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Tube Amp - Output Power Fuse Protection

The question is why do some manufactures of tube amps ,not have protection for the output stage of the amplifiers?
I have been auditioning some tube integrated amps that did not have any kind of fuse protection for the output stage of the amplifier.

I was in front of one amp when an EL34 tube flashed and knocked out the left channel. It blew out an output resistor , which has to be replaced to restore the amp. A simple fuse in the plate circuit would have protected the amp and with a new fuse , restored service. Instead , one would have to take the amp to a local repair shop , or have it shipped if not local.

Is this a common practice of manufactures to not have protection? Is it worth purchasing an amp that does not offer protection?

As we all know , it can be fun not to use protection , but sooner , or later it will cost you! One way or the other!
timo62

Showing 3 responses by grannyring

grannyring's avatar
grannyring
6,436 posts
 
Simple. Fuses sound like crap! Forget them and do not use them anywhere
if you want your gear to sound great! Ha!

A circuit breaker on/off switch is the way to go and no fuse at output. I
bypass them in digital gear with never an issue.

They really do sound awful in all honesty.
grannyring's avatar
grannyring
6,436 posts
 
It comes down to sound quality vs. risk of repair. If one does not like the "risk" involved, then buy an amp with a fuse at the output. We do have choices.

I and others bypass fuses and even place copper lugs in the fuse holder. I have not had one issue with this practice, but I am also able to fix any possible issue so for me the "risk" is not big.

I think it is reasonable to leave the fuse out as do others. So it is very subjective and linked to our risk & reward makeup with gear.
grannyring's avatar
grannyring
6,436 posts
 
Great points Upscale. I agree 100% with running tubes at 65%!
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