Choosing Sub-woofers. Please advise ASAP.

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