I have no direct experience, but I see you have no replies. Many panel speaker owners like Vandersteen 2Wq subs with their speakers. I do own these subs, and feel they are fast, extended and powerful.
Subwoofers offer some or all of the following connection options:
RCA sub-out from preamp to line-level RCA input on sub
Speaker-wire out from amp to speaker level inputs on sub
The Vandersteen uses a dedicated pair of speaker cables that attach to your amp speaker outputs along with the speaker cables to your mains. An in-line filter or crossover is inserted between the preamp output and the amp input (one for each channel).
Subwoofers offer some or all of the following connection options:
RCA sub-out from preamp to line-level RCA input on sub
Speaker-wire out from amp to speaker level inputs on sub
The Vandersteen uses a dedicated pair of speaker cables that attach to your amp speaker outputs along with the speaker cables to your mains. An in-line filter or crossover is inserted between the preamp output and the amp input (one for each channel).