Triple rectifier PT problem

[creative]

I have problem with power transformer,after 30-60 minutes of playing it starts to vibrate,is very loud(not on speaker) and too hot to touch. only on spongy mode i don't hear any vibrations.
I need help!!!

 

[Gnarkill3k6]

What model do you have?
110v or 230v?
What is the rating of the fuse?

I don't suspect this is the problem since you're talking about the PT and not the OT... but is the head connected with a 'real' speaker cable to your cabinet/speakers?

 

[creative]

Triple rectifier european model(1998year) 230v,i use the same cable and box for all my heads.

 

[Gnarkill3k6]

Ok. That you use the same cable for everything you have does not say this is a proper speaker cable :wink: But I'm sure you checked this...

Have you ever looked inside your amp for loose screws on the PT?

What kind of power and rectifier tubes doe you use? Is the Bias switch in the correct setting? (not on EL34 mode with 6L6's?)

 

[creative]

I checked speaker cable and all tubes,bias setting,screws are not loose......first 20-30 minutes is working like new,and later when is hot i hear loud buzz sound from power transformer,only on spongy mode works normaly?

 

[Gnarkill3k6]

Spongy drops the internal voltages of the amp...
Are you sure your amp isn't "modded" by the previous owner? Maybe it has a Bias pot-mod or something and is set wrong.

Otherwise I advice you to record the problem in audio/video and contact Mesa directly about this.

 

[creative]

Solved!
JJ-GZ34 is not compatible with dual-triple rectifier(only on spongy mode),after 20-30 minutes in bold mode power tansformer is overheating. I returned original rectifier tubes and now is like new amp.

 

[Gnarkill3k6]

Wow! Thanks for sharing that ;-)
I have 3 Sovtek 5AR4/GZ34's in my triple... no problems so far btw.

 

[mesaboogie6L6]

Solved!
JJ-GZ34 is not compatible with dual-triple rectifier(only on spongy mode),after 20-30 minutes in bold mode power tansformer is overheating. I returned original rectifier tubes and now is like new amp.

Yes they are compatible, I use them in my 2 channel dual along with KT66 and KT88 in the bold mode or spongy, silicone diodes or rec tubes, all works well for me, I also use a 5 amp fuse instead of 4, of course wired 110. Maybe the GZ34's don't like the 230v! Glad you found the problem and all is ok now.

 

[APEMAN]

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