Getting bass right means you need to have the bass emanate (in most rooms) from several locations at once. This is because most rooms have standing waves forming at bass frequencies, and no amount of power to correct a resulting deficiency at a certain frequency at the listening chair can fix it- the more power you put in the standing wave, it just cancels using the same power.
This is why room correction and bass traps work poorly at best. But if you have multiple bass sources (IOW a Distributed Bass Array) then the standing wave can be broken up, resulting in evenly distributed bass throughout the entire room. It is obvious this is the more elegant approach.
So its really not all that advantageous to have a speaker that plumbs the the bottom octaves if that output isn't heard and felt at the listening chair! If the bass modules don't go above 80Hz they won't attract attention to themselves as generally speaking, bass is omnidirectional to the human ear below about 80Hz. So in most rooms if you want to do it right, a speaker that goes down to just below 80Hz can do the job nicely if supported by 4 asymmetrically placed subs (two being in the front).
If you have one sub, or just two, it will be seen that their ideal location probably isn't the same as where the main speakers have to be (as mentioned earlier). But if you have main speakers that do make it into the deep bass regions, you might only need 2 extra subs placed along the sides or in back to break up the standing waves. That is how I'm doing it at my house, since my main speakers go to 20Hz. If I had it to do over though, I'd get a set of Swarms from Audiokinesis and just have a much smaller set of main speakers in front. But I like my Classic Audio Loudspeakers- they are some of the best speakers made.
This is why room correction and bass traps work poorly at best. But if you have multiple bass sources (IOW a Distributed Bass Array) then the standing wave can be broken up, resulting in evenly distributed bass throughout the entire room. It is obvious this is the more elegant approach.
So its really not all that advantageous to have a speaker that plumbs the the bottom octaves if that output isn't heard and felt at the listening chair! If the bass modules don't go above 80Hz they won't attract attention to themselves as generally speaking, bass is omnidirectional to the human ear below about 80Hz. So in most rooms if you want to do it right, a speaker that goes down to just below 80Hz can do the job nicely if supported by 4 asymmetrically placed subs (two being in the front).
If you have one sub, or just two, it will be seen that their ideal location probably isn't the same as where the main speakers have to be (as mentioned earlier). But if you have main speakers that do make it into the deep bass regions, you might only need 2 extra subs placed along the sides or in back to break up the standing waves. That is how I'm doing it at my house, since my main speakers go to 20Hz. If I had it to do over though, I'd get a set of Swarms from Audiokinesis and just have a much smaller set of main speakers in front. But I like my Classic Audio Loudspeakers- they are some of the best speakers made.