Choosing Sub-woofers. Please advise ASAP.

" If you want to make bass, you can either move a large driver slow or a small driver fast. If all other factors are equal, there'a no difference. "

" That doesn't make any sense. A driver's movement corresponds to the frequency it's asked to reproduce. If it's a pure 32 Hz tone, the cone will move at 32 cycles per second, regardless of the cone's diameter. "

That's not true. The lower the frequency, the more air you need to move. If you make an 8in speaker move the same amount of air as a 10in speaker, then you get the same frequency. That means the 8in speaker has to move faster than the 10in speaker. 

Check the specs on some speakers. Quite often you'll see speakers with smaller drivers that can go just as low as speakers using larger drivers. A good starting point would be to have a look at Carvers Sunfire Sub. He does a way better job of explaining this than I do.

http://www.sunfire.com/whitepapers/Sunfire_Subwoofer_Whitepaper.pdf
"

mb1audio02

The lower the frequency, the more air you need to move.

Of course!

sautan904,

     " 2x 12" it is.  Yes. My stereo system will be setup and professional tune for my listening area with acoustic treatment too.
home theater will be setup by another HT and Mcintosh specialist."

     Well, you made your decision and you'll soon know the consequences.  .   Are you saying one team is going to setup and  tune your room for music (including room treatments) and then another team is going to come in and setup the same area for HT?   

   If so and unless these 2 teams are working as 1 team from the onset and have a plan that understands the compromises that are inherent to having 1  area sound good for both, you may be headed for disappointment at the results.  
Will the setup, professional tuning and room treatments be geared in favor of music or HT?

Will the setup be geared to sound good at only 1 listening position or will it be geared toward sounding good at all seating positions in the area? 

How will the  2 subwoofers be positioned in the room to avoid the inevitable peaks and nulls that result from having only 2 sources of low bass frequencies in a room?  

Sound waves behave much differently in a room at 200 hz and below than they behave at over 200 hz.

 Attempting to produce accurate and extended bass performance throughout a room with only 2 subs (no matter what size subs or room), room treatments (no matter how extensive) and DSP (digital signal processing) has proven to be not only expensive but likely futile.  

Attaining good and evenly dispersed performance in your room on frequencies above 200 hz is going to be a piece of cake compared to attaining the same on frequencies of 200 hz and below. 

The inconvenient truth is that attaining good and evenly dispersed bass performance on frequencies of  200 hz and below in your room with only 2 subs is not going to happen.  

I'm sure you're skeptical but that's healthy and I was skeptical, too.  The proof will be evident once your setup has been completed; just play some content with repetitive bass and listen to the bass in each of the seats in your listening area.
 If the bass performance varies by seat position (bass is more prominent at some seats and lacking or even nonexistent at others) that means you have bass frequency standing waves in your area that result in peaks (overemphasizing the bass), nulls (underemphasizing the bass) and possibly cancellations (no bass percieved).

Okay, now the good news; When you realize the bass response varies by seat position, this is solvable through setting up a distributed bass system in your area that will result in consistently good bass response at all positions in your area.  Unfortunately, this means you're going to need a minimum of 3 subs (will work with 10" or 12" subs) and possibly up to 4 subs setup in a precise distributed array method.

This is all just the result of physics and  wave propagation laws that cannot be avoided.  Bass wave propagation within a room have been studied extensively by acoustical engineers such as Dr. Gettis and Dr. O'Toole.  They have published numerous white papers on bass wave behavior and experiments in various room sizes with supporting empirical results that have been independently verified multiple times.

The gist of their experimental testing conclusion is that the most effective method for reducing bass peaks, nulls and cancellations and attaining good bass response in any room is the use of distributed array bass systems.  The found that the more source points for bass (subs) in a given room, the better the quality and dispersion of bass becomes in that room.

Obviously, there is a practical limit to the number of subs in any given room.  Fortunately and crucially, they discovered there was a threshold of 4 subs in a given room that resulted in reducing the vast majority of peaks, nulls and cancellations in a given room and beyond which additional subs only resulted in  marginal improvements.  This is why the better distributed array bass systems typically consist of 4 subs.  

Hopefully, your setup teams will be familiar with the distributed bass array system procedure.  If they need assistance, I detailed the procedure in my linked thread on my previous post on this thread.  You can ignore the parallel wiring section since my system uses 4 non-amplified subs while yours will use amplified subs.  They'll just need to follow the sub positioning procedure and run line level cables to each sub and connect  the power cord to an electric outlet. I'd suggest hiding the connecting cables for aesthetic reasons ( I drilled holes in my floor and ran all cabling in the crawl space below. 

My motivation in posting on your thread and others is solely in sharing my knowledge about the effectiveness of distributed bass array systems and how well  it works in virtually any room to such an impressive degree.

  I consistently notice many threads that imply that they believe they can achieve good bass in their room if they only use a certain brand or size sub but rarely consider the number of subs and their precise positioning.  I increasingly think this is the case because of the simple truth is that most people don't know about distributed bass array systems and how well they work while  having the additional benefit of not requiring any room treatments, room analysis, equalization, DSP or any other tools and software many people believe is a good solution for achieving excellent and well dispersed bass performance in any given room.

     Again, I'm not a dealer of anything and have no financial interests in distributed bass array systems.
     I'm just an audio enthusiast who stumbled upon a great bass system method who wants to share the wordwith my fellow audio enthusiast brothers and sisters,   
   Tim   

Tim, thanks for providing us all with some excellent inputs and food for thought.

On a different note altogether, I would ask the OP in all seriousness if he has considered the ability of the listening room floor, and its support structure, to handle the weight of all this stuff. By my calculations, including the not particularly heavy E-110 subs the equipment that has been listed weighs a total of about 1600 pounds. And given that the kitchen is adjacent, the listening area is apparently not in the basement.

Seems like a lot of stuff and a lot of weight to be putting in a 16 x 14 foot room, in addition to equipment stands and racks, source components, furniture, and people. And even more so if you were to go to larger subs and/or more subs.

Regards,
-- Al

It is a lot of stuff in a smaller room sound wise as well. Benefits of proper subs with good full range speakers and amps to drive them is more marginal but still real.   It's all a matter of how much of a total assault is really needed or desired.