Rectifiers

[AL1]

Which rectifiers can I use in a 1978 Silverface Princeton Reverb which came with a 5u4GB. I have a Gv4GA, GZ34 and 5y3GB.
Thanks.

[hasserl]

Did you mean a 5V4GA, not a GV4GA?

Any of these will plug into the socket and work. Both the GZ34 and the 5V4GA will result in an increase in B+ voltage and reduced sag, which may not be a good thing, especially if the amp still has the original filter cap can. Which if it does you should seriously consider having replaced. Care must be taken with either one of these two rectifiers that the B+ voltage does not exceed the maximum for the caps. The 5Y3GB will result in less B+ voltage and increased sag.

The bias should also be checked and adjusted as needed to keep the tubes operating in the correct range.

[KLB]

5V4 is usually a good substitute in a Princeton, plus it uses 1 amp less filament current than the 5U4, so your power tranny will run a little cooler.