[sants]

Sorry if this is a dumb question but I ask because someone told me it might not be good for the power tubes.
I am having my twin put into a head to run with 2x12 cab. I am using the amp and will not yet be pre-amping it and I will be standing the head on its side. I know Jerry did not have power tubes in his amp. Someone I talked with said that power tubes are meant to sit vertically but I never really heard this before. I know in mesa power amps the tube are horizontal so I take it it's fine. Just thought I would get the opinion of the board.

[JonnyBoy]

I don't think it matters at all how you place it. Maybe one kind of tube or another MIGHT have issue with gravity but I doubt it, or at least I haven't heard that. He just may assume that tubes have to hang since most do in amps. HiFi amps have the tubes upside down, plugged into the top, like an MC30. Jerry had his on the side and I have done the same without problems. My mosvalve has the 12ax7's on their sides, but secured with some silicone. That just doesn't sound true to me.

[Cmnaround]

I have a Mesa 20/20 tube power amp that is a single rackmount space and all the tubes are horizontal - I don't think it makes a difference. Doesn't look like there is anything special holding them in place - they are just plugged into their spots and hang "sideways" just fine without any droop or apparent excessive gravitational pull on them.

Good luck -

[bpg21]

If the power tubes (6L6's) are being used then it is best to not have your amp on it's side. Those suckers can run hot and if stacked on top of each other ( when amp is on it's side) ventilation is compromised due to the fact that heat rises. The pre amp tubes are less susesptible to this.

[bcresci]

Interesting question, because I had a problem at our gig this past weekend. I'm running a Trio, Valverb, into a Mosvavle power amp. The first two have tubes. Towards the end of the first set I stomped on a boost and...... nothing. The entire rig just quit on me.

I did have the case on it's side. But it was also not ventilated very well. For space reasons I was crammed back against a wall in a room that was hot as it is.

The next day, the rig was working fine again.

So would overheating cause one of the components to shut down? Which component of the three was the likely cause?

[SarnoMusicSolutions]

I'd wager that the Mosvalve's thermal protection kicked in from the heat. They naturally reset when cool. It's never a bad idea to put a computer fan behind a power amp, tube or transistor. Especially in the hot summer months. Just aim it at the tubes or the power transistors so the heat can dissipate. It makes a huge difference.

B

[strumminsix]

It's fine to do. Heat is always an issue and will be with tubes or solid state. Small fans a good thing!