I got religion with a modest home theatre system that was in my front parlor-- nothing especially WOW, an older Meridian pre-pro that was a cast-off from the bigger projection system, a McI multichannel amp and a small array of Mirage speakers. Like I said, nothing special, perhaps a little better than a ’box store’ system.
I finally discarded the Meridian b/c it was long past its sell-by date, and bought a mid-range Marantz AV pre-pro. It came with a very basic form of Audyssey. The degree to which that tightened up a fairly small powered woofer in this modest HT system was surprising, at least to me. Most evident playing the music from a soundtrack on a Blu-Ray disc.
I now use a very modest DSP (DSpeaker 8033II or whatever the latest model is) to control a pair of 15" sealed subs in my main two channel audio system.
They are powered from a separate line out on my line stage so the main speaker system, with its integrated woofers, runs full range and the DSP unit is not in their signal path; it only affects the subwoofers, which are, after the test signals were run, set to roll off at 55hz on a steep (-24db/octave) slope. It’s a fairly big room, and I’ve managed to get these subs to cohere nicely with the main speakers, which are Avant-garde Duos, a hybrid horn-dynamic woofer design.
I’ve very sensitive to discontinuity-- having lived with electrostats for decades and never satisfactorily blended dynamic woofers with those, this works. Not a huge investment in wooferdom, or in the DSP unit. I gather than these units work by lopping off peaks, not adjusting for dips in frequency response.
The result is not an audible deadening of the music- perhaps because I’m rolling off pretty low and keeping the DSP unit out of the main channel signal path.
Certainly cheap enough to experiment with----