18Watt.com

I know they sound great in guitars, but anyone used these in amps?

http://cgi.ebay.com/ws/eBayISAPI.dll?Vi ... 3816559639

I´d be very careful to put 40 years old used caps in an amp as most of them are likely leaky.

Adrian

Cou;d leaky caps do damage, or just not work?

They can definitely do damage! When used as coupling caps, DC will leak through and can affect the bias of the next stage. It can red-plate your power tubes faster than you can say "Ooops...".
You could always test for leakage bfore using them, but I've found it's best to shy away from used and NOS capacitors. The Black Beauties almost always leak. It's true that old caps look very cool and have a certain sound, but there are enough choices on the current market to enable us to find good-sounding, reliable, modern caps for our amps and not worry about when the next cap is going to fail.

Peace-
Ethan

D'oh! Ok, thanks for the info.

Anyone know if Sozo is making the repro mustards in values for the 18 watt yet?

They have a few like .022 and .01.

There is actually no such thing as an NOS capacitor. Caps dry out and go bad after 10 t0 20 years depending upon the design. Best to go with the highest quality new caps you can afford from makers like Mallory and Sprague.

Well that's with electolytic caps. There's nothing in a ceramic or foil cap to dry!
I've had plenty of good 40-50 year old caps that didn't drift or leak.

That's quite true of ceramic caps. I'd have to respectfully disagree about foil caps. many old foil caps use oiled paper as a dialectric and these caps can and do go bad. In some cases, really bad.
Several years ago I got some "Black Beauty" type caps from the late 50s which were the same type used in old McIntosh amplifiers. I later found out that all but one of those foil caps leaked, and roasted a pair of EL84s in the process. I have, however, used 50 year old ceramics that did not leak one bit. Very stable.
New, current production caps are definitely the way to go.

Now, Who's this making mustard cap repros?

Ethan

Do a google search for Sozo caps and you'll find their website and info including testimonials about their caps. Also there are a lot of threads about them sounding awesome on the PlexiPalace Marshall forum, mainly by guys who have used them very successfully in the Marshall re-issues.

Thanks. I went to their site and took a peek.
Expensive, but not crazy-expensive.
Anybody here had any experience with them?

Ethan

Thanks for the clarification on the caps, Ethan. I had no idea foil could dry out.
I've only heard great things about Sozo, though haven't used them myself.

Ah, yes. I didn't really clarify, did I? I should have excluded ceramics from my blanket statement. I guess I'm still seeing red from the Dallas guitar show at which some dealers were selling "NOS" can caps at ridiculous prices. You are so right. Nothing to dry out in ceramics.