Bass Response and concrete floors


I was talking to a Dynaudio dealer the other day and asking about the Confidence 5's in comparison to the rest of the Dynaudio line. The 5's are apparently being cancelled with two new models being released in the Confidence line, based on the Evidence technology.

Anyway, he asked what type of flooring the speakers would be on. I said concrete with thick pile carpeting. He said the bass response on a concrete floor, even with carpeting, would be muted, that the Confidence 5's need a floor with give to produce decent bass. He said that the bass would roll off around 50 Hz on a concrete floor.

I've seen so many very positive comments about the 5's, but I suppose that people who are satisfied may well be using them on a main floor built on joists. The dealer indicated that I'd be a lot happier with the 3's on my floor.

Anybody know why this would be? More importantly, is this a common behavior of floor standers on concrete floors? Is it a general "rule" that if you have concrete floors, you'll get better performance from a high quality monitor? Thanks for any info -Kirk

kthomas
Many speakers couple to the floor and resonate through the floor. Concreate floors don't resonate (or not at a useful frequency). You could consider a pergo floor over your concrete. I did this in my audio room and it worked remarkably well. I put in an oriental (wool) area rug for some sound absorption, but carpet on the concrete (which is what was originally there) sounded very muted.
This sounds very odd! It seems to me like flex in the floor would hinder the pressurization of the air in the room to get proper bass. Have you ever tried to get real bass in a room with a drop celing? It can't be done IMO. I have always had great sound on concrete floors, this is new to me. If the speakers were designed on a floor using wood joists I suppose they voiced the speaker for that? Any other ideas? Sounds like a perverted tone controll to me. Loudness contour anyone?
I have a concrete floor in my listening room and must admit that my bass was not that super until I added subwoofers and now there is no question about bass. I think the downside of wooden floors is that you then have to worry about boomy midbass. I would believe the salesman, though, if he says one model works better with concrete floors.