Single vs. Dual Subs

"Seems" and "is" are two very different things, for sure when it comes to subs. Duke makes his Swarm with plugs enabling you to convert one or more ported subs to sealed. After studying the matter and talking with Duke mine were made with two ported, two sealed. I also have a 5th sub that is ported iso-baric.  

The truth of the matter is there is no "integration" process with a DBA. You plop them down, you set the levels, they are "integrated" whatever that even means. To me it means the bass is seamless with the rest of the sound stage. This happens automatically. You could use five completely different subs or five all the same, no difference. So save your money. 

Properly integrating a sub is really hard work, and rarely done by 90% of those who buy a subwoofer.

Technically, correct! I would even go as high as 100%. But 90 will do. Which is why I always and only recommend a DBA with 4 subs. Try and do it with just one and you are doomed to failure. When even the guy who uses one knows it is really hard work, and even then works only rarely, everyone should listen. 

And then go out and get more subs. To do it right. 

1. mc ~ " It is all summed at that frequency anyway. But, whatever. "

2. Kindly explain HOW, in your opinion, that happens???

Why am I required to explain HOW?

What if the HOW is automatic? What if it turns out the HOW cannot be anything BUT?

The wavelength at 80Hz is 4.3m or about 15 feet. At 20Hz it is over 17m or about 55ft. https://www.translatorscafe.com/unit-converter/en-US/calculator/sound-frequency-wavelength/ HOW are you going to ever manage to record that in "stereo" with any sort of ability to localize the sound without using microphones placed at least that far apart?? And in a room many multiples of those dimensions?

HOW are you going to do that?

Even if you do, HOW are you going to manage to play it back in stereo, in a room with dimensions smaller than the wavelengths involved?

HOW?

It is all summed at that frequency anyway. But, whatever.

Indeed, the multiple sub solution outlined by Toole and on which the Distributed Bass Array approach is based is a game-changer. Multiple subs distributed asymmetrically around the room effectively minimizes the problem of bass modes. Then when the subs and everything else are isolated on Townshend Podiums and Pods this virtually eliminates another major source of room mode excitation. The combination of the two is stunning. It takes a huge amount of bass traps and other room treatments to match what isolation and DBA can achieve.  

Then if on top of all that you go to Townshend F1 cables, these eliminate yet another source of harmonic resonance. 

The old-school approach of EQ and room treatment really is old school. There are much better solutions available. People are catching on. Good to see.

xcool - Our ears aren't good at locating low frequencies so subwoofers don't contribute to the stereo image. In fact you will probably find that the best locations are not near your speakers or symmetrical.
What you're looking for is for each sub to excite different room modes so that they balance one another out to some degree. If you're not familiar it might be worth looking up 'room modes' and 'standing waves'. 

Excellent answer. My system is a great example. There are 5 subs asymmetrically placed around the room with each one a slightly different distance from a corner than the others. With music playing, even with plenty of bass, you can walk right up to any of them and think it is disconnected. In fact I wasted a lot of time in the beginning doing exactly that! 

HOWEVER in spite of this when listening to music it is incredible how the bass always has some sort of definite location or character. What makes it so incredible is this happens even with bass notes that seem to have no sharp transient or leading edge. Like a big drum whack, it makes sense your ears are cued to a location by the initial whack on the skin of the drum. Or pluck string bass, same thing, the initial string plucking off the fingertip. But all kinds of bass does this too. It SEEMS to be localized BUT it is NOT and the proof is I can run the amps mono and STILL hear the exact same localized bass!

None of this makes any sense other than our hearing does not localize very low frequency bass but does localize higher bass AND THEN combines the one with the other to form a clear image of where the whole thing is coming from.

In other words, a great example of psycho-acoustics.

Strictly interested in confining the discussion to your pre-determined conclusion. Wonderful. But you get the answer you weren't looking for anyway. Each additional sub, by being in a different location adds to the number and location of bass modes. The result is that for each additional sub the bass becomes smoother, and smoother bass is faster cleaner more articulate bass. It also improves extension, slam, and dynamic headroom. The man who wrote the paper discovering the distributed bass array approach you are so intent on not talking about even reduced it to a mathematical formula expressing the improvement of each addition sub.

The single greatest development in high end audio in a generation, but you don't want to talk about it. What a shame. Oh well too late now.

Your single sub by the way never can be "dialed in perfectly" but in order to understand why you will have to first permit talking about that to which your mind is currently closed to considering.

Wouldn't it be wonderful if we could just dictate to the world how things are? Maybe. But it would not be the world we live in now, would it?