Power Tubes... Can they cause volume (power) loss as they age?

[Ch0jin]

Yeah wow is right! Thanks heaps Tung! I have no idea what the original tubes were (apart from the fact they were 6L6's), as I didn't really check before they died and were replaced with those Sovteks by the store.

If I can ask another question

How do I avoid buying 5881's labelled as 6L6's?

I wasn't planning on going NOS as I was going to save that cash for the tubes in the JTM45 I'm building. Aside from the suggestions you have already offered, I've heard JJ's sound good in this amp (all the way through). Any thoughts?

And thanks again for the read. I'm amazed you got all that from my pic which was designed to be more "arty" than "informative"

[tunghaichuan***]

Yeah wow is right! Thanks heaps Tung! I have no idea what the original tubes were (apart from the fact they were 6L6's), as I didn't really check before they died and were replaced with those Sovteks by the store.

If I can ask another question

How do I avoid buying 5881's labelled as 6L6's?

I wasn't planning on going NOS as I was going to save that cash for the tubes in the JTM45 I'm building. Aside from the suggestions you have already offered, I've heard JJ's sound good in this amp (all the way through). Any thoughts?

And thanks again for the read. I'm amazed you got all that from my pic which was designed to be more "arty" than "informative"

I don't know much about the history of Peavey amps, but I've heard of them coming with real NOS Sylvania 6L6GCs.

It's hard to navigate tube nomenclature these days. Back in the good old days, if you bought a tube that said 6L6GC on it, it was a real 6L6GC spec'd tube. Now we have to deal with a lot of marketing BS and misdirection.

Obviously, I'd avoid anything that was labeled 5881. The Sovtek tube isn't even in the 6L6 family, and a real 5881 is only good for 23W vs 30W for a 6L6GC. I'd also avoid any of the Sovtek tubes in general.

If you look at this page:

http://thetubestore.com/6l65881types.html

The JJ, Winged C, and Svetlana are all real 6L6GC tubes. Not sure about the others. You'd also want to stay away from the 6L6GB as it is only a 23W tube like the real 5881.

I happen to like JJ tubes, love their EL84s, but have not tried their 6L6s. It looks like a real 6L6GC rated tube, so you may want to give it a try. I'd look for a vendor that does extensive testing and has a good return policy. Be aware that nothing made today will last nearly as long as NOS tubes will, so you will have to replace them more often.

Oh yeah, stay away from the run-of-the-mil 6П3С tubes. With out the -EB/EV on the end, it is a very different tube. The EV/EB tube is a ruggedized tube good for 10,000 hours according to the suffix. Without the suffix, the tube is a weak-*** 6L6-like tube. Probably equivalent to the 6L6-G, and only good for about 19W. Groove tubes used to relabel this as a 6V6 back in the 90s when there weren't any 6V6s being made.



The tube on the right is the 6П3С. The one in the middle is the 6П3С-EB aka Sovtek "5881."

Here's an even better picture of the 6П3С



You can see the designation marked on the tube. Avoid these at all costs.

Good luck and let us know how it all shakes out.