Hi Roel

> sound as loud. I can tell you the A-131 is sometimes
> bearely audible, only when I turn the gain to 10, it
> sounds better, but doesn't come close to the volume of
> the A-130.

If you plug a VCO direct to the Audio in of both VCAs and you turn the Gain
on both to 10. You should hear a continous sound now. Has this sound the
same level on both VCAs
If yes, everything is ok.

The rest shows you what exponential really means: position 9 on the A131 is
equivalent to position 5 on the A130. Position 8 on the A131 is equivalent
to position 2.5 at the A130 and so on...

I personally don't like this characteristic and nearly never use the A131.
I am thinking about exchanging it against a A130.



BTW: The (service- )manual explains, that the CEM chip on the A130/131
contains two VCAs; only one of them is used. There is an multipin connector
on the pcb to connect the input and controlling electronics to the second
VCA. Does anyone here use this option

Florian