[sdiy] VCA distortion - bad

[harrybissell]

This is with the topology where the negative rail of the OTA is varied with
the CV. I saw this in a Craig Anderton design (and also in Electronotes as you
mentioned)... but I have never tried it.

It certainly saves having to use a PNP current source to drive the Iabc pin
(referenced to the negative rail) but I always wondered if it would affect the
headroom.

So anyone tried this and vouch for it ???

H^) harry

Michael Ruberto wrote:

> I was wondering if it's possible that the op-amps I am using might have too
> hot an output. in the original schematic Bernie specifies a LF353 and I am
> using a TL072. could there be enough of a difference in the current sinking
> ability between these devices to cause the overdrive?
>
> ~M
>
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