Connecting a Second Sub Question

[lamont360]

I'm currently running a 7.1 system from a pioneer VSX 1019 AH-K receiver. It is currently sending the sub frequency to a single SVS PC-12 NSD. Eventually I will want to grab a second sub (probably another SVS) to help equalize the sound in the room. Since my receiver only has a single sub output, what is the usual protocol for setting up a 2nd sub? Do I buy a splitter and attach it to the receiver?

Any advice would be most helpful.

Thanks