01-05-2017, 08:45 AM
You really don't want to go more than 10 uF for the first filter cap C104, because its value affects the voltage output. If you have residual hum, you can increase the value of the second filter cap C103 within reason, which will reduce hum without affecting the voltage. I usually go to a 22uF to 33 uf electrolytic for the second cap.
I typically use the 10 uF polypropylene for the first filter, as it is still small enough to fit within the original cap can. That's the cap subject to the most stress from the high ripple current. The remaining filters see very little ripple, so electrolytics are fine there.
Have you adjusted the hum pot 106? This sets the balance between the the two 6A3 tubes and should be set for minimum hum.
I typically use the 10 uF polypropylene for the first filter, as it is still small enough to fit within the original cap can. That's the cap subject to the most stress from the high ripple current. The remaining filters see very little ripple, so electrolytics are fine there.
Have you adjusted the hum pot 106? This sets the balance between the the two 6A3 tubes and should be set for minimum hum.
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