Whining amp noise - clip included inside

[farren]

Hello, first post here... I recently bought a Mark V head and Stiletto 4x12. This is my first tube amp in a very long time, and my first ever of this magnitude. I was hoping to be able to record with it soon, but it looks like it may not happen in my house.

Regardless of what wall outlet I plug into (or power strip) and regardless of other appliances are on in my house (I've experimented with turning off everything in the house except amp at the breaker), I get a horrible whine/whimpering sound that isn't noticeable at low volumes but becomes very noticeable if I turn up the output to reasonable levels around 9:00. This is regardless of pre-FX, FX in the chain, or bypassing the loop, it happens on any channel, any cabinet, any speaker cable, etc., and the guitar has nothing to do with it as it also happens with guitar volume at 0 or muted by a TU-2 in the chain. You see where I'm going with this...

Honestly, I think it has nothing to do with the amp at all, but I'm posting here anyway because I have a Mark V and there are likely experienced people here who have heard this horrible sound before. I'm afraid I simply have dirty power.

Anyway, here's a clip. It was recorded close-mic'd to the cab with an SM58. The amp is on channel 3 with fairly high gain and the aforementioned output setting. The first 10 seconds are me setting up the mic which I didn't bother to edit out for reference, and the last few seconds are me moving away to stop the recording. The whine comes and goes.

amp noise - 9.06MB

Does this sound like the kind of noise that only a balanced power supply or voltage regulator can fix? I'm confident a cheap Furman wouldn't do a thing in this situation. I can't exactly afford to put down $1500+ on balanced power right now, though. Is there anything else it could be? I believe I've exhausted all other possibilities :/

 

[Barry]

That almost has to be a preamp tube .take off the tube covers and tap on the tubes one at a time with a pencil when the problem starts . have you seen the new trouble shooting video Mesa did recently ? Its very helpful . Check out the blog on the mesa site .

 

[farren]

You nailed it. Sounds like I really assumed the worst! Looks like it's the V1 12AX7 after watching that video. I'll call Mesa Monday since it's still under warranty. Thanks!

 

[farren]

Well, I got my replacement tube and swapped it with each original tube. Same problem. It was strange--when I called tech support, the guy I spoke to (wish I could remember his name) seemed to think, before I even really had a chance to describe the sound recorded above, that it was likely a wiring fault and would require factory repair. This makes me suspect they had bad wiring/QA for a certain sequence of Mark Vs made over the summer as he made the wiring assertion after looking up my registration info and said they'd had a couple mis-wired Mark Vs come back to the factory for repair... My amp's serial is 34xx and was bought in early July. I haven't read anything about similar problems with other Mark Vs from this time, though I'm still looking around. I'm going to try it in a third house, and failing that, it looks like I'll be sending it back to the factory

How long do Mesas usually take for factory repair?

 

[jb's 52]

Since you got a "good tube" try in V7 as well. I think that's
the only other pre-amp tube that affects all channels.
Someone, please correct me if that's wrong.