Depending on which subwoofer you own, you will have different options for Power Controls.  These are Auto-On/Off: Eliminates the need for a manually operated power switch. Turns the subwoofer on whenever there is an input signal. If no input signal is sensed after a period of time the subwoofer will switch off automatically.

Trigger-On/Off: Allows the subwoofer’s power on/off to be controlled by components that have trigger outputs (Preamp/ Processor or A/V Receiver, etc.) using a 3.5mm cable.  It’s good to note that some products will work with only a mono cable, others with only stereo cables and some will work with either, so if you are having