Physics of downward firing woofers

"....actual experiences...." *G* OK...

Agreeing with Erik @ 11:25, my modest bottom-firing sub is up against the wall.  If I opt to listen to my front-firing speakers, they pass up to a pair of 12" +/- 15" above the concrete floor. They in turn pass up to a 6' active with a 6" passive physically above the 12".  Both are aligned +/- 30" from the back wall to accommodate the dipole ribbon above them that takes it to top....

...when I'm not listening to omnis, anyway. *S*  Not your typical approach, but I like the results.  All the bass and lower mids one could want, unless you're into 'burping' in the car.  Not the sort to hang out here @ AG... ;)

A successful design with downward-firing woofers were the Snell Type A's. Excellent bass extension and impact! No need for a subwoofer! I own the Type AIII's and can attest to this - some of the best dynamic bass available! And the against-the-wall placement frees up a lot of space in the listening area!

Anyone have or compared the Sumiko subs? They seem well received in home audio circles. They use a downward firing active driver and a front firing passive, which is said to help make them integrate easier. Seems to make sense.

Maybe the only real listening-oriented problem I could say that I’ve ever really run across in downward-driver designs is that, as a rule, I find there can be a big difference really between "bass impact" (or "wallop") and "bass dynamics". It’s possible to have lots of impact and yet still have (sometimes) even dreadful bass dynamics. Yet many people might be inclined to say that that kind of sound is as good or even preferable to one that tics all the traditional boxes in bass reproduction (???). Although it’s usually not to quite that objectionable degree audibly, that to me may be about the worst thing you can find yourself getting into with downward designs, that and the slight loss of timing that seems to go with it. But, it’s possible these designs may work as good or better in some "problem rooms" where there may not be enough space to properly present a direct setup. But, that’s one reason why I say above that dynamics can be better with a direct setup. They are not necessarily any stronger, they are just presented more fully intact.

I know when trying to assess downward subs that there tend to be sooo many other variables involved (placement, room size, etc) that establishing the exact audible effect the downward arrangement actually has can end up getting pretty intractable.

mapman, now that (the Sumikos) sounds like the best of both options...although now it'll drift into 'the driven should be the direct, the passive the downer'.....;)
One could always void the warranty....*L*