62 Ac30 Distorting :(

[rickjagger]

Hey everyone any help would be greatly appreciated!

I have a 62 non top boost ac30 which has started distorting when it should be clean.
I use the amp every night and it seems to be gettin worse and worse.
Ive replaced all the tubes and even put some new speakers in but this hasnt helped.

Thanks!!!

[Wakculloch]

Does this happen on all inputs? Is it built with the carbon comp resistors? If you can get some voltage readings that will help.

[bluesfreak]

If the amp hasn't gotten a cap job since it was built it might be worth to do it now.
Also check the cathode bypass cap near the 50 Ohm cathode resistor, it tens to dry out quick and causes problems...

[Bruce / Mission Amps]

If the amp hasn't gotten a cap job since it was built it might be worth to do it now.
Also check the cathode bypass cap near the 50 Ohm cathode resistor, it tens to dry out quick and causes problems...

Cap job...good start.
Yes, replace the bypass cap and change the cathode biasing resistor to a 68 ohm resistor.
These vintage VOX amps end up running high plate voltages in the USA at 122vac-126vac.
Many times in the past, I have lifted the power transformer's high voltage center tap and used a couple 5w 9v-12v zener diodes in series to lower the B+ a bit. You should be able to mount a terminal strip next to the power tranny in the chassis to do this.