5e3 hard on tubes?

[darefugee]

Hey guys,

I've read a couple of times that 5e3's are hard on output tubes and I'm wondering if any of you have first-hand experience with them eating 6V6's at an unusual rate.

I've built a couple 5e3 clones, one for me and one for my professional guitar playing buddy. They sound wonderful, but I don't play enough to torture-test them. My buddy wants to gig with his so I'd like to know what to expect.

[dorrisant]

If you use JJ 6v6s you shouldn't have to worry at all... Look at the JJ datasheet. That's all I've ever used in mine.

Tony

[darefugee]

Thanks, I know how to fix it. JJ 6v6s are bullet-proof.

But again, my question is does anyone have experience with their 5e3 or 5e3 clone being hard on output tubes? I don't want to replace old-stock tubes with new JJ tubes unless it's necessary.

[martin manning]

5E3 plate voltage isn't too high, so as long as the bias is reasonable there shouldn't be any issue there. Old production 6V6GT tubes should be at least as tough as any modern 6V6.

[darefugee]

Thanks Martin. My 5e3 clones are built using Hammond AO-29 transformers and you're right, the plate voltage and bias are very reasonable. I also used the tubes which came with the Hammond amps because they test good and sound really nice. Don't want to replace them unless it's necessary. My pro buddy is all about tone, and I'm pretty sure he'll want to keep old-stock tubes in there if possible. I'll probably give him an extra set of JJ's just in case, but I want to be able to tell him what to expect.

[Stevem]

If you wanted to be a stickler about it the output tubes could use a 350 screen grid resistor?

[billyz]

5e3's are not hard on tubes, actually the opposite is true. They do lose the output transformer. The only time they would be hard on tubes is if the cathode bypass cap fails. I actually ran one with silicon diodes in place of the 5y3 for years , never lost a tube. I did replace the ot though. Of course the filters were replaced.