"Wayne" wrote in message
...
This may be a little OT, but it still has to do with caps.

I've got a Fender '65 Twin thats got old GE paper electrolytics in the B+
circuit.
Most are 20uf @ 450 volts. I'm a relunctant to replace those with NOS for
the
obvious reasons the NOS probably are not gonna be an improvement over
whats in
there now.

Correct. They're likely to be just as bad, maybe worse.

First. Is it advisable to replace with something else, since technology
changes and this is 40 year old design.?

Second, I'm having problems finding new replacements because of the 450v
requirement.

Third, should I also replace all those .1mfd and .047mfd while I'm at it
and
with what?

BTW, I'm really not interested in changing the "sound" of the Twin. It's
a
great amp as is!!! Just wanting to clean up some of the hum, etc.

The problem is, you *are* going to change the sound. Why? Because as the
capacitors have aged, you've gotten used to the sound of an amp with bad,
saggy, worn out supply caps. When you replace them with caps that actually
do what they're supposed to, you'll hear a different sound, probably pretty
close to what the amp sounded like when it was new (discounting the changes
in the speakers, of course).

So you're going to change it; sorry, that's just the way life is sometimes.
You can get new caps various places; Panasonic makes a 33uF 450V one (TSUP
series), and they have some other TSxx 450V series with higher temperature
ratings, which will improve reliability, but they're all bigger than 33uF. I
would like that (nice tight bass) but it'll further change the sound, and
you might not like it. Panasonic caps are available at Digi-Key
(www.digikey.com).

Or you can get something a lot closer to what Fender used from Antique
Electronic Supply (www.tubesandmore.com). I'd stay away from the NOS stuff,
though; as you noted, it probably won't clean your hum up.

Peace,
Paul