loosing treble...

[littleguitar]

Hi, my MK IV is loosing his treble on R 2 and R 3 even with treble cranked and 6600 hz slider up !!!

R 1 seems ok, I try to change V1,V2, V3 and V4 and nothing's better

If someone could help me :mrgreen:

 

[Platypus]

How old are your power tubes?

 

[littleguitar]

something like one year but I've never push the amp "too hard" !

And I have no problem with channel 1...

 

[sparklesmcgraw]

Change ALL the power tubes. First option for finding the cure

 

[littleguitar]

i've changed the inner pair, it was the problem :mrgreen: