I have used this in the past with non-NHT systems. It is designed for the Evolution Series speakers though.
The X1 is the control center for the Evolution subwoofer systems. In addition to variable high and low pass filters to match subwoofers to satellites, the X1 features phase control and a separate gain control for the Low Frequency Effect channel. One of the X1's most unique features is the Boundary control, wich compensates for the proximity of the subwoofer enclosure to interior walls and allows you to tune the subwoofer to the room to maintain flat response. A look at the rear of the X1 shows maximum flexibility for virtually any type of conneciton, both differential balanced and unbalanced as well as the same auto-power circuitry found on the A1.