03-19-2019, 01:16 PM
I do not think changing speaker could possibly help.
Some very low level of hum is present on many DC-DC sets.
There was once, about 2 years ago, one chassis I did that had pretty pronounced hum, and I could never locate the source; I ended up lowering the output tube's input resistance where it was being picked up and it too care of most of it.
Sometimes it is a wire that runs where it shouldn't, like nearby the power path while being a part of some high impedance input.
A tracer would probably help locating the point where it starts.
Some very low level of hum is present on many DC-DC sets.
There was once, about 2 years ago, one chassis I did that had pretty pronounced hum, and I could never locate the source; I ended up lowering the output tube's input resistance where it was being picked up and it too care of most of it.
Sometimes it is a wire that runs where it shouldn't, like nearby the power path while being a part of some high impedance input.
A tracer would probably help locating the point where it starts.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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