Best multi-purpose subwoofer

seasdiamond:
" Wouldn’t it be easier to just get 2 subs and run room correction than go 4 subs?"
    Yes, many users might be satisfied with 2 subs room corrected to provide good bass response at a single sweet spot in their room and it would be certainly easier.  
     I've helped several friends and family members with their smaller music and ht systems, usually just an a/v receiver, 3-5 spkrs and 1-2 subs. 
     They usually want good sound for 1-2 people from a sofa facing an hdtv.  I've positioned the mic at the center of the sofa and this has resulted in decent bass response for anyone sitting on the sofa but poor bass response at other seating positions in the room.
     Makes sense, right?  Room correction is only capable of optimizing bass response from the single spot in the room you are giving it frequency response and volume data from (wherever you decide to position the mic). 
     I haven't been overly impressed with the results of the limited room correction systems I've utilized.  I've found I can easily attain better bass response results by positioning the subs by ear and trial and error, though I am able to get the best results using 2 subs rather than just 1.
     In my system, I was looking to get very good bass response for music and ht at all 7 seating positions spread around the perimeter of my 23 x 16 foot room.  I positioned all 4 subs sequentially by ear and concealed all the wiring by running it in the crawl space below my living room.  My best sounding sub configuration turned out to be 2 subs along the front 16' wall and 1-2 feet in from the front corners along with one sub along each 23' side wall, about 1-2 feet away from the rear corners.
    I've never had a room frequency response analysis done for my room but bass response is exceptionally and consistently good throughout the entire room.  
   So, in my experience and to answer your question, 2 subs with room correction do not equal the bass performance quality of 4 subs either with or without room correction.  4 subs will provide an increase in a sense of effortless bass with increased detail and improved bass dynamics.  These improvements will also be present throughout the entire room, not just at a predetermined sweet spot.  
     Each individual needs to decide whether or not these bass improvements are important to them.
  Tim

noble100

I don’t really understand what is meant by pressurizing the room. Can anyone please explain this physical process and its benefits?
I do, however, understand many of the terms and concepts involved related to achieving very good bass response in a given room.

Yes Tim its clear from what you wrote that you do indeed have a good grasp on the situation. Having read everything here its apparent a lot of others would do well to read through your comments carefully, and more than once. And then go and read the referenced work as well.

This is something I’ve been studying for quite a long time, going back to when I built my first transmission line (Roger Sanders, published in Speaker Builder) back in 1980. Like most things I don’t work on it consistently but in fits and starts, which I just happened to be doing recently, and so was really good timing coming across your Swarm experience here. One sold last October and if another one comes up I am on it, otherwise will probably be ordering new some time later on this year.

Pressurizing the room is kind of descriptive but ultimately misleading. The only way the room could truly be pressurized is a closed room with speakers mounted in the walls. Even then it would only be pressurized when the drivers were moving into the room, depressurized when they move the other way. And even then there would still be the time it takes for the waves to propagate. There would still be nodes and anti-nodes.

A lot of what we read about acoustics is like that, descriptive in a way that makes sense, sort of. Actual experience though, like you have with your Swarm, there is nothing like it for turning abstract idea into concrete reality.

Like, we all talk about this stuff with regard to bass, when in reality its not only bass but all frequencies. With bass its in your face obvious. But its across the board.

My listening room is a standard rectangle- 17x24x9. No odd shapes and when first built nothing in it, no furniture, no carpet, no nothing. At one point in fact it didn’t even have sheetrock! I had the unique experience of hearing this space go from framed up to fully treated, and everything in between.

At one point the only "room treatment" was the carpet. Playing a CD with test tones you could clearly hear the distance between the nodes! As the frequency increases the node spacing decreases, some of them down to a few inches, something you can easily hear if you’re ever in a plain room like this. Clap your hands, you could hear it echo back and forth real fast- and even hear the difference between the fast echo lengthwise and the really fast echo crosswise!

Same thing with bass of course, only as you know the wavelengths are so much longer. So one wave doesn’t even have time to generate a full cycle before it could start getting canceled by its own reflection.

Another thing, almost always the talk is about the speaker location. As if that’s all that matters. When in reality (and as you so clearly understand) listener location matters just as much. Anyone who has ever had the experience I have had, of being able to stand where you cannot hear anything at all, then move your head just a very small amount and its loud, would know this. Its not abstract. Its reality.

This is why the Swarm concept is so patently obviously correct to me. Any one speaker/listener setup can never get us where we want to be. It has to be a combination. Its simply physically impossible to eliminate the nodes. So don’t even try. Instead, make enough small ones to seem smooth.

Brilliant.

I have a couple of 12" woofer SVS subs and like them.  I think an important consideration is whether you want a ported or sealed box design.  I have the sealed box, and truth be told I bought them because I read this is what was the best for 2 channel use.  My system is 2 channel, but it is also hooked up to my video set up.

Just like purist believe a preamp should not have tone and balance controls, they believe sealed box is the way to go.  But I have to admit nowadays that I wish my preamp had tone and balance controls and MAYBE that my subwoofers were ported, to have that "explosive" quality, now and then.

This can always be tough, as you’ve already noticed. The variables are great when maximizing your ROI and the overall acoustics, not to mention personal tastes and your “ear”.

I’ve owned many subs... But will continue to invest in SVS’s SB-16 Ultras (until the next revolution 😉). Had a tough time between JL Fathoms, but in the end the SVSs put a smile on my face every time I listen to 2-channel or a movie. 

I still have the 3 Martin Logan subs it replaced, but I no longer use them unless no one is home, and I can’t see neighbors cars across the street. 

Enjoy the journey! 

It’s interesting to see so many different opinions. The product reviews online are all over the place too. Right now I am getting a good deal on an Earthquake supernova MKIV 15 inch for $625 and an NHT CS-12 for $500. Just lost a great deal on a REL T9i this morning for $300. I’d like to keep myself under the $600 budget - would have definitely opted for the REL’s. But so far it’s the Earthquake and NHT that I need to decide on. Any suggestions - maybe I wait and don’t get either. Thoughts?