I did purchased toroid trans from farnell with 35-0-35 250VA. After passed through bridge rectifer, it access +- 100v which over LM3875 specification. Any one would like to help me on how to modify the PS to reduce the output volatage. Current I managed to reduce it with RC circuit BUT it have distortion when switch on & have some kind like air sound flow from left speaker to right speaker after 10sec switched on the amp.
Is correct, the calculation from 70*1.414 = 100v, which exceeded LM3875 specification which only allow to have 85v. I did include RC circuit in PS to reduce the voltage to 80v ( put the meter probe to + & - point to get 80v. But the sound have distortion like air sound flow from left speaker to right speaker. But the distortion went away IF the remove the RC circuit.
Steven Koay said:
There's an obvious option: you can build a regulator for your GC.
Some have reported good results from regulating, some say the GC sounded worst. Pedja has a nice regulator on his page.
You will have some heat, from the 7.5v x current on each regulator, but it could be worst.
Not everything is lost.
Carlos
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