How do you chose speakers based on room size?

Thanks, Duke for the erudite reply...I have a lot to learn/experience and appreciate the selflessness exhibited by you and others in our community.

Best for the New Year,
Sam

Gentlemen,
Timely topic. I've got an open plan listening area--my my living room--that is roughly 15' long and 11'3" wide with a "mostly" open wall on the longer side (that is, from the back/listening end wall, the open wallspace extends about 11-12' toward the speaker end). 7'6" ceiling. I am using B&W CDM7se floorstanders.

If there is a problem presently it is with a weaker lower end. (Duke hit the nail perfectly.) Overall positioning has been tweaked to the point where I am happy with the sound but I cannot seem to get past the bass issue. On most recordings I really don't notice (but imagine that there is still an effect that will be appreciated if the issue is corrected) while on others the lack is clearly noticeable.

We've got carpet on the floor and upholstered loveseats at both the closed side and at the listening location. I'm guessing these don't help the bass but the rest of the frequency range sound so good I'm in a quandry.

The wife and I would like to put in hardwood and to replace the loveseats (the cats are slowly shredding them) with leather but I am really nervous about "hollowing out" what is now an otherwise very rich sound (absent some degree of bass).

My speakers of choice (the next upgrade) would be the larger B&W 803D which also have the benefit of better (and additional) drivers and B&W's diamond tweeter. (http://www.hometheatermag.com/floorloudspeakers/1005bw/#) I'd been concerned that the size was a problem but Duke has suggested otherwise. Any comments on current setup or proposed changes (gear or room) would be greatly appreciated.

I always said that the more the room acoustics become a challenge. You have to try a listening triangle in that room as a starting point and choose your speaker type.

This is a great thread !

I was wondering if we could take this a step further ?

Is there some aspect of speaker build/design that one should look for in those small room/nearfield situations that would be different than the larger rooms and visa- versa ? Something that would not be placement specific .

In the larger room one will want to turn up the volume so as to pressurize the room while sitting farther away from the speakers . But in a small room one will want to turn down the volume because there is less area to pressurize and you are sitting closer the speakers .

Newbee addressed speaker types , Duke talks about spreading the bass sources and reducing the port frequency in a tight space , mapman suggests tight driver integration for small rooms and bigger drivers for large rooms . But then J Bailey speaks of single drivers for easier driver integration and uses 3 way big woofer back loaded horn speakers in his small room .

Are there some simple guidlines for design as well as size ?

Thank you .

Saki, Speaker placement (including the rooms that they might work well in) is critical for just about every speaker design.

Some folks pursue set up diligently until they have optimized it, some more than others until their significant other or their own sense of asthetics takes over, some not at all and everything in between.

Your suggestion raises the toughest and most common (I think) situation facing the majority of audiophiles. Good sound in a small room. Tough under the best of circumstances and especially so if your expectations are demanding, but to exclude placement as a consideration presumes that there is a speaker with audiophile pretensions which will sound good no matter where you put it or where you sit when you listen to it.

I don't know of such a speaker, let alone provide 'simple guidelines' or advise, apart from getting a pair of sealed enclosure cone driver monitors that can be placed near a wall or on a book shelf, a sub woofer to fill out the bottom end, and an equalizer of some sort to balance out the very uneven sound that would be likely. Not very good advise IMHO unless you don't care about things like a balanced FR at the listening position as well as a full (wide/high/deep) sound-stage.

FWIW.