Single Rectifier noise problem.

[nicoroy123]

Hi guys, need some advise. I recently realized that I have an abnormal amount of buzz (kind of hum noise) when I raise the volume.

What could it be? Failed preamp or power amp tube?

I tried 2 guitars to be sure and same thing...

Or should I try a ground lift?

Any thoughts welcomed

Regards

 

[nicoroy123]

Here is an update...
I swapped all the tubes of the head with others I have in another amp. Same thing. I replaced all cables, same thing.

In modern mode, Output 10h00, Gain 1h00, , the noise really starts when the Master reaches around 8h30. At 9:00, it becomes unbearable.
If I switch to vintage or raw, the noise is still there but arrives later....

The noise is also there on the clean channel but definitely less evident.

I even tested with a ground lift. Same thing....

So at bedroom levels, everything is fine but as soon as I raise the volume, that hum/buzz become more problematic.

I am lost, what level of noise is acceptable on a rectifier?

Any help would be appreciated.
Regards

 

[primal]

hmm,

You mention the noise arrives later. Is it a slowly building hum?

I know that this can be an indication of unbalanced Power tubes. But you said you replaced all the tubes, or was that just the preamp tubes?

I had a problem on my Mark IV where there was a low hum that got worse the longer the amp was on. Got a new set of power tubes and it was gone!

 

[nicoroy123]

hmm,

You mention the noise arrives later. Is it a slowly building hum?

I know that this can be an indication of unbalanced Power tubes. But you said you replaced all the tubes, or was that just the preamp tubes?

I had a problem on my Mark IV where there was a low hum that got worse the longer the amp was on. Got a new set of power tubes and it was gone!

Hi, no the hum is constant. It simply increases while the volume increases.
I replaced all tubes, preamp and power.

Thanks