Choosing Sub-woofers. Please advise ASAP.

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.