well really one could say that 6 subs is better than 4 or hell 8 subs is better than four or six. one in each corner and one at each mid wall. heck really for this where do we stop. I only need so much volumn in the LF. where does it stop. looking at a price point and best LF if I were to buy 2 EP 500's at $2200 or four at $4400 or do I go to $10000 ?
I am pretty well sure that if I bought 4 EP500, I am not going to hear the difference with my ears in any room that is worthy of $6000 more
The biggest thing to get out of the article is that the biggest reason to get more subs is to have smaller seat to seat variation in frequency response from 80 Hz and down. It is relatively easy to set up one subwoofer so that one seat is great, as long as the sub is big enough for the room dimensions and we are talking about a rectangular sealed room. Just google search crawling for bass and you'll find several articles that go through the procedure. The difficulty comes when you would like to have that same good frequency response from 80Hz and down in each seat in a home theater setup with say 6 or 8 seats. The easiest way to do that is with either 2 or 4 subs AND seat to seat variation doesn't necessarily improve going with more than 4 subs. But the improvement in seat to seat variation with 4 subs is very similar to that of 2 well placed subs.
An added benefit of going with multiple subs is that you gain extra output in comparison to one sub, if they are placed well. Only people with enormous rooms would need to buy extra subs in order to get sufficient output at reasonable listening levels. After all, Axiom, Hsu, SVS, Rythmik all make subs that will be able to give good bass output in very large rooms.
