E04 - Blue-line 1973 (or so) Ampeg SVT: Quick Preamp Repair; Set the Bias, Balance, and Hum.

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This early SVT, owned by a back-line company, came in with channel one cutting out intermittently. They need the beast back ASAP. We quickly diagnose and repair the causes, and then bias the output, balance the 'push' wit' da 'pull,' set the hum balance, and ship it!
2:17 - Open the back
5:44 - Power-on and diagnostics
7:55 - Tear down
9:38 - PreAmp inspection
12:25 - Cleaning tube sockets and circuit board
13:20 to 14:30 - Messed up fade - kind of spacey though...
14:55 - Identifying the fault
15:25 - Discovery and repair
17:36 - Repair validation
19:56 - High temperature validation
21:11 - Tap testing and reassembly
24:40 - Bias adjustment
27:40 - Driver balance adjustment
30:20 - Hum balance adjustment
31:45 - Final testing
32:45 - Power output validation