Bob the Tech Audio completed repair and restoration of this JBL SA600 amplifier, which came in with a partially disassembled power supply and a channel out. We completely rebuilt the power supply to replace the missing and remaining original filter capacitors. Once the supply was operating properly, we found the issue with one channel not passing a signal. We readily resolved this by replacing faulty driver and power transistors in that channel. We performed a complete re-cap of the preamplifier and amplifier boards. As a result, the amplifier is fully updated and able to run for years to come.
The unit arrived missing one of the main power supply filter capacitors. The other capacitors were original. Since there had apparently been a failure of one of the four, we replaced all four. Our approach was to use modern snap-in radial capacitors adapted to the chassis by using mounting brackets. Once the main filter capacitors and the first rectifier were installed, we were able to install the additional rectifiers and their filters. Once reinstalled the supply fits cleanly into the chassis.
We continued the restoration of the JBL SA600 by updating the electrolytic capacitors on the preamp and power amplifier boards.
We quickly isolated the issue with one channel to the driver / power transistors, identified replacements, and had the unit repaired. Performance tests show it’s performing well. Bob the Tech Audio provides repair and restoration for McIntosh and other fine amplifiers, including this JBL SA600. Contact Bob the Tech Audio for your service needs!
