Vintage Synth Repair

On Wednesday 26 March 2008 14:10, Philip wrote:
> Cool thanks guys! I did the mod today....makes a huge
> difference to the filters...they were a bit feeble
> before..now they sound great and wide open..
>
> The problem with strings attack thumping...well
> there's a pot you adjust called Strings VCA CVR to
> minimise it in the service manual but I have to say it
> doesn't do that much, it was in the optimal postion
> anyway. I did the same adjustment to the polysynth
> section and it did  improve the thumping in that
> section and quieten it down.
>
> So what cause the thumping then?

CVR = Control Voltage Reject

You don't want the control voltage showing up in the output of a signal 
processing circuit,  so things are supposed to be "balanced" to prevent that 
from happening.  Not having perfect parts,  they provide the adjustment in 
there to balance things out.

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ablest -- form of life in this section of space,  a critter that can
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