The Andrews Amp Lab Experience

Andrews Amp Lab specializes in the repair and resurrection of Vintage Tube-Type guitar bass and PA amps, as well as many solid state and hybrid amps.

Customer Care

  • We keep a clean shop. You will not find your amp under a stack of parts and equipment.
  • You'll receive a detailed invoice showing what was done to your amp.
  • You will not be surprised by unexpected charges. All customers are contacted with estimates before extensive work is done.
  • Most repairs are completed in one to two weeks (fastest in summer).
  • We stand behind all of our work with a 90-day warranty.
  • We use only top quality parts.
  • E-mail is typically answered within 1 business day.

Thorough Diagnostics

Your amp will be diagnosed and evaluated with the most meticulous care. We don't just repair the obvious problem and put it back together with other problems still lurking. After giving your amp a thorough checkout and listening test, we contact you with a list of recommended work to achieve optimum tone and reliability. You can decide what you would like to have done.

Top Quality Components


All tubes are checked for shorts, microphonics, gain and sound quality (many on-line sellers don't actually listen to tubes before selling them). Then they are hot-tested under full power. Each tube is chosen for the best performance and reliability in your amp. We also check all of your existing tubes. If they pass all the electrical and listening tests, we don't replace them unless you specify that we do. If they fail our tests, I will let you know. See more about tubes here.


Carefully selected for best quality and reliability.


Most vintage amps (before the late 1970's) used carbon composition resistors because they was the only or only cost effective type available. Some techs or internet forum posters feel that they should still be used everywhere in repairs due to misconceptions about their effect on tone. We use carbon composition resistors where they work best and we use metal film, carbon film and flameproof metal oxide where they work best. The selection of resistor type has very little impact on the cost of amp repairs or mods. This choice is based on sound quality and is backed up by research and experience. Much has been written on this subject and you can read the details in Kevin O'Connor's books or R.G Keen's and Randall Aiken's web sites. To sum it up, there are only a few places in guitar amps where carbon comps are the best choice so we use them there for optimum tone. Metal film and metal oxide are much more accurate, reliable and quiet, so we use them throughout the rest of the amp.

Fantastic tone and reliability are our goals.

When your amp leaves our shop, will be as reliable as it can be and sound its best. You will probably hear great new tone you didn't even know your amp could produce! The deterioration of sound quality usually happens so slowly that often, it isn't noticed. Many customers report being surprised by the improvement in tone of their vintage amp after repair, often, they don't remember it ever sounding so good before.