Widowmaker Amps & Isolation Transformers

[The Dude]

That could be, but if so, I'm not sure it's the right application of code. A karaoke machine requires the user to hold a microphone which is probably tied to chassis ground. I would think it would be a good idea to have an earthed chassis. Of course, that involves some speculation without seeing a schematic.

[g1]

Cordless mic?

[The Dude]

... or maybe some cheap plastic mic they supply with the unit.