You can't get worthwhile deep bass out of a small enclosure period. JBL was wise not to try.
I absolutely agree with that. JBL have correctly gone for bass quality over extension.
However the fact remains that for movies people want the visceral impact it seems. For most musical sources, unless you are a pipe organ enthusiast, which I am, the last half octave is discretionary.
It is true that many main speakers, can go as deep as those subs. However that still leaves out the LFE output, unless you have active speakers and can mix it in.
The fact remains that by and large subs are big ugly cuboid boxes and not conducive to domestic harmony, so of course there is sales resistance, especially for multiple large awkward boxes, which look dreadful in most rooms. I have been on notice for some time to get rid of my two sub boxes in our family room. I have a plan and hope to take care of it shortly.
Even in my theater there is absolutely no room to place any decent commercial subs. Fortunately my main speakers, can easily rattle your internal organs and the furniture, with little power and without the use of sub drivers.
I have been thinking about all this of late.
Several things are clear to me about reproducing the last octave or two.
I am absolutely certain the TLs properly designed produce a far better quality bass, than any other type of design, at the same time requiring far less power to shake the rafters.
TL subs do not have to be boxy. They are large, but can easily be designed with a slim profile. This is important, as even in my large theater, there would be no room to place ANY sub currently on the market that reproduces the last octave without ruining the space architecturally and creating a dangerous hazard.
However it would be possible to design very slim TL subs, that would fit along a wall, or even behind a couch. To really achieve the best architectural results, then ultra slim drivers would need to be produced with novel motor systems. I have been doodling with this.
I continue to be enthused about my in wall sub in our large great room. That uses a 10" driver, but fills that large space. Not only that, but although the driver is the same sensitivity as the others, over the band it operates, it has to have power reduced significantly compared to the other speakers, so as not to over power them.
All this has convinced me that sub design needs a totally new approach. These subs with 1000 watt amps and more are just not the way to go. Brute force in any engineering design, is usually the wrong approach, and elegance will best it every time. The last thing any of the currently available subs are is elegant, in any design parameter. We must do better.
By the way, regular streamed broadcast form "Baby", the huge Wanamaker organ in the Macy's store in Philadelphia. They have been given by the long time Grand Court Organist, Peter Richard Conte. This instrument has just turned 110 years, since being moved from California in 13 rail cars 110 years ago, by John Wanamaker. The organ has increased two and half times over the years, and now is 7 stories high and has over 28,000 pipes and six key boards, and a percussion section.
I should start a thread on "Baby".
At least in this room, this instrument vibrates your chair and internal organs even when playing the quite passages, when the large bass stops are pulled.
The videos that are dark, will play if you click on "play on YouTube".