Here's a pic of the amp:
The only input is an XLR connection. It has no RCA inputs, but Mark includes an RCA to XLR adapter with the sub. It has no speaker level inputs, no phase control, no crossovers, or LPF/HPF, only a level control. It is expected that all those other functions reside in the receiver or pre/pro's Bass Management, which your receiver has. In your case, you would connect the RCA to XLR adapter to your receiver's Subwoofer 1output, then an XLR cable from the adapter to the sub.