In article , Woody
wrote:
"h.tees" wrote in message


I don't think that may necessarily be the case. Quad were quite good
with their circuit design, and if the volume pot interfaced to a high
impedence load then it may not be the pot as such circuits were not
prone to that type of noise.

Unless the unit has been badly mistreated I also have doubts that the pot
is to blame as they are quite high quality stepped attenuators. More likely
a poor connection or dud cap elsewhere.

I suspect the problem here is dried out and/or leaky electrolytic
capacitors. Clicks whilst playing are typical of capacitors that are
leaking and affecting d.c. bias conditions.

I also suspect something like that.

I would agree that crackles whilst playing are also typical of a volume
pot that has gone noisy, but it should not do it at minimum volume where
the pot wiper is effectively earthed.

The loss of one channel that plays when the mono button is pressed says
one pre-amp is not working. I had a Q33 which had plug-in circuit
boards: it is just possible that this unit may be of the same
construction and that the boards have become dislodged. It might be an
idea to get the lid off and see if this is the case - if it has plug-in
boards even remove them, clean the contacts if necessary and put them
back. It might just cure everything.

I'd also recommend that.

I am trying to recall if early 34s had their ICs in holders. If so,
something like that is a candidate.

Slainte,

Jim

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