I have been repairing and building vacuum tube amplifiers professionally for over 10 years in Albuquerque, New Mexico. Hi-Fi audio has been my hobby and passion for over 20 years, during which time I have gained extensive experience with the most common amplifiers in the hi-fi as well as guitar markets such as vintage and modern Fender and Marshall amps and the range of vintage and modern Hi-Fi tube amps like Dynaco, Heathkit, McIntosh, and many more. 

The skills and knowledge of tube circuits applies to repairing any vacuum tube amp, as there is little fundamental difference in most standard designs.

As a former auto mechanic, who is NOT a rocket scientist (or labster) as we call them here in the land of the Labs....I take pride in my ability to FIND AND FIX THE PROBLEM, versus over-analyzing and trying to fix things that aren't broken with crazy notions of re-engineering something that was designed well to begin with.

I am NOT a guitar player, so my concentration when repairing such amps is not blurred by preferences in tone or other characteristics of major concern to guitar players. This is a PLUS when repairing guitar amps, as I am able from my experience to clarify and separate guitar players' expectations of these characteristics from the reality of what the amp was designed to do as well as impart a realistic expectation that tube amps are dynamic and no two are 100% alike.  

Here at our shop, we subscribe to "If it ain't broke, don't fix it.
I do maintain stock of common audio amplifier tubes such as 6L6, EL34, 6550/KT88, 6V6, EL84, 12AX7, and some rectifiers. I can order others and I do my best to compete
with online pricing. I also have access to all common tube amp replacement parts such as transformers and capacitors.

I generally stay away from solid state amplifiers, however I am willing to do basic repairs on solid state equipment  such as pot or jack replacement when the issue is externally obvious. I DO NOT do component level diagnostics on solid state equipment.
Also, I do NOT do tuner circuitry. No antique radios. I am willing to basic service on vintage tube and solid state receivers, but again, no diagnoses on solid state circuitry or tuner circuitry of any kind.
  NO CAR AUDIO AMPS!
No Mixers.
I generally stick to the realm of TUBE AMPLIFIERS and pre-amps, and I do that quite well.
Lastly, I ALSO DO speaker repairs. Re-foaming or re-coning is available, however often times the availability of parts is inhibiting.