I just hooked up an Essex sub this afternoon for use with my Harbeth M30's. I haven't figured out how to get it integrated with the M30's yet, but I'm having fun trying. It clearly will add something. As Uomaragno says, however, it will clearly take some listening and tweaking. I agree with Uomaragno that it will add positive things to the bottom part of the soundstage, based upon what I am hearing. (I, too, listen to a lot of classical music.)