I became the new owner of a Garnet Amp, a Rev-II that was not working. It was in decent shape but needed cleaning, new tubes, fixed speaker, and some pot cleaning. It now works fine and I really like the reverb sounds that it makes.
The speaker was fractured in some areas of the surround cone. This was repaired using some Varathane Diamond Wood Finish that was water based and some high grade paper tissue called silkspan from the model aircraft trade. Silkspan is a strong paper that works well when wet and is used to cover model aircraft wings and wood finish. It works fine with water based varathane and made for a durable flexible repair for this speaker. Sure I could have gone out and got a new speaker, but this one was not that far gone and was worth the test. It sounds normal now. The pre-amp 12ax7 tube failed, so that got replaced and one of the 6L6 tubes was very hot and then it zapped itself. I replaced both with a new set of 6L6 from Mesa. The pots were dry and got a squirt of electronics cleaner called Deoxit Fader F5 that improved all of them. Sounds improved, scratches went away and the controls freed up and feel like they work better.