[sdiy] importance of Matched Transistor Pair

[jhaible]

>     Generally, what needs to be matched in matched pairs is the Vbe of the
> transistor.

Right. There are exceptions, however.
The transistors in Korg VCAs should be matched for the same signal
attenuation
at a certain base current. I just selected  48 2SC945's that way (can you
guess what my next project is ?), and I also checked for the beta of these
selected transistors, and it looks like selecting for beta is fine for the
Korg VCA selection.

For the envelope generators of the same project, I have to match groups of
13 transistors rather than pairs (4 cards with 12 ADSRs each ...)
These must be matched for Vbe.

Korg PS-synths have become so exceedingly expensive now that
building your own from scratch starts to make sense ...

Anybody knows of a source in Europe for 10k linear pull-pots ?

JH.