for the CV to be 
completely sampled.)
But this also means that *every* trigger would be delayed by that 
amount of time, which, depending on how much time we actually need, 
may affect the resposiveness of your playing. (Delays are always bad 
for a good timing.)

So here is another idea:

For a trigger that's shorter than a certain time (let's say 50ms), 
the release time of the respective voice is decreased and/or the 
sustain pedal function is disabled for this voice. As everything is 
under voltage control inside a CS-80, this should be easy from an 
electronic point of view. (Don't know about the mechanical aspect, 
number of extra wires etc.)

Example: 

You have a voice with a release time of 2 seconds.

Now a bouncing key passes a trigger of 5ms to voice #1,
and a trigger of 200ms (as long as you hold the key) to voice #2.

Asuming voice #1 cannot build up its correct pitch CV in 5ms, you'd 
have a wrong note sustaining for 2 seconds without a correction.

Applying my idea (if it works, that is), both voice #1 and voice #2 
would have their Release time temorarily reduced to "zero" (a couple 
of milliseconds) - but only for a tim espan of, say, 50ms after the 
trigger.
To voice #2 this would make no difference: as long as the key is 
held, the zeroed release parameter doesn't matter (we're not in th 
erelease phase yet!).
To voice #1 (the wrong one), it makes _all_ the difference: as soon 
as the glitch (double trigger event) is over, the voice goes off 
with "zero" release time (just a ghost note, where pitch perception 
isn't really possible anyway).

What do you think?
Could this work?

Best Regards,

JH.




>   I tinkered with a corrective circuit, but am unsure if the 
correction 
> is 'better' (essentially a one-shot with a time of 50ms or so for 
each 
> trigger switch--16 in all).
> 
> Scott