Archive of the former Yahoo!Groups mailing list: Yamaha CS80

....are really too busy because of their service job so they have no time to reply to anyone, could anybody give any answer to me about the pitch tracking on the filters? SInce I see no CVs or followers but I plainly hear a continuous tracking which is tied to the pitch ( simply switch octaves up-down and you'll realise it ) , can anybody explain me how this happens?
I talked some days ago with synth expert Rob Lebar from Alpha-Entek service repair in London UK and he explained me that

«This behaviour will occur on many analogue synths, with a resonant
filter setting. If the filter is not controlled by the bend, or is
controlled less than the VCO pitch.

As the pitch changes down, below the resonance it will be attenuated,
relative to the level when going through the peak.

It will happen, more distinctly, if a fixed high pass (or band pass)
filter is in use, the pitch will go below the pass band of the filter
and be attenuated or cut off.

So it is probably the action of the filters rather than the expression
circuit. »

As I told in the past, Juergen is right when he tells that the Expression circuit is not responsible for this behaviour, anyway if you play with any sound or select a preset like Organ1 (which has neither involving of velocity nor aftertouch) you can notice this effect, more if you raise the resonance to high levels.
If nobody has an answer, can you give me advices on how to contact an expert in order to understand this thing??
M

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