[opnly bafld]

That is what I said, but the reverse is not necessarily true.
Well, all except the two types part, but I have read the definitions that I gave from other sources.

[Bob in St. Louis]

Here are a few images I borrowed from the Net.
These are all IB. These are all "closed boxes". But this isn't what I would think Vance was refering to.

[*Scotty*]

Bob, those pictures resemble low frequency arrays with military applications.
Scotty

[Bob in St. Louis]

Bob, those pictures resemble low frequency arrays with military applications.
Scotty

Yea, close..... But they're in attics, crawl spaces, and basements. No weapons going on here.

There are a group a fellas on a forum dedicated to IB that would agree with you though.
The forums is: http://ibsubwoofers.proboards.com/index.cgi
Since their tag line is; "Hear The Bass, Not The Box"
I dare anybody to log on there and tell them they're all listening to sealed boxes. I Double Dawg dare ya. 

Bob

[Letitroll98]

No mention of Transmission Line?  (Other than an aside about Salk speakers)  IMHO a vented design that competes very favorably to similar sized sealed systems (which would be called acoustic suspension by us old fogies).

[Bob in St. Louis]

HHmm.... I was talking to a fellow today about TL's as a matter of fact.
But it didn't even connect with me regarding this thread.
Good catch.

Bob

[Æ]

No mention of Transmission Line?  (Other than an aside about Salk speakers)  IMHO a vented design that competes very favorably to similar sized sealed systems (which would be called acoustic suspension by us old fogies).

No mention of horns either. I just love the dynamics of a gigantic bass horn!

[Æ]

Here are a few images I borrowed from the Net.

I've seen those before. Pete Schumacher maybe?

[charmerci]

No mention of horns either. I just love the dynamics of a gigantic bass horn!

Ah! Memories of my brother's and my 4 Klipschorns and the 1812 Overture! 

[Bob in St. Louis]

I've seen those before. Pete Schumacher maybe?

Not sure honestly. That's the beauty about stealing pictures from the net, it's just so....faceless, nameless and cold.. 
But they look like pictures I've seen in the gallery on the "Infinitely Baffled" forum. That's all those guy do, is build large displacement structures with the sole purpose of taking the cones rear wave out of the picture.
I've got one with (4) 15" drivers in it.

Bob

[Æ]

Not sure honestly. That's the beauty about stealing pictures from the net, it's just so....faceless, nameless and cold.. 

Pete Schumacher, a DIYer, lives in Ballwin, Missery (Missouri), you should look him up.

[Bob in St. Louis]

Ballwin?  I work in Ballwin.
Cool! He needs to be at my house. How do I get ahold of him?

How cool would it be that I rob pictures off the net to prove my point and the dude is from a few miles from me?
That's awesome.

Bob

[Æ]

Ballwin?  I work in Ballwin.
Cool! He needs to be at my house. How do I get ahold of him?

How cool would it be that I rob pictures off the net to prove my point and the dude is from a few miles from me?
That's awesome.

Bob

I'm not certain that the pics/woofers are his. He hangs out over at the PartsExpress Tech Talk forum, over 14,000 posts.

[Martyn]

The pics are definitely from the gallery at the Cult of the Infinitely Baffled. I recognise them from when I built my IB sub a few years ago. The folk there (Thomas in particular) were very helpful. I ended up with a pair of 18" drivers pumping in a manifold below my floor. I cut a hole in the floor and disguised it with a 16" x 16" standard return-air register. My wife barely commented! The sound is terrific - all crunch and no boom. I use it just for movies and the occasional multi-channel SACD; my mains have an F3 of 27 Hz and are quite adequate for music without any help from the sub. Those guys with the military arrays must be cracking their neighbours' drywall!