The first tube amp I ever used was a Traynor Bassmaster (I still think it sounds like a fishing lure :) ) with a 2x12 cabinet. They were originally modelled on the Fender amps (same as early Marshalls), and soon developed a reputation for sound quality and road-worthy durability.

I've met some of the people that work at Yorkville. They are serious about building their gear for working professionals.