To the right of the volume control you will notice the Lowpass adjustment. This allows the user to set which frequencies will be passed to the subwoofer and what point frequencies will be set to move on the main or satellite speakers.
Moving right you will see the power switch. This switch can be used as a typical on/off switch or it can be set in the auto position. The Auto/On switch sets the Polk PSW10 up to automatically activate when it senses a low frequency signal. Above the power switch is the power on indicator light. It will be green if the subwoofer is active.
To the right of the auto-on switch is the Phase switch. This enables the user to match the in/out motion of the subwoofer speaker to the in/out motion of the rest of the speakers. This will result in bettter bass performance if set properly.
At the farthest right of the photo, is where the standard RCA line level inputs are. These inputs is where you connect the subwoofer output on your home theater receiver to (usually just labeled Subwoofer Out or Subwoofer Pre-out on a Receiver) or a stereo preamp output.
Below the controls described in the above paragraphs are the Speaker Level Connections. These connections are used if a line level connection is not possible. Using these connections on the Polk PSW10, the user can connect the subwoofer to a set of main speakers. Using the lowpass adjustment, the user can determine what frequencies the Polk PSW10 will use and what frequencies it will pass onto the main speakers.