In article ,
Jim Lesurf wrote:
I was more hoping someone could come up with why some of these
crossovers squawk, but some not.

I guess that we can't say much more than the obvious. i.e. that
something is different between examples of amps and crossovers/speakers!
Not exactly news for you. :-/

I've never seen an AM8/16 so have no idea what changes the BBC people
may have made. I can't tell if the 'quawk' is due to a protection
circuit rattling on and off, bursts of RF instability, or what. Might be
fixable by a bigger output inductor or a cap in just the right place.
But where?...

Thought I'd made it fairly clear. If you remove the power to the crossover
PCB while leaving the amp powered up, you get the squawk. Leave the power
off that PCB, and the Quad part powers up and off normally.

Ideally, you'd be best asking in some place were ancient BBC engineers
are listening. But again, I'm not sure where to suggest!

Finding one who knows the design intimately is the problem. As an aside,
noticed the Keith Snooks site seems to have disappeared too. Everyone is
getting old.

--
*All those who believe in psychokinesis, raise my hand *

Dave Plowman London SW
To e-mail, change noise into sound.