What is wrong with my Herbert??

[Flo85]

Hello guys..I have a problem.
Since 2 weeks I hear a loud boom, when I enable my Herbert.
If i switch the Herbi into the standbymode and enable him again everything is normal.
Only at the first time he boomes

can someone help me?

 

[Duolos]

Does the amp play and sound right? Have you retubed it lately...? Sometimes tubes will make noise when they heat up and cool down when they are new. This noise is normal.

 

[Flo85]

I didn't change anything.
The tubes are 2 years old.
The problem comes over night.
It can be that the sound is à bit muddy.

 

[Hard&Heavy]

I could be wrong, but it sounds like tubes to me.

 

[steve_k]

1. Turn the master volume down
2. Flip Herbie from standby to run
3. Turn master volume to desired level
4. Let Herbie really boom now



Steve

 

[Flo85]

the question is why it was'nt like this right from the beginning?
SOmething must have changed.

 

[Duolos]

the question is why it was'nt like this right from the beginning?
SOmething must have changed.

Sounds like it is time to change tubes.

 

[Flo85]

The bang comes out of the box idependetly of the channel, which is enganged before turning on the power button.
Can the tubes anyway be the prob?

 

[Duolos]

It is impossible to fully advise without the amp on my workbench.

 

[Flo85]

ok

 

[steve_k]

If it is a preamp tube, it would have to be V1 or V3 since it appears across all channels. Pull V5 out and swap it for V1 then turn the amp on and see if this helps. If so, replace V1. Repeat for V3 if this is not it.

Steve