07-09-2012, 07:20 AM
So, I just bought a set of power tubes about a month ago and at a gig this weekend, I noticed the "mini-fire" action goin on and pretty much no sound coming out of my amp. This troubles me, b/c it's the first time I've had to replace the tubes in well over a year and a half. This tells me that I've either gotten the wrong tube rating...which was '7' I believe...or the amp needs to be biased again and with that re-tubed also. I've read that these are self-biasing, but if this is the case, why are my tubes jacked in a month?! Advice?