Subwoofer & pre amp

I like JL Audio subwoofer, had F113 for a brief period and thought it was better than Rel B1 & Stadium I used to own.

I now have a pre amp with only 1 set of output; JL only takes line leve input and no speaker level input. Short of using a Y-adaptor which will degrade sound more or less, will I be better off getting a Velodyne DD or Rel again? Either one will be physically larger than JL whcih could be an issue.

This sub will be 30% music & 70% HT, I normally don't use sub for music but like to have that option.