Any Ideas?!?!?!

Lee Bob

New member
I just blew the fuse in my Mesa Boogie Tremoverb combo for the second time in about 6 weeks. The first time it was a blown rectifier tube the caused the fuse to blow. I don't have a second fuse on hand so I can't check right now if it is the same problem. However, if it is what could be the possibly larger problem behind this?
I am running JJ E34L power tubes and JJ GZ34 rectifier tubes. However, I'm only running 2 power tubes and 1 recto tube (as opposed to the standard 4 and 2) at the recommendation of a Mesa tech to reduce the wattage from 100 to 50.

Any ideas on what could be the problem? Should I just run the standard 4 power tubes and 2 recto tubes.
 
Re: Any Ideas?!?!?!

First, E-34L's are 10% hotter than EL-34's, which means the preset bias in the Mesa isn't a perfect bias for them.

Second, with a choice between silicon and tube rectification, I don't think you can pull out one of the two Rec tubes. I'm not sure, but aren't those amps supposed to use 5U4G rectifier tubes, not GZ-34?

Also, when you pull out two power tubes, you've also got to set your ohms selector at half what your speaker cab is. Cab 16 = Amp 8 Cab 8 = Amp 4

If I were you, I'd put 4 JJ EL-34's or 6L6's, and put both of the proper Rec tubes back in. Just use the amp at half power.......it has that feature, right?
 
Re: Any Ideas?!?!?!

Gearjoneser said:
First, E-34L's are 10% hotter than EL-34's, which means the preset bias in the Mesa isn't a perfect bias for them.

I had the same problem with EH EL34's a few weeks ago.

Gearjoneser said:
I'm not sure, but aren't those amps supposed to use 5U4G rectifier tubes, not GZ-34?

Actually they can use the GZ34's. They just come stock with 5U4's. Bob at Eurotubes sells only GZ34;s for Recto's.

Gearjoneser said:
Also, when you pull out two power tubes, you've also got to set your ohms selector at half what your speaker cab is. Cab 16 = Amp 8 Cab 8 = Amp 4

I was aware of this and have done that.

Thanks for your insight though GJ.
 
Re: Any Ideas?!?!?!

I remember someone here about half a year ago was having the same sort of problems, due to GZ-34's. I think the solution to your problem is to put 2 5U4G's in the amp, since Mesa designed it that way. I don't know all the info, but I think Bob's steered a few guys the wrong way, and it resulted in Mesa amp damage.
 
Re: Any Ideas?!?!?!

I would try the 5U4G rectifier tubes first. Also, the Tremoverbs sound great, they are notorious for breaking down. One of the biggies are the screen grid resistors...That doesn't sound like your problem, but you might want to be careful or even get it checked up by a Boogie authorized tech in the future.

MJ
 
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