Choosing Sub-woofers. Please advise ASAP.


Finally, I have committed to the new home theater system and need sub-woofers. My listening and theater space is about 16' x 14' but then total open space (kitchen in the back) is 16' x 32'. I would like to listen to non-dealer advise. Thank you.

Mcintosh MX160
Mcintosh MC1.2Kw x 2
Mcintosh MC205 x 2
Wilson Audio Alexia - Front Left and Right Speakers
Wilson Audio Mezzo - Center Speaker
Wilson Audio Sophia - Side and Rear Surround Sound Speakers
Origin Acoustic D88 - Atmos Speakers

I like the REL and the JL Audio but JL Audio is my primary choice. The question is 2 x 12" or 2 x 10" or single Dual 12"? The stereo dealer told me 10" would blend in better with music while HT dealer says 12" will have better effect because even my listening space is mall but overall room is large.

Your thought please? I need decision by tomorrow so I can close the final piece. Thank you.
sautan904
In case anyone is interested, here's a professional review of the distributed bass array system I posted about earlier on this thread:
   
AudioKinesis Swarm Subwoofer System | The Absolute Sound

 This is actually about Duke Lejeune’s Swarm system but it’s virtually identical to James Romeyn’s Debra system that I own; exact same 4 (1 sq. ft. footprint by 2 ft. tall 4 ohm) subs with 10" drivers, 1,000 watt class A/B ampifier along with the exact same setup procedure and wiring method.

Tim
David Gage of Deep sea sound makes the best Sub that i have ever heard .
He happens to be right here in my town of Knoxville,TN.
I have had the  MARIANA 24SC 24" SUBWOOFER in my house   for a Demo.
Unreal clean output to about down to 6-7 Hz in my room.
Right now i think they are one of the best subs out there, period.
http://www.deepseasound.com/collections/all
http://www.deepseasound.com/pages/contact

I personally love how Richard Vandersteen goes about making his subs. Both the WQ as well as his newer high end one that goes with the 7mkII's or any other higher end speaker you may be using.  Matches so well with other top end full range speakers.  
dlcockrum,

   You were right, that thread did keep me busy for a while.

    Unfortunately, I still feel the spirit and will likely continue to be a DBA (Distributed Bass Array) system disciple and spread the 'good word' about how well they perform compared to the use of 3 or less conventional subs no matter their quality or cost.

    I may be on a mission from the audio gods.

Thank you for being my enabler,

           Tim
Tim, that may sound best for you and that's awesome. We all have our passions in audio, but to make some of the statements you make are not correct.  There is not scientific measurement to say any speaker or sub is the best way to do it.  There are many ways to do things and listening is subjective as we are all built differently. That can't be refuted.  

There are plenty of products in audio that test great, but sound like crap.  Some do sound good to many folks and measure adequately.  I rarely see products liked that measure poorly.  From the looks of it, you can mention ten different high end subs and they all go about things differently.  You like an array of subs, some else likes fewer or another design or Vandersteen's taking the signal off the main amp (my favorite).  Size certainly does matter if you want to move air (that part is physics and isn't subjective).  

Lot's goes into it and no matter how much data you may present and how passionate you are, it doesn't make you more correct than the folks who espouse REL or JL or Vandersteen or any of the numerous other subs.  The irony is that you are pushing your subs, but you have turned off more than a couple of folks and I'm sure that's not your intent.  Just invite folks to audition and make up their own minds.  
ctsooner,

  I agree with much of what you posted: listening is subjective, audition and make up your own mind and some other statements.

  However, I think you have a misunderstanding of the main points I'm trying to convey. I'll attempt to clarify.

      The main thing I'm espousing is the concept of the Distributed Bass Array System  (DBAS as an acronym).  Specifically, the use of a minimum of 4 subs that are precisely positioned within a room in a progressive locating procedure in order to significantly reduce the bass standing waves throughout the room.  The result being excellent bass response, with no bass peaks (bass overemphasis), bass nulls (bass under-emphasis) or bass cancellations (bass absence), throughout the entire room and not just a single 'sweet spot'.

     What I am definitely not espousing is a certain brand or model of sub.  I know there are many very good subs because I've heard many of them.  Rel, JL and Vandersteen come immediately to mind when I think of some of the best I've heard but there are other very good subs as well.

     An important aspect of deploying a DBAS is that it can be done with virtually any make and model of sub preferred; the only restrictions being that 4 are required and they need to be precisely positioned within the room.  Good DBA systems are truly sub agnostic.

    The concept of the DBAS is typically credited to two acoustical experts, Dr. Geddes and Dr. O'Toole, who have written white papers and conducted empirical experiments on the subject.  I can provide links to their work if you'd like.
     The gist of their findings is that bass peaks, nulls and cancellations continue to be reduced within a given room as more bass sources (subs) are added.  
     They realized there is an obvious practical limit to the acceptable number of subs in a commercial or home environment. Critically, they discovered that the use of 4 subs strategically positioned eliminated the vast majority of bass standing waves within a given room, with additional subs being only marginally effective.  This is the reason most DBA systems utilize 4 subs.

     You're correct, my intent is not to offend anyone or denigrate their preferred sub.  My intent is only to bring awareness to how well the DBA concept works and the fact that absolutely no microphones, room analysis/room correction software or room treatments are required.

     I hope I've clarified my position,
          Tim   
Tim, I agree with you on using multiple subs.  The problem becomes that in order to do it, you MUST place them in exactly the correct positions. If you don't, you lose everything you are trying to accomplish. It also is very costly when you start using top quality subs. You can't get better sound using multiple subs if the subs you are using aren't the same quality as two great subs.  Can't fix what's wrong by just adding more of the same (not talking about anyone's subs specifically).  

In discussing this with a designer, you need a dedicated room typically to make this realistic.  There is no affordable way to do multiple subs when you are talking about high end systems.  You also need to keep in mind what main speakers you are augmenting when using subs.  So many folks don't realize this.  I think that's why I posted what I did. Again, i'm sure your subs are outstanding, but 95% of us can't put 4 or more subs in our rooms, especially where they must be placed.  I've heard arrayed subs in show rooms in the past and loved what I heard. I specifically remember hearing them about 10 years ago in NYC at a high end store, but I hated the mains they ran them with, but it cleaned up the bass a great deal.  

Yes, I like how Vandersteen runs his subs by taking the signal from the mains the way he does and crossing over where he does do the sound of the bass is consistent with the sound of the main speakers. I also like the idea of having a semi active speaker like the Quatro on up.  If done properly, it also will relieve the main amp from having to run anything from 100 or so down and that helps the amps sound better as they aren't having to deal with the bass load which is very difficult for any amp.  Lot's more dynamics current available for the mids which folks don't realize is where a ton is needed on transients.
ctsooner,

     
     As you heard at that high end store in NYC, distributed bass array systems work incredibly well.  They provide excellent bass response that is capable of being taut, textured, detailed and nuanced while also capable of going deep and powerful when the content calls for it.  Because of this, how they integrate so well with any quality or type of main speakers and work in any room no matter the size or shape, I consider them an extremely good bass reproduction system.  

       However, DBAs are not perfect.  A minimum of 4 subs are required to achieve this great bass response throughout the entire room.  Individuals must also make a few decisions before deciding to deploy a DBA in their room:

1.  Do they want great bass response throughout the entire room or just at one optimized listening position?

    The use of 1 or 2 good quality subs can be utilized, if positioned properly, to achieve very good bass response at a single listening position in a room typically called a 'sweet spot'.  The compromise of this approach is that bass response will not be good at numerous other locations in their room due to bass standing waves at those locations. The bass will sound exaggerated, under-emphasized or even nonexistent at these locations.
      The use of 4 or more subs in a DBA is the only currently known method that has been empirically proven to achieve very good bass response throughout an entire room.  
     The choice and ramifications are clear, either you find a way to accommodate the extra subs or you settle for very good bass response at a single sweet spot.

2.  Do they want a very good complete DBA system (like the $3K Swarm or Debra) or do they want to create their own custom DBA  (using 4 even higher quality subs of their own choosing that will be considerably more expensive)?

     I know of only one person, another Audiogon member enginedr1960, who created his own DBA using 4 Rel q201e subs.  He says it's working very well but I haven't heard it and he has never heard the Swarm or Debra DBA.

     I'm completely satisfied with my Debra DBA for both 2-ch music and HT.  However, I would think substituting other high quality subs in a custom DBA would likely sound as good or even possibly better.  Verrsatility is just another of the many benefits of the DBA approach.

     Yes, I am biased but only because I know it works so well.

     Tim  
there really is no difference in this than there is for setting up speakers properly.  It's all about perfect set up and using the best quality subs you can.  The problem is that some folks will read what you post about how great it is and then assume they can use any sub and get great sound. This isn't how it works.  You can not get an inferior sub to sound better than a great one because of this set up.  You still need great sounding subs that can be set up like this.  

I think it's awesome that you love your sub set up.  I haven't hear the subs, but if you are getting 4 sub 1000 subs for 3k, I have to wonder if they will sound better than a pair of 1500 ea subs that are better quality (not all 1500 subs will be better quality, just making a blanket statement).  My other point is that most folks I know well could never have 4 or more subs regardless of size (and size does matter big time) in their rooms.  Life factors intervene as I posted above. Not debating the quality, just the cost, difficulty to set up perfectly and the ability to fit that many in their listening area (logistics).  That's all.  Not debating at all.  
ctsooner,

     I forgot to respond to the last part of your post where you stated:

" Yes, I like how Vandersteen runs his subs by taking the signal from the mains the way he does and crossing over where he does do the sound of the bass is consistent with the sound of the main speakers. I also like the idea of having a semi active speaker like the Quatro on up.  If done properly, it also will relieve the main amp from having to run anything from 100 or so down and that helps the amps sound better as they aren't having to deal with the bass load which is very difficult for any amp.  Lot's more dynamics current available for the mids which folks don't realize is where a ton is needed on transients."

     I don't disagree with anything you said.  I think your point about reducing the main amp's bass duties so they can sound better and have better dynamic range is important.
      I've never actually heard the Vandersteen Quatros but, from the pro reviews I've read and from your comments, I consider them very high quality speakers.  I'm glad you're enjoying them and I have no desire to convince you of anything except the benefits of a good DBA.  
     In fact, with a powered sub already existing in your room inside each Quatro,  perhaps you would only need 2 more subs to reach the required 4 sub minimum for a DBA in your room. A pair of carefully positioned Vandersteen WQs,  combined with the pair of subs in your Quatros, may result in a very high quality DBA in your room.

     I chose a somewhat different approach in my room.  I read some information from acoustical engineers that suggested, for best reproduction of the entire audible frequency range, any system should be constructed based on how various sound wave frequencies will interact with the room.  They explained how bass sound waves interact and propagate within any given room very differently from how mid-range and treble frequencies do so.  Basically, the lower the frequency the longer the sound wave produced. All sound waves are going to be reflected by room boundaries (walls, ceilings and floors).

     The only known and proven method for significantly reducing bass standing waves caused by the very long bass frequency sound waves reflecting off room boundaries and crashing into each other is the use of 4 or more bass sources (subs) in a DBA system.  This will provide very good bass response throughout the entire room.
      Unfortunately, the much shorter mid-range and treble frequency sound waves also bounce off room boundaries and cause standing waves.  But there's currently no known method for significantly reducing mid-range and treble standing waves so that very good mid-range and treble frequency response can be achieved throughout the entire room.  
     The only currently known solution is to optimize mid-range and treble response at a single listening position or sweet spot.  This is done via speaker positioning and angling as well as room treatments (absorbing and diffusing  panels) at critical reflection points.  The goal being that direct mid-range and treble sound waves launched from the speakers arrive at the chosen sweet spot location before (even milliseconds before) the reflected sound waves arrive.

      Because of the above, these acoustic engineers advise constructing a system from the bottom up.  First get the bass foundation right by installing a DBA consisting of at least 4 subs.  Then get the remainder of the frequency range right by installing your speakers of choice and optimizing their positioning and angling and room treatment for a given listening position 'sweet spot'.
     
     I followed this advice, installing the Debra's 4 subs for optimized bass response first and then positioning my Magnepan 2.7qr panels for optimum mid-range and treble response at my listening position.

     This works very well in my room and your method seems to be working very well in your room.

     We both did well!  
     More than 1 way to skin a cat, right?

  Tim   
Hi ctsooner,

You stated: 
" I think it's awesome that you love your sub set up.  I haven't hear the subs, but if you are getting 4 sub 1000 subs for 3k, I have to wonder if they will sound better than a pair of 1500 ea subs that are better quality (not all 1500 subs will be better quality, just making a blanket statement).  My other point is that most folks I know well could never have 4 or more subs regardless of size (and size does matter big time) in their rooms.  Life factors intervene as I posted above. Not debating the quality, just the cost, difficulty to set up perfectly and the ability to fit that many in their listening area (logistics).  That's all.  Not debating at all. "

     It is true that the Swarm and Debra DBA systems are reasonably priced at $3,000.  You get four small (1ft x 2ft x 2ft) but substantial (67 lb)  bass reflex  4 ohm subs with spiked footers and 10" drivers along with a 1,000 watt class A/B sub amp.  I consider these systems bargains given their price and performance.

     In my experience and room, the Debra system clearly provided better bass than my former 2 good quality older Kinergistics 12" subs were capable of.  My opinion is that either the Swarm or Debra four sub systems are likely to provide better bass in most rooms than the use  of  just a pair of subs no matter the price or quality.  I have not actually compared my Debra system to a pair of very high quality subs but would seriously doubt a pair would sound as good unless they were positioned to optimize bass at just a single sweet spot.

     Would the Swarm and Debra's bass performance  be improved upon through the use of 4 even higher quality subs  in the $1,500 plus price range?  Yes, I think this would further improve the bass performance of a DBA commensurate with the performance level increase of the substituted subs.

     I'm very curious how using 4 very high quality subs would sound in my room but I'm in no hurry to spend the thousands of dollars necessary to find out.  I'm currently very satisfied with the Debra's bass performance in my system with the supplied subs.  My concern with spending more in an effort for further improvement is the always present 'law of diminishing returns' in this hobby.  My opinion is that improvements would not be dramatic but marginal in nature and likely be hard to justify given the large expense.

     As to the point about most people not being able to have, or be allowed to have, 4 subs in their room, I consider this the most likely reason for the reluctance of many people to even try a DBA.

      I understand this concern all too well.  My wife thought I was nuts and we both thought we'd have to rearrange our living room to accommodate these 4 subs even though they're relatively small.  But I'm somewhat devoted to the performance of my combination music and audio/video system so I was persistent and managed to convince her to let me give it a try.
     Fortunately, I was able to position each sub where it sounded best while keeping their physical presence disguised (the front 2 hidden behind each of my 6' x 2' panel main speakers and the rear 2 partially hidden, 1 behind a leather chair and the other behind a large end table).

     Of course, not everyone will be able to locate 4 subs in their room as discreetly.  If this is the case,  each individual must determine how important very good bass response throughout their entire room is to them.  Those who think it's important will find a way to accommodate 4 subs.  Those who don't will need to use 2 or less good subs and settle for good bass at only a chosen single sweet spot.

Tim
Sounds like a plan Tim.  As for using subs with the Quatros, there is no reason to do so.  That's the whole idea of his 11 band EQ built into them.  It's the same thing with his 7's.  He had just come out with subs for folks who have to have more bass with the 7's.  In order to get even more bass into the 7's cabinet you need to go external.  Physics says in order to move more air, you need larger cones or even more drivers.  I haven't hear the 7's with subs, but I will eventually.  Just waiting on a dealer to get them.  
Hi ctsooner,

     I understand that each Quatro speaker has a built in 11 band EQ for their built in self-powered sub.
     I assume you position each of your Quatros so that you achieve the best mid-range and treble response, along with the best sound stage illusion, at your listening position. I don't believe you're also positioning each Quatro for best bass response or even if it's possible to optimize bass, mid-range, treble and sound stage at one listening position even with the 11 band equalizers.  

     Because the built-in subs are located at the bottom of each Quatro just below the attached mid-range and treble drivers and it's known that bass sound waves interact within a room very differently than mid-range and treble sound waves interact within a room, I'm not understanding how it's possible to achieve optimal full frequency response at your designated listening position.  Can you explain how you do this in your room  without the ability to locate the bass drivers independently from the mid-range and treble drivers?

     I think you're only option is to position your Quatros for optimum mid-range, treble and sound stage performance at your listening position and hope the bass is also good with the subs in the Quatros at the same positions.  
     Do you just adjust the bass through adjustments on both subs' 11 band EQs and use trial and error? The supplied amp with the Debra DBA has an equalizer, too, but I have never felt there was a need for any EQ in my room so I just leave all bands set at 'flat'.

     If the EQs are your only bass adjustment method, I think your system is likely to really benefit from the addition of a couple Vandersteen QW subs(or their newer subs coming out).  Positioning these extra 2 subs might be a bit tricky since the existing 2 subs in your Quatros can't really be re-positioned.  
     However, I am not ruling out how effective 2 additional subs could be in your room even with the position of the first 2 subs' positions being set at their current position.  I think If the positions of sub#3 and #4 are positioned according to the standard progressive setup procedure used for the Swarm and Debra bass systems, you're likely to notice a substantial increase in bass performance at least at your listening position and possibly throughout your entire room.

    You seem very pleased with the bass and overall performance of your high quality Quatros.  But I hope you'll arrange a demo of this custom DBA at least give it a try in your room with your dealer. I'd be very interested on your thoughts on the results.


Good luck,
  Tim        
av123 mfw-15 hits frequencies that shake my entire house. I had no idea this sub would produce what it does.
Tim, I won't be bringing in any subs once I get the Quatro's in the house and set up.  What you also should keep in mind is that any of the powered Vandersteen's are set up for the best upper bass to treble response and soundstage.  Yes, that's right on their site I believe.  That said, dialing in the built in bass units using the EQ on each will give you probably 99% (always subjective) of what you would get by adding two more 2W subs and dialing them all in.  The dealer is doing the set up for me as most do.  They will use their lasers and tape measures, but they also have a special Vandertones disk they use to set them up for the bass.  It's really easy to dial in your bass this way.  All speakers are designed with omissions and have to be due to limitations set at price ranges or just due to materials available.  That said, I've never heard of a current or former Vandersteen owner from Quatro up complain about the bass.  I have a lot of friend who have standing wave problems, etc... get them in their room and be very very satisfied.  

Again, would adding two more be better?  Only if they match the speaker and are of the same design as the ones already in the room (in Vandersteen's case, using their 2W or better yet, his newest sub).  
Hi ctsooner,

     " That said, dialing in the built in bass units using the EQ on each will give you probably 99% (always subjective) of what you would get by adding two more 2W subs and dialing them all in.  The dealer is doing the set up for me as most do.  They will use their lasers and tape measures, but they also have a special Vandertones disk they use to set them up for the bass.  It's really easy to dial in your bass this way."

      For your sake, I hope you're right.  I do think the dealer should be able to optimize the Quatros' bass performance or optimize the Quatro's mid-range, treble and sound staging performance at a single listening position that you specify in your room. The difficult part will be doing both without compromising the performance of either. The lasers, tape measures, Vandertone disk and sub equalizers may help in this effort but the unavoidable laws of acoustical physics cannot be avoided even by the most skilled Vandersteen dealer.following the manufacturer's best setup procedures and using the most advanced tools in existence.

     My main point is simply that optimizing mid-range, treble and sound staging performance while also optimizing bass performance at a single listening position is not a simple process in any room.  This is especially true when the bass, mid-range and treble drivers for the system cannot be independently positioned in the room.  

     It is well known that bass sound waves propagate much differently in any given room, no matter its size or shape, than mid-range and treble sound waves propagate in the same room.  This is not a matter of opinion or debate.  It has been empirically proven time and again by independent acoustical experts utilizing controlled environments and following scientific methods.  

     These acoustical facts, unfortunately, equally apply in all rooms, including yours and mine.
     As long as the drivers launching bass, mid-range and treble sound waves into a room are positioned in the same speaker cabinet, the capability to optimize the reproduction of the entire frequency range in any room utilizing only 2 of these cabinets/speakers will be highly unlikely.  

     My opinion, based on personal experience and acoustical science, is not meant to disparage the Vandersteen Quatros..  I'm almost certain they'll be able to be positioned in your room to reproduce excellent mid-range and treble performance and an excellent sound stage at your listening position.  However, I'm fairly certain that your bass response at this listening position will not be optimized until 2 high quality subs, that can be independently positioned in your room, are added to your system.

     I believe a better design for the Quatros would entail 2 smaller towers containing the mid-range and treble drivers along with 4 small separate cabinets each containing one of their powered subs.  

     The Vandersteen dealer would first position the 4 independent subs in your room to optimize bass response in your entire room. The equalizers in each of these subs could be eliminated to save costs since I don't believe they would be needed in the resulting distributed bass array system.  
     The final step would be to position the 2 smaller towers to optimize mid-range, treble  and sound stage performance at your preferred listening position. 

     Assuming I think correctly that Vandersteen is unlikely to heed my design advice,I believe the next best option is to add 2 small but high quality subs instead.
  
   I wish you the best,
        Tim  
What you completly fail to understand is that 99% of anyone, will not be able to use 2 other cabinets in their room, especially since they too have to be placed in specific positions based on your theory.  It's not realistic. I"m happy that you have the ability to do it, but I'll take my Quatro's which sound better to me than anything under 30k.  The bass is outstanding.  

The other problem you may agree with, but gloss over is quality.  Bass is by far the most expensive part of the equation and just because someone can afford two extra subs (if they have built in subs which most in the US don't), doesn't mean they can afford outstanding quality subs in order to get better bass. If inferior subs are used, then the bass will suffer much more than just using dual subs that are built in.  That's too is reality.  Doesn't matter how many boxes you use to smooth things out, if it's not top quality, it will sound like garbage. 

I've never heard any aftermarket sub sound great with a Vandersteen than his own. That said it would still be an extra 5k I guess to get two more (that I can't fit into my room for many reasons).  At that point, I'd much rather put that towards better source as I already have 99% of the great bass that my active speaker offers.  

You can make as many posts as you want telling us how great 4 subs will sound and I agreed with you with the caveat that I post again in this thread.  I'm thrilled that you love a specific set of subs. That's honestly awesome and what we all love this hobby.  You can talk about what great quality the swarm subs are, but I'm highly skeptical that they would be up to the quality of most of the subs folks are talking about in this thread as cost is a factor, especially when building bass as it's just hard to do properly and very expensive.  


ctsooner,

 " What you completely fail to understand is that 99% of anyone, will not be able to use 2 other cabinets in their room, especially since they too have to be placed in specific positions based on your theory."

       I'm beginning to feel like we both just completed our first lap in our ongoing discussion on Choosing a Subwoofer and we're heading back into turn #1 to run lap #1 all over again.  

      I don't know about you, but I'd rather not rehash points we already made in previous posts on this thread.

     I think we've both  already made our viewpoints on choosing a subwoofer clear.  

     I'm going to excuse myself from this thread by making a few additional points and summarizing my thoughts on this subject for posterity:

DBAs using a minimum of four subs have been scientifically proven to work incredibly well in providing excellent bass response in virtually any room of any size or shape.

Complete DBA systems, such as the Audio Kinesis Swarm and Debra systems, offer very good bass response at a relatively affordable price of about $3K.

Custom DBA systems can be created by anyone using four even higher quality subs that they prefer.  However, these may be considerably more expensive with possibly only marginal improvements.

If state of the art (SOA) bass response is sought, a DBA using at least 4 subs is required.

Those numerous Audiogon members and others that believe achieving great bass response is just a matter of finding the right brand or model sub and using 1 or 2 in their system will continue to be disappointed in the results not because their chosen sub is not good enough but because they used too few of them. 

Any bass systems not utilizing at least 4 subs will be a compromise according to acoustical experts and my personal experience. Systems using 3 or fewer subs may perform sufficiently well to satisfy their owners at a single designated listening position but allow too many bass standing waves to exist in their rooms to qualify as a SOA bass system.

Properly setup DBAs result in consistently very good bass response throughout the entire room, not just a designated sweet spot.  This makes it an ideal solution for HT use with multiple seating.

ctsooner has claimed that 99% of people will not be able to accommodate 4 subs in their rooms.  99% smells suspiciously to me like a POOMA number; a number ctsooner would likely admit under oath that "I pulled out of my ass". 

Anyone unable or unwilling to accommodate 4 subs in their rooms will, unfortunately, have to settle for less intrusive solutions that will have lower quality bass performance.

Those who are serious about attaining SOA bass performance in their rooms will find a way to accommodate the 4 required subs. 


 The distributed bass array (DBA) method was initially a theory proposed by 2 acoustical physics PHDs, Dr.  Geddes and Dr. O'Toole.   These 2 experts subsequently conducted scientific experiments that validated their theory and published a White Paper detailing the theory, testing method,  results and conclusions.  The gist of their primary conclusion was that bass standing waves, in a wide variety of room sizes and shapes tested, continue to be reduced as more bass source points (subs) are added.  They state that the majority of bass standing waves were reduced at the point that 4 subs were operating, with additional subs only having marginal affect.  

     As their results were consistently duplicated by other acoustic experts via independent scientific testing, the use of DBA systems to provide excellent bass performance in virtually any room transformed from a theory into a  proven and universally accepted solution among acoustic experts.

     I stated the above facts to make it clear that the DBA method is not 'my theory' but a theory proposed and proven valid by a couple of PHD acoustical engineers.

     Okay, I believe that summarizes my current thoughts on subwoofers and bass systems.  

    I wrote this likely final post on this thread with the intent to share with current and future thread readers what I've learned and the solution I ultimately discovered on my long journey to achieve excellent bass response in my system in my room.

    I hope this viewpoint will benefit others on a similar search.

Thanks,
   Tim   
Hi Tim you know you can lead a horse to water but you cant make him drink . All i can say my system for the last 3 years was a DSP controlled stereo sub set up I thought I had good bass at least in my one listening spot . Now after hooking up two more REL subs I have great bass all over the room . The rule is three is mandatory and adding the fourth is the end game any more and its a waste .    
Hi enginedr1960,

  "Tim you know you can lead a horse to water but you cant make him drink "

  Exactly right.  My sense is that many agree with the DBA concept and want really good bass response in their rooms  but find it difficult to drink/accept the 4 subs in their rooms.  Understandable but you seem to have found a way to fit 4 Rel subs in your room and you're now enjoying the benefits of a custom DBA.  Which Rel subs are you using? 

  " The rule is three is mandatory and adding the fourth is the end game any more and its a waste ."    

     Have you tried using 3 subs in your room?  I went directly from 2 to 4 in my room and never even tried 3.  I know Dr. Geddes mentioned the use of 3 subs in his White Paper and I'm curious how close you found the results of using 3 subs came to the use of 4 in your room.

     I'm very glad to know at least 1 fellow Audiogon member has tried the DBA system and has firsthand experience with how well it actually works.

Congrats and enjoy,
      Tim 
Tim, you can't say that we can't talk about something again, because you don't want to.  That is a major part of my point. I agree that 4 subs is optimal.  You said you were out after your last thread that was pretty long.  Then you post again, so I guess you are still in??  Either way, it's not big deal.

Bottom line is that I have been asking a lot of my audiophile friends if they'd use 4 subs in their systems. Many have active Vandersteen's and they said they would't be able to fit them into the room due to many domestic reasons.  If you have full control over your room and feel you need to spend the extra money, that's awesome. Most don't.  Simple point and hard to argue against regardless of it sounding better.  

Not even really disagreeing with you too much. Only on a few points.  
Tim, I know we are.  Wish I could get another set of subs, but I doubt I"ll need to.  :)  
Hi ctsooner,

    You know my thoughts but it's, of course, your choice.
     I hope your system sounds great to you no matter which direction you decide upon.

Later,
 Tim
It will sound awesome.  No doubt.  Hey the Treo's rocked and they weren't even the CT version and had not integrated subs.  No way I'll add any more speakers to the room. Im' trying to get rid of some of the furniture I have built and have in the room, lol.
Hi ctsooner,

   Understood and I hope you report back on your results.

Thanks,
  Tim 
Of course I will Tim.  I will also set that up with Johnny at Audio Connection to see what it sounds like.