So here are my old tubes, 6L6GC




I want to replace them with these, GT-6L6-GE... (will they be compatible?)



This post was edited by iOoze on Mar 7 2012 01:48am

UPDATE:

The spec sheet indicates that these tubes are certified safe for use with 500 VDC at the plates......

http://www.fender.com/community/forums/viewtopic.php?f=13&t=68608&p=814572#p814572
Your TRRI has 440 VDC -- thus, these tubes will be fine. I'd recommend measuring (and adjusting, if necessary) the idle bias when you install the new bottles.

This post was edited by iOoze on Mar 7 2012 02:18am

You can substitute 6V6's and 5881's for 6L6's. The 5881's are lower wattage and require re-biasing. However, you don't always have to re bias your amp. You mentioned messuring but most people don't have a plate voltage meter but the website www.thetubestore.com, you can send your old tubes to them and they can meassure your old tubes and send you the proper tubes to your amp. Granted your amp was set properly, mind you, it's sometimes subjective how you may want your amp to run.

These are the tubes I like if you like the warmer tones:

http://thetubestore.com/tad-6l6wgc.html

ty, hey... I just put in these new 6L6's, do tubes have a break in period? The signal breaks up when I turn loud.

Not really a break in period. They'll get softer and distort earlier as they tire from usage. As you turn loud you're increasing the amount of signal. Eventually it's going to break up but on that mighty twin of yours, you ought to be hurting before that happens. could be that the amp is biased to run hot which makes the tubes break up.

Alright, it went away within a few moments anyway. It just got really muddy and would cut out when I'd turn past four when I had first put them in.

but yes, the Twin is a mighty machine... might buy an attenuator actually....

This post was edited by iOoze on Mar 7 2012 01:43pm