"Jim Lesurf"


Erm... IIRC the Quad 34 uses a special version of the Alps 40mm detent
stepped pot/attenuator. I doubt you will find one from Maplin for 2-3
quid!
( If so, it is about time I sent them an order for a dozen. :-) )



** The Quad 34 does not use a stepped attenuator.

http://www.geocities.com/quad_esl63/...atic/pre34.jpg

The Volume control ( RV1a and RV1b ) is wired in the inverting feedback loop
around ICs 9 and 10.

The gain characteristic of this arrangement is quite unlike that of a simple
attenuator as it effectively converts a linear curve pot to log.

So I strongly suspect RV1 is a dual gang, continuous track, *linear* pot of
about 10 kohms.

Gives a lost cost volume control with predictable log curve and good
tracking.

PW would not be able to resist it.




...... Phil