I am Fender, Marshall, Vox, and Peavey certified. But I handle repairs from all major manufactures.

I use only high quality replacement components, and often will recommend substitutes if I think the factory stock replacement will compromise performance/tone.

All repairs include a 10-point checklist:

1. Clean all of the potentiometers, jacks, and any contact switches.
2. Retention, and clean tube sockets.
3. Inspect filter, and bypass electrolytic capacitors. These have a recommended shelf life of five years. So that means these caps are 30-40 years old in vintage amps. Always an improvement in tone, and performance when these are replaced.
4. Inspect for cold or bad solder joints.
5. Hookup to dummy load, and check for output wattage, and abnormalities in the waveform.
6. Test tubes for emissions, static current draw, and dynamic mutual conductance.
7. Check all components to assure they are in spec.
8. Inspect all reverb, tremolo, speaker, and footswitch cables.
9. Bias output tubes.

and finally...

Perform listening test.