Re: How to silence an EL Wire AC Inverter?
The noise emitters in the EL inverter are the wires in the transformer (it doesn't matter how tightly you wrap them, there's always a little room for them to move) and a minor piezoelectric effect in any ceramic capacitors used in the circuit.
Active cancellation (playing the same sound 180 degrees out of phase) is theoretically possible, but the phasing is critical. If you get it wrong, you double the noise rather than cancelling it.
The easiest solution is just to put the inverter into something that mutes sound, like a neoprene cover.