New Mesa Owner...Needs help

[GuitarGear]

Hi there, first post!
Recently bought a Nomad 55 combo 1x12 used on eBay, sounds great but have a issue. When turn up the volume little louder the Power Tubes (6L6) , begins to shake, and make annoying noise! . The tubes doesnt feel loose or sth. I think the problem is in the Tubes because the noise is like glass shaking.

Any one had that problem? Any suggestions?
Thanks for your help!

 

[mrd]

Sounds to me like tube microphonics. I'm fairly certain this is when a small piece of material is loose inside of the tube, causing it to interfere with the signal. You'll have to buy some new tubes... they aren't too expensive. You can get a matched pair of EL34s for about $42 I think.

 

[Platypus]

I'd also recommend a retube, if not just because the tubes are used and very often on their last legs anyway.

What is the sound like? Like rattling glass? Or is it the actual power tubes that rattle.. I couldn't tell from your post sorry. If there is a rectifier tube, try touching it gently while you play (obviously right when you turn your amp on, don't touch super hot tubes ).. sometimes rectifier tubes rattle like that.

Also what kind of room are you playing this in.. is it possible the noise you hear is stuff in your room rattling or reverberating? I don't mean to second guess you, just wanted to make sure the sound is actually coming from the amp itself.