Physics of downward firing woofers

Downfiring is probably not a very good idea if you have carpeted floor. Unless I am terribly wrong.

I've never seen it make a difference. The Classic Audio Loudspeakers models T-1 and T-3 have down firing woofers. Somehow the bass sorts out how to get to your ears whether there is a carpet or not.

I think there is something to the height of the speaker off the floor, but my Fulton Premieres had down firing woofers and it was a lot closer to the floor than my CARs are. Overall the Fulton was less efficient, but I don't think that had anything to do with the woofers in particular.

inna 

I just make a joke. I learned long ago at a motivational seminar that "there are no dumb questions" 

Not sure what motivations they were using. The only thing that motivates me know is a good night sleep. 

Ralph, did you remove the carpet to compare or move everything to identical room ?

Now, why do I get tired of hearing about Classic Audio speakers? Seemingly no reason, right?

The main advantage of a downward firing sub is to avoid forward driver modulation that would compete for your attention by adding confusion to the highly perceptive mid and hi frequencies.
try reversing your subs and experiment with 180 switches and this is for many folks an improvement in focus.
Downward subs, when used with neutral speakers, will be complementary
 in balance.