One woofer or a pair?

Theoretically speaking the human ear can only distinguish a stereo sound from mid to high freequencies.
What's the benefit of placin a pair of woofers for a pair of speakers?
Cleaner bass. In stereo, each speaker will have its own bass "tune". One subwoofer means your bass is in mono, and has to work harder to play both tracks.

That said, your budget matters also. For example; one $1500 sub is generally better than two $750 subs. Better to get the $1500 sub and then save up and buy the second one later. (Or whatever your $$$ budget is).

JJ covered this over at AA, so i'll try to summarize what the thread entailed. Even though the output of a sub is centered well below 100 Hz, most of what we are able to localize is the actual distortion coming out of the driver. Since the harmonics are above the primary frequency of operation, you can still form a sense of localization. As such, going to stereo subs tends to stabilize the image and even out the presentation across the soundstage instead of having the sound lumped or confined to one specific area.

A point that i brought up in that discussion is that downloading seems to mask the ability to localize a subwoofer. JJ's rebuttal was that a downloaded driver will have self cancellation of the higher frequency harmonics due to reflections in the pressure zone of the driver. Further reduction of harmonics is also heightened by the ( typical ) placement of the subwoofer on carpet and padding.

Speaking from experience though, downloaded subs work best only for extreme low frequency operation ( like what SUBwoofers were originally intended for ). They lack any type of punch or definition for upper bass notes due to the lack of direct radiation. This is also the main reason that you don't hear the distortion out of them, as it is directed away from your ears.

Downloading is also VERY tough on a driver, especially those designed with a lot of mass ( this lowers resonant frequency ). The weight of the cone tends to pull the voice coil out of the gap and sag the suspension. As such, excursion is minimized or at least drastically reduced. For that matter, so is power handling. A woofer that could normally take a "gazillion" watt pounding may now only handle a few hundred watts. AS such, a driver used in a downloaded sub needs a REALLY stiff suspension in order to operate best while maintaining good linearity and power handling. I found this out the hard way AFTER building a few downloaded models and then "throttling" them to death. Sean
Another freckin frequency fact question?

Marakanetz, how's the poetry coming?

I can think of two simple reasons: 1) you can use them as matching end tables and 2) you like your system to sound like your kid's car stereo. Just joking bass fans.

I admit my taste (or lack of taste) in music does not call for a sub and most of them I listen too are dreadful overkill. This, of course, does not include the folks at Agon who know how to integrate bass into a system.

I would like to ask a follow up question to yours. I read some time ago that two subs should be used used because under certain recording conditions (mic placement and what not)you will have bass recorded out of phase and when it is combined to one sub (channel) it will cancel out and you will have less bass than if you had no sub at all! Not being a sub fan I didn't give it much thought and now I cannot recall the source but if a fellow Agon could enlighten me it would be much appreciated.

Sincerely, I remain bassless and
Clueless, i would think that it wouldn't matter if the out of phase signal was presented by one driver summed to mono or by two in stereo, it would still end up cancelling itself out ( to a large extent ).

By the way, you REALLY do need to change your nickname. As your posts have proven, you are anything BUT.... : ) Sean
Using a single sub is more likely to excite specific room nodes. Using two subs spread out will allow more even response in the room since you are able to tune the positioning. Try moving a mono sub a few feet in either direction and listen to the difference, unless you have a room with extremely well distributed nodes, you should hear a pretty sizeable difference.

The Sound Broker
Can I be clueless, Clueless? I believe I can be... and I also can be curious too especially if I hadn't tried any of the woofer-speaker combos. In fact you might be right about no-sub effect and I would also wait for that answer that you expect. What about the vinyl records that are stereo but designed for the mono pickup as well?? ...

I also believe that giving a sub his freequency range you can improve your speaker's midrange(again depending on a sub quality). Now that's not a kid-stereo stuff.

Off the topic(poetry)
I've placed a few more psych poems onto my thread a long time ago. There were a few abstract dreams but I didn't capture them to write them down -- hard to be in control while you sleep. Besides I don't smoke &%$^ anymore and a probability of the quality abstract dream is much lower.
Before I smoked constantly and saw the dreams that I couldn't understand, but after a while I've realized that I can get up and be under my control to remember what was going on... The 2 worlds that I was trying to live before cannot be successfully combined: one of them will have a success and the other will have a failure...

...evry house has windows up
from every door you can walk a step
but if your way is imprinted with chalk
where would you go if the snow will fall?
In my experience, the only way to get away with a mono sub is if the crossover point is exceedingly low, meaning less than 40Hz. Anything above that and you will be able to localize it. I also agree about the virtues of downloading; it seems to couple to the room better, but again will only work well with very low crossover points.
I agree with Kevin. During the x-mas season my REVEL Sub15 had to go from the right side to the left of the room (because its space was needed for the tree :-) ). Just this move changed my systems sound in a frightening way and I was happy when the season was over - at least in this respect.
It seems to me that it is a matter of your room how you think and act about subs in general.
Good luck!
From all above posts I think that if you're using a pair of woofers you can use them as a "sub-speaker" and give it to work with higher freequencies than 50Hz maybe even upto 200Hz.