Just received my new JCM 800 2203 head with a new vintage 1960 av cabinet. Hooked it up and turned the power on standby. Very noticeable humming sound coming from inside the head. Is this normal? I have a early 90's JCM 900 that never has made any sounds on standby or powered up fully. Can I get some advice before I decide to send it back and go with something else?

thanks much!

Hi there, guys 

I’m new to the forum and new to valve amps. In fact, I’ve just purchased my first valve amp: a brand new JCM 800 2203 reissue.

Running through a 1960av and a Rivera Rock Crusher attenuator and it sounds awesome - except for these damn so called ghost notes (just learned about them) that only happen when I set the master volume at higher values (above 6.5 or 7). It also only seems audible in higher pitches around the 12 fret.

Reading a lot about filter caps and stuff. But it’s a brand new amp and I still have warranty. So that’s not the case for trying to fix it myself.

My question is: should I assume it’s “normal” and keep my amp? If that’s the case, how can I crank it (and get that  beautiful power section overdrive) and minimize those annoying ghost notes? Is electric grounding improvement / adding a power filter of any good?

Or you guys think I should go to Marshall assistance and ask for a replacement?

Thank you very much,

Any help appreciated,