Yes, my mistake, 138c is linear. I had a quick look and it is very
easy to put a jumper on it and then to get the offset function.
I'm pretty sure there was no jumper on it when I purchased it, dunno
why...

By the way, I searched on the Doepfer website and didn't see any
information regarding those jumpers (wanted to know the length between
the too things, I guess it's 2.5mm). Maybe I missed it, but if there
isn't any, that would be cool to mention it somewhere with a little
'how to' for noobs like me !

Cheers,
Max.

> The A-138c is available only with linear response (you probably mix

it up

> with A-138a/b). Potentiometers with dual exponential response

(symmetrical

> from the center position) are hard to find. We asked our manufacturer if
> this special response can be manufactured but they answered that

it's not

> possible (at least from them).
>
> Best wishes
> Dieter Doepfer