I've set-up an old pair of wide-baffle 3-way book-shelf speakers in our 12' x 16' room as a nice listening nook for when our son, and his friends, take over our main lounge where the main system is set-up. I've set-up some tuned bass traps in the front corners and super-chunks in one rear corner, and after a bit of tweaking locations as well as use of DSP, have got good bass performance. The real remaining issue is a 8 dB dip centered at 40Hz (35-50Hz, Q~2). This dip correlates exactly to the cancellation from the back wall reflection. It probably not practical to address via room treatment and, with the main system involving multiple subs, I'm keen to keep this system system. Is it correct to guess that there is little benefit in solving the issue for most 2-channel music? But if I do attempt to solve it has to be with subs as room treatment won't address . Is this right?