Velodyne and SVS subs absolutely WILL NOT allow mulitple interconnects that work at the same time. I have been through that with the technicians at both companies. Only one of the connections funcitons, in a distinct heirarchy, at any one time.
Specifically what is being asked here is can he use this for LFE and stereo with seperate connections for both, that will both work. That takes a specific set up in the amp/crossover network that not many subs have.
I don't see that Polk does that either. In fact going through the manuals of the DSW's both Micro Pro and Pro it states, " CONNECTING THE SUBWOOFER TO
THE SYSTEMHOOKUP OPTIONS
IMPORTANT NOTE: USE ONLY ONE OF THESE OPTIONS.
NEVER COMBINE HOOKUP OPTIONS"
I have never seen or heard of Epik, but since their website does not have manuals, and states a manual does not come with the sub (????), I'm not sure how those work. If that sub is not really set up to work that way, and you have it hooked up with multiple interonnects, it potentially could cause competing signals that cold damage the sub.
Be very careful which subs will do this, and what you pay for them. I have owned many a Velodyne, and a couple of SVS (great subs, super musical and great value), JL Audio, Sunfire, Def Tech, Rel (my fav musical sub).......
Only the Def Tech Supercubes and Rel's have had this optoin that I have seen. Call the companies and talk to the Tech's before you buy any sub that you want this optoin on.