Challenger CH8 Modified PA Amplifier - Late '40s

Modified Challenger CH8 amplifier with original tubes: Preamp: 6SF5 + 6SJ7 Power: 6L6GA Rectifier: 5Y3 One volume and one tone knob, with a tone bypass option. Captures with the tone circuit bypassed have "TX" in the title. Otherwise, the tone circuit is on at 100%. Captures with a "+" in title employ a switchable cathode bypass capacitor from pin 5 on the 6SJ7 tube to ground. This increases the gain. I had a hard time getting the boosted and tone circuit bypassed tones to cooperate for the captures; the amp gets wild and fuzzy and I ran into errors while processing the files. I'll continue to try. The sweetest tone is probably the V100 T100 (not bypassed/not boosted) capture- warm with just the right amount of breakup. Run through the 16ohm output into a Marshall 4x12 with Celestion G12T-75 speakers. Captured with SM57 and SM58 on the edge of the cone. Signal chain: Focusrite Scarlett 2i2 > Palmer Trave > CH8> Marshall 4x12 > SM57/SM58 > Scarlett 2i2