#1
I bought my first tube amp (the vox ac30cc2) a little while ago. The first time I really cranked it for practicing with a band, the top boost channel gave out. Had to finish practice with the normal channel, but it worked fine. I was told it was likely bad tubes. I took time learning about it, before I tried to replace them, and by that time my normal channel was starting to cut out at high volumes or when I threw on heavier distortion like a fuzz.

I replaced all the preamp and power amp tubes. The normal channel then worked fine again, but the top boost is still just giving me a very quite signal. I turn it all the way up and you can just barely hear it with distortion on it, can't really hear it without the distortion. Any idea what it can be? What I could be missing? I'm pretty new to tube amps.

Thanks for any help.
#2
jeffben Get some contact cleaner (CAIG Deoxit D5) and try cleaning out the top boost inputs. Also spray some contact cleaner on the tube pins and try re-seating them. While you are at it, make sure the jacks are making proper contact with the guitar cable. Also, try a new rectifier as well. Lastly, be sure it is nothing silly causing the problem, like your cabling.

Tube amps can contain lethal voltages even when off and unplugged. Changing tubes does not really require contact with the internals but I think the CC2 requires you to take out the chassis for tube changes, so be careful.
Last edited by Will Lane at Mar 10, 2017,
#3
Will Lane I did try different guitars and cables.  I didn't know about the contact cleaner.  I will try those things, thanks for the suggestions.  I was at a loss.