Subwoofer speed is in the room, not the box

Excellent bass should be clear like air or water and evidence itself only by the scale and dynamic range of the music being played and seemingly come out of nowhere and ignores the physical size of the room.

I agree and the way I achieved this is using an active crossover with 70 Hz low pass and high pass filters (4th order 24 dB Linkwitz-Riley) and biamping with a SWARM set up using 4 woofers.

@audiokinesis is not wrong, but the SWARM solution, like adding EQ, and traps, is probably NOT what audiophiles expect when they first think of adding a sub.

Again I agree, but audiophiles are less about education and more about aimless tweaking. So when they add a sub they expect it to be plug and play and not something they have to educate themselves on.

The idea that large drivers have excess stored energy which they can’t get rid of fast enough is bunk. That, and that alone, is my point. Which set of challenges audiophiles decide are best for them is for another thread.

I think the Danny Ritchie video linked earlier by @deep_333 proves this point, although I have had good success with 8" and 10" drivers and have no desire to go larger than that.

John Hunter of REL just has a different philosophy about how to use subwoofers. Not saying it's wrong, just different. As @tomic601 alluded to earlier I come from a different school of thought, one taught to me by Roger Modjeski (designer of the electronic crossover for the Beveridge 2SW) who finally convinced me to use subs (8" woofer in a 1/3 cubic foot sealed box x 4) with my QUAD ESL speakers. His recommended LP and HP cutoff was 100 Hz. Why? Simple, the speaker was designed with a 90 Hz bump and that crossover point eliminates the bump. Now the QUAD ESL will never make anyone's best bass from a speaker list, but without that bump the speaker would have significantly less bass output, so there is that to consider as well. On my box speakers which are Spendor 1/2e I use 70 - 80 Hz.

So the question is...If the high pass method makes the speaker sound so much better, wouldn't every speaker manufacturer use this superior method? Are all these displays competing for high end sound missing the secret sauce that would make their speakers sound even better?  Are they ALL silly?

If anything is silly its this statement. The better solution isn't always the one that the majority of manufacturers would choose to market or the one that consumers would choose to employ. It's been proven many times over with products across multiple industries. From a business perspective it's almost always about following the money.

I find it a bit strange no one to this point has brought up the amplifier in this conversation. If the amplifier could talk and express an opinion on filters, slopes, and frequencies, not to mention phase and damping we might be a bit surprised. After all its the amp that is coupled to the speaker.

Lastly, one of the reasons I actively bi-amp using separate amplification for the mains and the passive woofers is I still don't feel an amp, let alone a plate amp belongs in a box with the low frequency driver(s). I'm sure over the last several years the technology has improved but I still remain a bit stubborn here, as I once was about using subs altogether. Maybe I just need a bit more time.

ESLs will go extremely loud if they do not have to make low bass and they don't have to force an amp to drive a 30 ohm load.

@mijostyn that is kind of my point for crossing over as high as possible, but Roger always told me the amp has a say in this so for the mains speakers if we can keep the amp from seeing difficult loads it will be happier and run more efficiently with less distortion. Case in point is a Music Reference RM-10 on a set of QUAD ESL speakers. While on it's own it does a fine job, in a active bi-amp arrangement with a 100 Hz LP and HP it relieves it of having to drive the high impedance in the bass. For the bass speakers Roger just advised me to get a decent solid state amp with good damping.