Turn on, turn off the appliance, low-frequency hum: Listen & Download Turn on, turn off the appliance, .mp3 Error! Change your browser, please! ⇓ Download Movement, Low frequency electric drone ⚠ Low frequency rumble ⚠ Electricity, Current, discharge ⚠ Low Frequency Electric Drone ⚠ Button click ⚠ Wall switch ⚠ Switch ⚠ Multichannel switch ⚠ Electric transformer ⚠ Jacob’s ladder, Electric discharges ⚠ Turn off the appliance,, Turn on ⚠ Electric sparks ⚠ ★★★★★