I use the MJA 50 subwoofer with my KN7000 and would not consider using the keyboard without the added depth of sound the subwoofer gives. Compared to other keyboards especially Yamaha, the Technics instruments lack sheer power and presence because of the timid and thin bass and drums. This has always been one of the big dissapointments with the KN7000 for me, but the addition of a sub woofer makes a big difference, and worth every penny.

Kind regards to all

Peter