I'm using my Marantz SC7s2 preamp connected to my Jeff Rowland amp through the XLR connections. I want to connect a Dynaudio 500 sub that has only one input.The preamp has 2 unbalanced outputs. I'm wondering if I can go from 1 pair of the outputs to the single input on the sub, using a y-cable. Will this cause any problems that anyone is aware of ?

Thanks
Joel