@mahgister --
We can live happy at 50 hertz....
I am....
What has surprised me is how much a hard deck of 50-ish Hz actually suffices. For music you get a long way with this, and it's certainly much more important how >50Hz is reproduced than more blindly going after added extension. Indeed, hunting for an octave lower can be an expensive endeavor, in more than sense, not least of which is potentially making matters worse for how the bass above it and in very general is presented - if not properly implemented.
But the question presses itself: should not lower than 50Hz suffice? It's a matter of how you go about it, what your goal is and the time and effort one is willing to invest. To me it's been about weighing the potential disadvantages against what could be gained going with lower extension, something's that is also tied with the specific bass principles I've pursued and their limited bandwidths, how it may affect sensitivity, structural integrity and specifics with floor construction, the impact on enclosure size (i.e.: and inevitability with horns), and so on. A close to 25Hz tune seemed a proper balance to me all things considered.
Properly implemented an honest octave lower than 50Hz makes a difference with lots of music and not least films, I can tell you that.