Hi efficient speaker, bass problems

Unsound, I don't think the ear can hear all of these lags in the bass region.

That's one of the reasons bass is perceived as omnidirectional inside a room: Our time-domain resolution is so poor down there that the ear/brain system cannot tell the difference between the first-arrival sound and the reflections.

In contrast (so I've been told by a psychoacoustics researcher; never tried this myself), outdoors the ear is able to discern the direction of low frequency energy down to a much lower frequency than in a room. This is because there are no reflections to confuse the ear-brain system by arriving before it has resolved the initial impulse. We can hear direction at very low frequencies, as long as it's not masked by reflections arriving before our ear/brain system can isolate the first-arrival sound. All of those lags you mention arrive before the ear/brain can isolate the first arrival sound, so perceptually they just get blended in with it. And the room's effects on the frequency response are what dominates the perceptual modification of what would otherwise have been a clean first-arrival impulse.

I used to believe that the superior time-domain performance of a good sealed system was the reason for its "tight, natural" sound, but after reading Earl Geddes and Floyd Toole on the subject, I now believe that the in-room frequency response is the dominant factor by far.

Come to think of it, for many years the most natural-sounding bass I'd ever heard was from an IMF transmission line. A transmission line would inherently have poor time-domain behavior but might well have not only a room-gain-complementary native frequency response, but also significant physical displacement of its two bass sources (woofer and line terminus), with ensuing dissimilar room-mode-interaction from the two along with its smoothing effect. This would have addressed the two main problems of in-room bass reproduction: Gain from boundary reinforcement, and peaks-and-dips imposed by room modes (actually just different manifestations of the same problem). But no one really thought in those terms back then.

Duke

Duke, we have all read that bass is omni-directional, and yet very often it's very easy hear where the sub-woofer is (perhaps it's because the overtones appear to come elsewhere?). Despite the theories, some of us clearly prefer the sound of sealed boxes over ported ones. As the old cliche' goes; "the proof of the pudding is in the eating".

Stereophile recently claimed they had tested 750 speakers and the average sensitivity was 86dB . John Atkinson didn't come right out and say it, but seemed to prefer sealed box designs .
The only sub Iv'e heard that didn't give away it's position was a very large REL .
All this ( proof is the pudding ) talk is making me hungry .

Duke,

Bass localization is detectable indoors, get the math wrong and you will know, phase is absolutely critical.

regards,

Duke, "Come to think of it, for many years the most natural-sounding bass I'd ever heard was from an IMF transmission line."

So many folks who have been fortunate enough to be around Bud Fried's various designs echo the same thing. The corollary is that so few say it about most other true TL designs. Bud was intelligent/courageous/confident enough in himself to do things differently than everyone else without giving it a second thought; TL implementation being a prime example.

The last true example of the speaker Duke referenced was the Fried Studio V. So often, I say to myself exactly what Duke said. Though I've been around countless loudspeakers that produce much better bass on paper, to me, no speaker (OK, maybe his own personal O subwoofers, which I happen to have in my home) has ever made bass that was more perfect (actually, it's not even close) in terms of sounding like actual music. I admit that it's something that haunts one forever. Here's hoping one day I find a pair...