It is often the case that electric hum at a venue is picked up via a ground loop.

There came a deep, electric hum and click.

Somewhere in the distance a faint electric hum could be heard.

There was an electric hum along the outer fence.

The car started off with an electric hum.

Their power created an electric hum in the air.

I remember between us the steady electric hum of tense, angry silences.

Not a sound except for the tiniest electric hum that came from somewhere.

The almost imperceptible electric hum inside the apartment suddenly stopped.

She stood very still inside the electric hum his hands created, not asking any questions, not moving at all.