Mesa 5Y3 rectifier tube death !!!!

[twally]

A little update to my fried tube. Last night I obtained some balls and stuck the suspect 5Y3 back in my amp to see if it really was the cause or if I might have a bad EL-84. I turned on the power and let the amp sit a few minutes (my standard procedure). Then I turned the standby switch on. Then, while looking at the back of the amp, I switched the amp from 30 watts to 5 watts. THe 5Y3 immediately started arcing. I shut the amp down before it could take out the fuse. So, the 5Y3 is definetly what I saw arcing a few weeks ago and took out my fuse.

It's a shame Mesa is having this problem. I feel they may be turning off potential buyers when they read Forums, such as this and get scared from the problems. Having said that, I won't trade my LSS for anything else out there. I will be carrying my spare 5Y3 when I gig.

 

[srvmac]

Yeh I have this mazda but not try yet.

The matter is it is a big tube so it is not compliant with the protection grid.

You have to remove it before installing this tube.

But definitely, even in France (so on EU version in 220v), this amp as a problem on circuit board and mesa repair service must apply a mod to correct it.

 

[212Mavguy]

bump for Thundersteel

 

[Thundersteel]

bump for Thundersteel

Thanks, 212Mavguy.


I just acquired a used LSS, serial # 3811. It has the Mesa 5Y3GT. It also has a 3 ASB fuse in it; I'll replace it with the correct 2ASB tomorrow.

My new Swart STR calls for a 5Y3 or 5AR4; but there is a JJ GZ34 installed. Question: Can I put the 5Y3 from the LSS in the Swart, and then safely put the GZ34 in the LSS?

Thanks for your help!

 

[212Mavguy]

Repeating ideas in the PM I sent you earlier today for the benefit of others:

5ar4/gz34 not recommended for LSS, too much increase in B+ voltage going to output tubes compared with output of 5y3. Vintage 5v4ga has increased voltage rise but not as much as 5ar4. LSS runs its power tubes pretty darn hot, they don't need any more juice than absolutely necessary. 5y3 in the Swart will probably do just fine there!