You can add just about any sub. The more subs, the less the need for room EQ. I have five subs, of three different types, and its the highest quality most beautifully integrated bass I ever heard anywhere. Do a search for Distributed Bass Array, read up and understand why the most important question is not which sub but how many. https://systems.audiogon.com/systems/8367One Talon Roc sub.Two 10" sealed subs.Two 10" ported subs.No need to match or pair or anything.
