Question about 5U4G's

[Jmcthe3rd]

I've searched and couldn't find the answer. I have a Triple Rectifier that I use in the rectifier mode. How long due the 5U4G's last? Also how do you tell if they are going bad and need to be replaced?

Thanks.
James

 

[94Tremoverb]

Rectifier tubes seem to last until they fail, and work just the same until then - not like power tubes which wear out and lose performance slowly.

Testing them is easy: pull two, and leave one in. Run the amp at low volume in Tube Rectifier mode - if the amp works, the tube is OK. Repeat with the other two tubes. It's fine to run with just one rectifier tube as long as you don't crank the amp above low volume.