Hi, I have an EP500 sub hooked up to an Outlaw 990 via XLR connection. I have a second sub and wanted to hook up to the line out coax of the EP500.(since the second sub has no XLR connection). Can I do this? I tried but get no signal to the second sub. Will the Ep500 send a signal out the line out connection with the XLR in in hooked up? Thanks for any information you can provide me.