Fender Twin Reverb repair

 This Fender Twin Reverb 70's amp came in with some classic problems. It's a wonderful 2X12" combo tube amp but it had to be properly restored in order to sound great again. Here are some common issues I came across as I was restoring the amp:
Capacitors...
 The most common issue with these vintage amps is the capacitor ageing effect. All capacitors age but the large electrolytic capacitors of the power supply were almost dead in this case. You can easily spot a bad capacitor as it usually looks weird. You can also measure its capacitance with a DMM(digital multimeter).  
  Most defective electrolytic capacitors expand/bulge and you can see cracks on them. Sometimes, there's oil or other substances leaking out of an old capacitor that's gone bad. There could also be some burn marks on them. The twin reverb capacitors had many signs of wear as shown in the pictures below.
 Tubes
The other issue that's common to all tube amps are the tubes! Old "NOS"(new old stock) tubes are good when they actually work and there's still life in them... An old tube that's gone microphonic, bad and even dead in NOT a Nos tube... The 6L6s used on this twin were all defective and so we had to replace them with a modern matched set of tubes. We decided to use four platinum matched JJ 6L6s for the power amp and JJ 12AX7/12AT7s for the preamp. JJ tubes are made in Slovakia and they're good value tubes as they're quite affordable and still sound really good. Some tubes that are made in China can be defective sometimes but I never had issues with these European JJs.
 Speakers
 We also checked the speakers for signs of wear as the cone may be damaged. The twin reverb had no cone tears or anything but it only had one of the original 12" Oxford speakers on it.
 Grill and faceplate
The faceplate on this silver twin was worn out, so the owner bought a "blackface" style faceplate sticker. Placing a sticker faceplate on your amp is affordable, offers a new look and it's a totally reversible mod.
The grill was also worn. The grill is wrapped on a wooden mdf plate and the plate is attached to the amp cabinet with some velcro pads.
 Finale
 For the finale, the amp was properly biased and cleaned to look and sound nice again! It's a very nice clean sounding amp with treble to cut through any mix!

Here are some pictures: