Subwoofers - crazy upgrade!

@audio_guy_uofw 

I am not aware of any literature on stacking subwoofers versus dispersing them but I agree with your understanding of the latter's advantage.  

The curve below shows how a four speaker distributed bass array (DBA) can not only extend frequency response, but perhaps more importantly, smooth it out. 

The two waterfall graphs below demonstrate the DBA's impact on room modes (standing waves). I believe the smoother frequency response and diminished "ringing"  are more important than the extended frequency response.

Quite simply, it works.

@audio_guy_uofw  I agree with your point. Stacking subs like the REL concept is good if the implication is to allow sound to more focal and directional which this curtails an "array" sort of speak. Logically, this will only work if you have a big enough room but it is not going correct acoustic room issues. Only way to correct  is room nodes in a fixed environment is either physically moving the speaker or seating location and treat the room or electronically apply processing which is more complex to achieve without the tools and resources.  

BTW, I still have my REL sub and I might not let it go anytimr soon but the Velodyne SC-8 pair just has more body and inpact then the REL but the REL is more musical. I like both REL and Velodyne along with SVS and Rythmik but they all have different philosophy and agenda. You need to find with one works for you.

@tcutter Excellent data on the benefits of distributed subs. Google "Tod Welti subwoofers" for some interesting research and data on the impact of multi-sub arrays and subwoofer placement.

Sorry Todd Welti

@audio_guy_uofw 

Done, but thank you.