How do small woofers produce large bass?

@deep_333 

better idea to lose bass extension below 80hz, get the sensitivity up to 100db

That's home theater speaker design like JTR. There is also a market preference for HI-FI speakers. Also if you speak into your phone and look at a spectrum analyzer app, you'll see your voice at 50Hz or below, which you can localize. 80Hz crossover is not good in a HT setup using a single sub in LFE because if the sub in back, dialog will come from there instead of the center speaker. That's the compromise with HT speakers if you want SPL. There's less of a compromise with capable full range speakers. They're capable of +105dB peak. Most people don't listen at an average above 80dB. Simply calibrating is painfully loud.

if you can actually put your main speakers now in the right spot for a low bass/distributed bass Geddes array...problem is those spots will be lousy spots for everything else a speaker has to do, imaging, soundstage and so on

That theory was also disproved with the measurement I posted. Also the speakers are toed 2' wide of MLP (middle of two outer seats), not at MLP as many theory suggest. 1' wide is the best imaging and soundstage for MLP, but not for the other seats. Another thing; the flat response is mainly a point of reference. Many prefer a v-curve for music.

@deep_333 wrote:

I run my pro pioneers (dual 12s) with a dual 18 horn loaded pro sub...or i swap it with a 21 inch  sub. There is something about these large subs covering the low octaves, i probably won't be going under 18 inch subs hereafter.

Is the 21" variant also horn-loaded? I also crave those larger woofers of higher efficiency, but the important aspect to me is the specific design in which they're implemented; for sub duties I prefer those larger drivers to be at least partially "hidden" and not direct radiating, as the latter seems to more readily expose the sense of a large woofer cone, not as much for giving the feeling of an effort being made as for having a "cone sound."

When used in horn-loaded or high order bandpass designs however where the woofer is more or less hidden the end result is a typically cleaner, less character-laden and more "the bass is simply there"-feeling with the variable being overall wallop/SPL and extension depending on the driver diameter, design direction and size. 

The crap coming out of things at axpona and the like..these boys have some things to learn.

Absolutely. They're usually bound by small size and still wanting to have their cake and eat it too (i.e.: extension from small size, with all that implies).  

The Tekton guy perhaps managed to word some of this...

https://youtu.be/4PIE1znQv2U?si=uNAviV8EcHfLp502

Indeed he does. Thanks for supplying the link. 

There are other designs and enclosures he does around that 21 inch driver. Here's an example. I guess you could tell him what you want. 

I assume  you've seen the regular one, which is the one i currently have.

@phusis wrote

Is the 21" variant also horn-loaded? I also crave those larger woofers of higher efficiency, but the important aspect to me is the specific design in which they're implemented; for sub duties I prefer those larger drivers to be at least partially "hidden" and not direct radiating, as the latter seems to more readily expose the sense of a large woofer cone, not as much for giving the feeling of an effort being made as for having a "cone sound."

@deep_333 wrote:

There are other designs and enclosures he does around that 21 inch driver. Here’s an example. I guess you could tell him what you want. 

Oh, I know Mr. Ricci’s Othorns and the driver the design is built around, the B&C 21SW152. Great subs, arguably some of the best around within their frequency range. They are the ones I originally wanted a pair of in my speaker setup, but eventually opted for another tapped horn option with a smaller, 15" B&C woofer. 

I assume you’ve seen the regular one, which is the one i currently have.

Classic ported design. What’s the tune of this?

Single small woofers will have issues, but a few small woofers can be magical. Martin Logan made small sub arrays with 6in and 8in woofers. They hit hard, and deep! 

It's mostly about surface area. 3 8in woofers have more surface area then a 15in one. Of course the smaller woofers can move faster, be more ridged, have more control at high excersion. 

Generally for bass you need surface area, proper cabinet, long throw, and power.