Bottlehead transformer mounting

[ALL212]

Is the isolation of the main transformer for electrical or mechanical reasons?  I've torn apart some older amps and have never come across the isolation that BH puts into this.

Just wondering...

Thanks,
Aaron

[Paul Joppa]

Isolating the transformer core from the chassis and using one terminal to ground it to the safety ground reduces the leakage and magnetically-induced currents (a kind of ground loop) in the plate itself; this in turn reduces hum and/or buzz.

[ALL212]

Thanks Paul!