That doesn't sound right. EL84 tubes should have a faint orange glow from the filament and maybe some blue flouresence, but should not glow brightly. Is the large grey/black structure glowing bright red? If so you tube is about to go and could take out other parts of your amp. Get a new set of EL84s and try them out. I wouldn't play the amp as is.
If the new set of tubes doesn't cure the problem, I'd take it to a tech to get it sorted out.
tung
Originally Posted by guitartango