PLEASE take the time to poke around on this site for a while:
http://www.amptone.com/
Maybe if you read the same story from enough different people, it will start to sink in. There's a review of a studio amp that will use one or two of just about any kind of tube(s), and sounds really good.
That particular amp is meant for use by engineers, in a studio, but there are articles on that site about other designs that would be more suitable for stage use. I'm in the (slow) process of putting together a single-tube power amp to be driven by my Peavey Rock Master preamp.
I chose the 6AQ5A because its a miniature (the same size as a 12AX7A preamp tube), version of the 6V6 used in the original Fender Champions. The specs on the two tubes are nearly identical, so I can change to a 6V6 later, if it turns out that there is a difference in the sound. I also wanted a 5-Watt output so that it would be loud enough to get real acoustic feedback from my guitar. The Fender Champ has long been a popular choice for studio recording, either mic'ed or running DI tapped off the output. I've got a couple of old 12" speakers from a junked film projector that I might use instead of buying a pair of 8-inchers.
Something that really caught my attention was the fact that you have to cut the power to the speakers by a factor of [u]ten[/u] to reduce the apparent volume by [u]half[/u]!
That means a [u]5 Watt amp[/u] will produce [u]half[/u] of the sound pressure level of a [u]50 Watt amp[/u] driving the [u]same speakers[/u]! In my line of work, I should have realized that, but frankly I never thought about it. I now have two big Ampeg combo amps, and a pair of 4x10 cabs, that I can't really use unless I get a gig at a stadium! (O Yeah, that'll happen!) :rolleyes: