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Hey guys,
Really nice forum you have here!
I have a Marshall TSL100 having problems only in the crunch/lead channels. Low volume and low distortion in both. Clean channel is noticeably much louder and distorts almost the same as the other channels all at full gain/volume. This is clearly a preamp problem but I cannot figure it out.
All plate voltages are ok, I've measured everything. First I thought V1 was the problem since the plate at pin 6 is only at 170V but since the plate resistor is 220k in my amp I guess this voltage is pretty expected.
I followed the rest of the amp and noticed that the resistor R33 (100k) was measuring 40 approximately ohm. I cutted one of its pins and measured it and I figured it was actually ok, measuring 100k. Transistors TR1 and TR2 near V2 measure 40 and 70 ohm from drain to source. So, do you think this might be the source of the problem?? I'm almost losing my faith...
You can see the schematic in http://www.drtube.com/schematics/mar...03)%20iss7.pdf
Thank you.
Really nice forum you have here!
I have a Marshall TSL100 having problems only in the crunch/lead channels. Low volume and low distortion in both. Clean channel is noticeably much louder and distorts almost the same as the other channels all at full gain/volume. This is clearly a preamp problem but I cannot figure it out.
All plate voltages are ok, I've measured everything. First I thought V1 was the problem since the plate at pin 6 is only at 170V but since the plate resistor is 220k in my amp I guess this voltage is pretty expected.
I followed the rest of the amp and noticed that the resistor R33 (100k) was measuring 40 approximately ohm. I cutted one of its pins and measured it and I figured it was actually ok, measuring 100k. Transistors TR1 and TR2 near V2 measure 40 and 70 ohm from drain to source. So, do you think this might be the source of the problem?? I'm almost losing my faith...
You can see the schematic in http://www.drtube.com/schematics/mar...03)%20iss7.pdf
Thank you.