Not really digital…. (Subwoofer)

It is my experience that it is best to use the sub that the manufacturer intended to be used with your top speakers. Usually they are best balanced (both with driver placement if you use them stacked and crossover frequency) and will give the best overall sound as a set. That is not to say that individually there aren’t better options available, but I think I would stick with a matching set.

Greetinx,
C.