On 13/03/2015 21:46, Don Pearce wrote:
On Fri, 13 Mar 2015 21:02:25 +0000, RJH wrote:

My 20 year old Rose valve preamp has started making a 'whooshing' sound,
varies in intensity, with a steady rush of background hiss. Might it be
the valves? Everything lights up, and I've had the back off and all
looks in order.

For now, I'm using an older(er) NAD 3020 integrated amp in preamp mode.
It works fine, but sounds 'soft' by comparison with the Rose (when it
worked) - 'smooth' treble and a quite overblown bass. I did notice this:

https://flic.kr/p/rjtZuf

when I got it out the cupboard - but I'm guessing all that mess is glue?
Anything look untoward?

That brown stuff is glue - cheaper than proper clamps I suppose. The
symptoms do sound very much like bad caps.

Audio amplifiers definitely should not have a "sound" though. They are
supposed to be transparent apart from making things louder. If I were
you I would ditch all the suspicious old stuff and simply buy
something new.


Yes, thanks. I think I might keep the NAD and see about fixing the caps.
Seem to be a number of guides online, and I've not much to lose.


--
Cheers, Rob