seadogs1 ,
Thanks for the comments!
The T-Line vents out the bottom sides of the lower enclosure. If you look closely you will see three triangular openings. One is on the bottom front and the other two are positioned 90 degrees to it on either sidewall, nearest the front half of the enclosure.
I'll try not to give away the farm here, but the reason our T-Line does what it does is because it is designed pretty much opposite of most. The other guys have it all wrong - IMHO
Our T-Line works in a similar fashion to how our waveguides do with respect to the tweeter. The acoustic wave constantly expands until it reaches the vent, which after exiting, it continues to do so into the room. That's how sound waves naturally behave as they travel through air.
It seems unnatural to force them to do otherwise. So don't ask me why some design their T-Lines to taper such that the smallest cross-sectional area is at the vent. From a modelling standpoint, they look like little more than boxes that gradually turn into really long reflex ports. Oh, don't get me wrong, I understand exactly how they're "supposed" to work. "Supposed" is the key word here though. Although they extend bandwidth to lower frequencies just like a reflex design does, they usually generate a lot of frequency response "ripple" in the higher end of the pass band. Adding to that, they're low frequency efficiency is very similar to a reflex design in that they don't recover any more "wasted" energy than the reflex design does.
That's where our T-Line is different. Its efficiency is greater at the lower end of the spectrum, therefore it recovers a lot of the energy that would otherwise end up as waste heat in a reflex (or inferior T-Line) design.
Hope the above is of some value.
-Bob
