I found this
article very interesting and a confirmation of many things that I have believed are necessary for accurate playback.
Since it's a very lengthy article, I decided to open a thread for those who may have interest in the subject, as well as anything to contribute. The excerpts are small clips of the sections that talk about the differences between conventional subwoofers and the roraty blade technology.
This describes very well the points I have tried to make about resonant alignments. I'm not a physicist, so I just state the simple facts and leave to whomever disagrees or is interested to find the specific science behind it, either way.
Of course, the article lumps all current alignments into one opposing technology in it's descriptions of the differences with the TRW, but actually, the different alignments can certainly be separated into sub categories of differing degrees.
Here, they discuss the results of a test that used the M&C canon blasts, where they had set up the TRW as well as 'the biggest, baddest, most expensive' conventional subwoofer in the world (I don't know what that is, but I am led to believe that it is a ported sub. Note the bold section for later comments, made bold by me.):"In effect, the conventional subwoofer takes in all the incoming energy below its resonance frequency (which it can't reproduce at the correct frequency), and converts this lower frequency energy into ringing energy at the higher frequency of its system resonance. And, because the lower frequency, near DC, energy from the cannon shot just keeps on coming temporally, the conventional subwoofer can do nothing but keep on ringing temporally, frantically flapping in a totally spurious way, and madly pumping as hard as it can, trying to dissipate all this incoming energy, and thereby creating the maximum amount of spurious garbage that it can, for a sustained period of time.
The conventional subwoofers are alternately pushing air into the room and sucking air out of the room, over and over, for a long period of time, whereas the true input signal from the cannon shot should be continually pushing, into the room air and into your body and ears, for this entire time. No wonder the conventional subwoofers sounded so obnoxious, and so phony, on these cannon shots!"
Here is the crux (made bold print by me):"A.1. i. Spurious Garbage from Conventional Subwoofers
And we've saved the worst sonic offense for last. Just after their initial powder puff impact on the cannon shot, the conventional subwoofers went into sustained wild oscillating ringing, frantically flapping and pumping back and forth, in totally spurious misbehavior that was not at all representative of anything in the input signal, of anything in the actual sound of the cannon shot. This totally spurious mad pumping misbehavior sounded just like what it was, spurious garbage totally unrelated to the true sound of a cannon shot (it sounded even worse than a boomy bass overhang, which at least is related to the original bass sound).
What's going wrong here, so dreadfully wrong? As discussed above, conventional subwoofers spuriously ring, in their own cycling pattern unrelated to the input signal commands, in region 3 of their time domain response to a transient, and this ringing is especially bad, in both amplitude and sustained temporal duration, with vented bass subwoofers."
I agree with the article in general, as it's well thought out and each point has been tested before discussed, but I wanted to bring up this point regarding these clips:
I don't see the IB or any other sealed alignment as being limited to 16Hz (which they mention earlier tin the article) and I don't see it as sucking air in and out of the room (as the ported sub does) as they describe 'conventional subwoofers'.
There's no doubt that the TRW has advantages over a sealed alignment, but I believe that they leave an out for multiple driver sealed subwoofers in many of their arguments, regarding it's being equated to all other 'conventional subwoofers'.
I just thought the article should be linked and many of it's points could be great jumping off points for discussion.