Restoring Gary Borden's Gibson GA-45

We've been on a bit of a hiatus lately working on other things - but we're back with something interesting!

Through a mutual friend (thanks Chris!) we recently met Gary Borden and he tried out our amps. He was impressed enough that he's planning to use them on some upcoming recording projects; more on this later.

Gary has a well-loved (and very well used) Gibson Maestro GA-45 that was in need of some restoration. We're not usually doing amp repairs, but we couldn't pass up the opportunity to bring a classic like this back to life, so we offered to help out.

The amp is an American classic from the late 1950's - well built and with a great vibe and patina.

ga45_rear.jpg

When we received the amp, some controls were seized and it would not produce audio. After some initial diagnostics we performed a number of much needed repairs, including:

  • Lubricating and cleaning all pots
  • Removing some "creative" speaker switching
  • Replacing the AC cord with a grounded, 3-wire cord
  • Rewiring the tremolo foot switch
  • Re-capping the power supply
  • Replacing the output tubes, rectifier tube and tremolo tube
  • Re-capping the tremolo circuit
  • Replacing all cathode bypass caps
  • Cleaning the speaker (a super "retro" University Model 6200)

With these repairs and a bunch of hand-selected NOS tubes, including a NOS 6SQ7 (thanks to George at Grandpa's Radio Shop), the amp works like a charm! It has a great clean sound and breaks into a beautiful overdrive when cranked. The tremolo also works great and definitely sounds vintage!

A big thanks to Gary for trusting us with such a great piece of classic gear; it was an absolute joy to work on!