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[email protected] palli...@gmail.com is offline
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Default Where does the hum come from?

Scott Dorsey wrote:
================

If unshielded speaker wire is used for line level connections, there will
be a hum.


** Certainly, but this can also happen with cheap RCA leads.

I found this out when repairing a Fender tube amp with a faulty reverb.
The connecting RCA leads were bad so I fitted a new pair that were the right length and had stubby plugs.
The result was buzzing noise and loud squealing if you turned up the reverb gain pot.

When cut open, the cable used was NOT co-axial !!
The ground wires just ran alongside the core in a tight bunch providing no ES shielding.

Soon as I fitted known, well shielded leads - all problems vanished.


...... Phil