Vandersteen Sub woofers v Rythmik Subs

Hi bstatmeister,

Here’s an excellent alternative if you want state of the art bass response and your room can accomodate this system in your room.

http://www.theabsolutesound.com/articles/audiokinesis-swarm-subwoofer-system/

I was considering buying 2 very good subs (Vandersteen, REL or JL) a few yrs ago but bought a distributed bass array system instead based on a lot of in room bass response research I read online and the numerous very good reviews of the Audio Kinesis bass system.
At first listen in my room, I was amazed at the quality of the bass produced and how well it integrated with my main speakers. 2 yrs later, I’m still extremely pleased and I don’t believe 2 or fewer conventional subs would be capable of producing this level of quality bass response in my 23 x16 foot room.
This is a great option if you prefer bass that is tonally accurate, natural but still able to go as deep and impactful as .the recording calls for

There’s only one other person on this forum that I’m aware of who uses a distributed bass array sub system. I forgot his user ID but I remember we both agreed on another thread that it’s hard to overstate how well this concept actually works in our rooms.

System Pros:
-Performs and integrates well with virtually any brand and type of main speakers.
-Performs equally well for both music and home theater sources.
-Gives good bass response throughout the entire room, not just at a single’sweet-spot’.
-Relatively affordable at about $3,000 for the entire bass system: 4 subs and a 1,000 watt class AB amp. About the same price as 2 high quality conventional self-powered subs.

System Cons:
-Requires the space in your room for four 3 foot tall subs with about a 1 sq. ft. footprint.
-Requires a precise and time consuming setup procedure for sequentially locating the exact position of each sub in your room for optimum results. It took me about 2 hrs with a friend assisting to setup my 4 subs. Once this initial positioning process is completed, however, no further work is needed unless you move your system to another room or house.
-Depending on your room, concealing the speaker wires could be difficult. I drilled a hole underneath each sub and hid the wiring in the crawl space underneath my living room. A real pain the ass but probably something I won’t be doing again anytime soon.

Just an alternative option you may want to consider.

Tim

Hi tyray,

     Sorry about detonating your gray matter, I hope it wasn't too painful.  I think, if you just stuff the blown out bits back in your cranium, you should be fine.
     Good bass response is harder to attain in most rooms than good mid-range and treble response.mainly because bass sound waves are extremely long (with deep bass sound waves often being longer than any dimension in your room) while mid-range and treble sound waves are much shorter and more directional.  
     Good mid-range and treble response can usually be attained at a specified listening position by properly positioning your main l+r main speakers and utilizing wall treatments at the first reflection points.  
     In my experience, a distributed bass array system is definitely the best method for optimizing bass response in a given room.  Butt I believe it's still possible for you to get good bass response results in your room by using your single SVS sub as long as you only want to optimize the bass response at a single listening position.
     This can be done using the following method:
1. Hookup your sub and place it at your desired listening position.
2. Play music that has good and repetitive bass.
3. Walk around your room in a systematic manner listening for an exact spot where the bass sounds the best to you.
4. Once this spot is located, reposition your sub to this exact spot.
5. To test results, sit at your designated listening position and repay the same music.
     As you would expect, bass response will be improved as additional subs are added to the room. Of course, there's a practical limit to the acceptable number of subs in a room.  Scientific experiments have consistently proven that  measured in-room bass response only improves marginally beyond the use of 4 subs in a room. 
     This is the reason the Audio Kinesis Swarm system consists of 4 subs.  You could start with your single SVS sub and add subs if you felt the need. I'd suggest following the positioning method I described above for each sub added.

Good luck,
 Tim  
     

"Wow, thanks Tim, I had no idea a product like this was out there and at a comparatively low price to boot. Here are the things I would worry about: the WAF (yep the WAF strikes again for this one)
Integration with the mains - Does it do it the way the Vandersteens do with an external cross-over that lowers the output 6db? Also the Vandersteens keep the signal in the analog realm. Is my understanding of the AudioKenesis that a DSP would be involved to manage the bass? If so, I think that would turn me off. I want that signal as analog as possible.

Hi bstatmeister,

1. WAF- I think the waf, along with concerns about fitting 4 subs physically in their room, are the biggest obstacles most people think of when considering using a distributed bass array system.
I can just describe my experiences with my use of the Swarm and hope it helps you a bit.
I am fortunate in having an understanding wife who also enjoys listening to music and ht through my system. If your wife is less understanding, I’d suggest trying to get her involved with discussing your system and let her make some choices about the music you listen to and the ht you play.
The optimum position of my 4 subs in my 23 x16 foot living room turned out better than I expected, too. Two of my subs are located along my room’s front 16 ft. wall, each about a foot in from each 23 ft. side wall. Each sub is also mostly hidden from view by my l+r main speakers (6 ft. tall by 2 ft. wide Magnepan panels) that are positioned about 3 ft. in front of them.
My other two subs are located along each 23 ft. side wall about 3 ft. in from the 16 ft. rear wall, one on each side. One sub is mostly hidden from view behind an end table while the other is out in the open but my wife likes how it looks like a wooden art gallery pedestal and she usually has a vase full of fresh flowers on it.
2. Mains integration and DSP- The Swarm’s supplied 1K watt class AB amp only accepts l+r unbalanced rca signal inputs and cannot accept speaker level inputs as the Vandersteens can. I don’t view this as a negative, however, since the analog rca inputs result in a seamless integration with my main speakers
There is also no DSP, microphones, room analysis software or digital equalization involved with the Swarm bass system. The signal remains in the analog domain from input to output. But each sub does have its output lowered by 6db by design.

Hoped this helped a bit,
Tim

gdnrbob stated:
" The Audiokinesis swarm makes sense, but then if you could put 4 or more subs of any brand in your room, you would probably get the same result. The whole idea is to balance room aberrations."

Hi Bob,

Correct, a distributed bass array system can be constructed using virtually any 4 subs. The concept is based on the proven theory that multiple generation points of bass sound waves (subs) in any given room significantly reduces the number of bass standing waves existing in the room. This results in more accurate and smoother bass response throughout the majority of the entire room with fewer points in the room that have peaks (exaggerated bass) and nulls (lack of bass).
It’s a choice the user must make: do they want to go all out using 4 of the best subs or a more reasonably priced set of 4 very good but smaller subs that are specifically designed for use in a distributed bass array configuration.
I’ve never heard an ultimate array system using 4 large hi-end subs but would certainly like to.
      After using the Swarm system for the past 2 years, I tend to doubt an ultimate bass array system would sound more accurate, natural or life-like but I do believe it would likely produce more bass. I know I don’t desire more bass either for music or ht in my current system.

Tim

Hi enginedr1960,

     I'm glad you responded on this thread.  And thanks for reminding me that you're the other user on this forum, that I couldn't recall the user ID of, who also uses a distributed bass array system with 4 subs.Your bass system details, experiences and opinions are all valuable contributions to this discussion.

     Your custom distributed bass array system, using the DSPeaker antimode 2.0  to electronically control crossover and room correction, is a bit more complex and sophisticated than my all in one Swarm system that utilizes the sub amp's built in crossover (with my panel mains running full frequency) and precise sub positioning instead of any DSP or room correction.

     I think it's important that readers of this thread realize that very good in room bass response is attainable using either method.  Having no experience using the DSPeaker or room correction of any kind, I know I'm not qualified to declare that either method is superior.  It seems like we both have achieved excellent perceived bass responses in our individual rooms using different methods, with the only common denominator being 4 subs.  

Hi lewnskiH01,

      It's very appropriate that you mentioned Earl Gettes and his advocacy of multiple subs for achieving very good in room bass response in virtually any room.  His research and published white papers on the subject, along with the research and results of Floyd O'Toole and Todd Welti, formed the basis of my understanding and the actual performance potential of deploying multiple subs in a specific positioning method to achieve optimum bass response in any given room.  All of this supporting scientific research was crucial in my decision to buy and use the Swarm bass system in my home music and ht system. 

     However, I have the impression that the OP of this thread, bstatman, may prefer to use a more standard approach to attaining better bass response in his system such as 1 or 2 Vandersteen or Rhythmic subs.  
     If this is the case, I'd just like to say to him that I know it's still possible to achieve good bass response utilizing 1 or 2 conventional subs in his room provided he's satisfied with the good bass response being constrained to a single 'sweet spot'.  I'm certain of this because I've achieved good bass response at a specific listening position using both 1 and 2 good subs in my own and friends' systems.  

     Again, I would caution to use the positioning method I described in my second post on this thread:

1. Hookup your sub and place it at your desired listening position.
2. Play music that has good and repetitive bass.
3. Walk around your room in a systematic manner listening for an exact spot where the bass sounds the best to you.
4. Once this spot is located, reposition your sub to this exact spot.
5. To test results, sit at your designated listening position and repay the same music.
     As you would expect, bass response will be improved as additional subs are added to the room. 2 subs, properly positioned, will give better results than 1.

     In my experience, the Swarm 4 sub distributed bass array system will definitely perform better than either a 1 or 2 sub system. I perceived the 4 smaller sub Swarm system as sounding more accurate, natural, effortless and life-like for music while providing more weight, authority, impact and a bottomless quality to the bass on both music and ht.  These great bass qualities are also now perceived at all 6 seating positions in my room, not just at my single preferred listening 'sweet spot'.

      In retrospect, I believe the Swarm system has been the most significant and unmistakable upgrade I've ever made in my system.  I'll conclude my excessive praise of the distributed array concept and Swarm product by just sincerely claiming I don't think I can overstate how well they both perform.

Tim


      

Hi audioconnection,

     I'm a bit confused by your last post.  You state: " What you guys need to consider is the thinking outside the box.
The Sub 3 nips your particular room overload in the bud with 11 band analog room compensation No DSP processers here.
 With its unique high pass or reliving the heavy lifting of your main amp allows your whole system to improve its articulation, dramatically improving transparency and clarity.". 
     From your description, the new Sub 3 seems like a very nice powered sub  that is a worthy replacement for the now discontinued  2Qw sub. However, I'm failing to grasp why you consider the use of the new Sub 3 as an example of 'thinking outside the box'.since it seems to be a very capable sub that nevertheless would likely be classified by most knowledgeable reviewers as a conventional sub. 
      I would think you would consider, as I do, that the use of a distributed bass array system like the Swarm is a more suitable example of 'thinking outside the box' than the seemingly much more conventional Vandersteen Sub 3. 
     Could you please clarify your statement about 'thinking outside the box' and specifically to which members your comment was directed toward?

Thanks,
  Tim

Hi sonicjoy,

     Very good post with some good points.
    After over 40 yrs of building systems and listening to music in different homes and rooms, I definitely agree with you that every room is different, especially in bass response. 
    When installing a system,  I've recently come to the conclusion that it's best to view a sound reproduction system as 2 separate systems: a bass system and a mid-range treble/sound stage illusion system.  I think having a separate bass system as 4 subs can actually be more useful for achieving best integration and sound if you have the room space.
    The bass is the hardest to get right because the sound waves are so long that they continue to bounce/reflect off all room barriers until they run out of energy.  These sound waves eventually either crash into each other causing standing waves and typically a lack of bass at those points or they piggy-back on another reflected sound wave and cause bass reinforcement and typically exaggerated or boomy bass at these points.  
     Acoustic engineers are able to predict where sound waves will intersect based on the room dimensions, sound wave frequency, barrier material and speaker/sub location(s).
     The beauty of a properly set up distributed bass  array system of 4 or more subs is its ability to eliminate the vast majority of intersecting bass sound waves, and therefore the vast majority of bass peaks and nulls, in any given room.  This not only makes the bass sound more accurate and smoother, the bass response is this good throughout the majority of the room. 
     As you're all too aware, having a small and non-symmetrical  room only makes good bass response more difficult to attain.  I understand you have space and waf issues but I still believe a Swarm distributed bass array system is your best option for achieving state-of-the-art bass response in your room.  
      This system is not as intrusive as some may initially think.  Each sub weighs about 44 lbs., has a 1 sqft. footprint and is 28 inches tall.  Each sub is positioned with the driver facing, and about 1 inch away from, the wall.  The visible portions of each sub(sides, top and back) are made of your choice of high quality wood and actually look quite good and stylish.   Have your wife choose the wood.
      Hiding the speaker wires may be the most difficult issue if you can't run them below the floor or in the walls.

 Just my thoughts-good luck,
      Tim

Hi sonicjoy,

     Okay, thanks.  I'll check out the Acoustic Fields website.

     What's great about the Swarm system, when properly set up, is that it requires no room treatments, DSP, equalization,  or room correction mics and software.  It's really kind of magical how eliminating the vast majority of bass standing waves, and the resultant bass peaks and nulls, in the room results in such excellent bass performance throughout the entire room.  I think it's something you have to hear for yourself to really believe.  It sounds too good to be true when just verbally described.  It really took a lot of research and convincing for me to overcome my skepticism and give the distributed bass array system a try.  But I am so grateful I did and now feel like I owe it to other members to spread the word.
     I think this could be considered a type of room treatment because it prevents bass response issues at the root cause, which is likely a lot more effective than trying to compensate or room treat for the inevitable standing waves once they actually exist in the room.  Bass room treatments are typically much larger and less effective than mid-range and treble room treatments in my experience.  
Thanks,
  Tim

" noble100 ,
I think Johnny was referring to the integrated equalizer in the new Sub 3.
As far as I know, there are no subs with equalizers incorporated."

Hi gdnrbob,

     Thanks for responding for audioconnection/Johnny.  

     I understand audioconnection/Johnny is a home audio retailer with Audio Connect in N.J. that sells Vandersteen products.  He seems to be justifiably enthused about Vandersteen's soon to be available Sub Three.  It appears to be a very nice sub for $2,500.
     However, implying that incorporating a 7-band analog equalizer in the Sub Three demonstrates 'thinking outside the box' is a bit of a stretch.  The truth is that it's basically a conventional sub with an equalizer added.  
     An equalizer will not be able to eliminate, or compensate for, the vast majority of bass standing waves that inevitably result from having a single sub in a room.  With proper positioning, the best one could expect to achieve would be good bass response at the preferred listening position.  This will hold true for all single sub systems, no matter the cost or competency of the single sub employed. 
     As I understand it, analog equalizers such as those incorporated in the Sub Three and the Swarm's sub amplifier are useful mainly in compensating for any bass 'slap' present in some rooms that is caused by the reflection of bass sound waves off the floor and to the ceiling.

     The above is not just my opinion.  It is a summary of the results of years of scientific research and experiments conducted by acoustical scientists Earl Geddes, Floyd O'toole and Todd Welti, among others.  
     These experts state that deploying 2 subs will result in fewer bass standing waves and better bass response in the room.  Deploying 3 subs will further significantly reduce bass standing waves, 4 subs will eliminate the vast majority and any additional subs beyond 4 will only result in smaller incremental improvements  in bass response in any given room.
     However, utilizing 4 Vandersteen Sub Threes would cost about $10,000 while the complete Audio Kinesis Swarm or Debra 4 sub systems both are priced at $3,000 or less and likely are less intrusive.  

     I'd imagine the Sub Threes would definitely produce more bass than the Swarm system but I'm not certain which system's bass would sound best and, if the Sub Three system did sound best, whether it sounds $7,000 better. 
 Tim     
  

" What's the crossover frequency and slope of the Swarm system? I understand the xo is before the Swarm amp and all subs operate in the same frequency range, summing up L & R."

Hi lewinskih01,

   I actually own the Audio Kinesis Debra bass system (a very similar system to the Swarm that I bought from James Romeyn Music & Audio in Utah that he is licensed to sell under the Audio Kinesis brand).  Both systems use the same 1K watt sub amp that contains an active xo with a continuously variable low pass cutoff filter that ranges from 20-200 Hz  that I usually set at 40 Hz.  Sorry, I'm not sure of the slope.  All subs operate flat from 20-100 Hz with 113 db output @ 20 Hz, are 4 ohms, are fed the same l+r summed mono signal, have 10" drivers and can handle 600Wrms. 

     Here'a link to the exact Debra bass system I own:

   http://jamesromeyn.com/old-pages/home-audio-gear/dsa-1-0-distributed-subwoofer-array-5-pieces-4k-usd... 

Tim

" noble100 ,
I would not discount the Sub 3 until I listened to it. If Mr. V. discontinues a very good sub in favor of a new one, it must be a significant improvement.
And, Vandersteen's use of an external high pass crossover was very much 'thinking outside of the box' 30 years ago, so maybe Johnny isn't exaggerating.
I understand the concept of using multiple subs to eliminate/ reduce room nodes, but perhaps integrating an equalizer can achieve something the same. As I have not heard, nor know how they are set up, I can't say definitely how well/badly they work.
Maybe they will be in the store when I get some time to go later this summer-along with some other Audiogon members.
Bob"

Hi Bob,

     It was not my intention to criticize the Vandy Sub Three at all.  I  stated the Sub Three seems like a very good sub for $2,500 and it appears to be a worthy replacement for the very good but now discontinued 2QW.
      My main point was that no single sub, not even the most expensive and highest quality sub in existence, is capable of reducing the majority of bass standing waves and resultant bass peaks and nulls in any given room.  In fact, using only a single sub probably creates a net increase in   bass standing waves in most rooms. 
     Unfortunately, an equalizer is not able to eliminate, or compensate for, the vast majority of bass standing waves that inevitably result from having a single sub in a room.  The only scientifically proven methods to reduce bass standing waves in any given room are either expensive, inefficient and bulky bass traps on the back end or the moderately expensive, efficient and much more effective method of multiple subs in a distributed bass array configuration on the front end.    
     Again, I think the Vandersteen Sub Three seems like an excellent sub.  However,  I also think using a minimum of 2 and up to 4 of them will provide the best results.     
    My motivation is just to spread the word about how well the distributed bass array system has worked for me and how it will likely work for others in their rooms using their choice of subs. Deploying 2 subs is good, 3 is better and 4 is best.
   Tim                             

     If one wanted the finest signal integrity and purity for optimum performance from a music based 2-ch system, is it beneficial to use an amp with non-standard connections,  use multiple connector type adapters and use an external crossover with multiple signal affecting dip switches?
     
     I think we all know the answer to this, right?

Tim

Hello hifiman5

Yes, I understand and agree with you about how relieving the main amp’s responsibility of amplifying bass signals is beneficial both to the amp’s power output requirements and the overall sound since the amp is then able to devote itself to only amplifying the mid and high frequency signals. This should result in a more effortless and dynamic sound for everything above the bass.
I would just suggest that, if the goal is a matching effortless and dynamic sound for the system bass, more than a single sub is the optimum solution..
In my experience, employing a distributed bass system of at least 2 subs, will deliver the revelatory sound performance in the bass that you accurately described for the mids and highs once an amp is relieved of amplifying all bass frequencies.
Again, however, I advise that using just a single sub will not bring bass response closer to this goal, using 2 will begin the improvement, using 3 will continue the improvement and using 4 subs is the magic number that will allow reaching the goal.
I understand if some are skeptical but the results I describe above are scientifically proven via experiments that have been independently verified not only by acoustic scientists but also by regular people who have purchased and deployed distributed bass array systems such as myself and many others.
I’m just trying to spread the word on how well this concept actually works. My initial opinion of the sound results upon first listen remains the same today: it almost magically produces excellent bass without any DSP, parametric equalizing, room treatments, mics or room correction software or hardware.
My only cautions to bstatmeister would be to not just plunk down his single Vandy sub in a convenient spot arbitrarily. He’ll get much better results following my positioning procedure previously described:

1. Hookup your sub and place it at your desired listening position.
2. Play music that has good and repetitive bass.
3. Walk around your room in a systematic manner listening for an exact spot where the bass sounds the best to you.
4. Once this spot is located, reposition your sub to this exact spot.
5. To test results, sit at your designated listening position and repay the same music.

As you would expect, bass response will be improved as additional subs are added to the room. 2 subs, properly positioned, will give better results than 1. Repeat the above procedure for each additional sub you desire to buy and bass response will continue to improve.
I don’t advise using more than 4 subs unless you enjoy wasting your money. Any gains made in bass response in your room beyond 4 subs will be incrementally much smaller than the obviously more noticeable gains made when adding subs #2-4.
CAUTION: Disregarding any of the above utilitarian advice is at your own peril and may result in the forfeiture of all consultation fees you may have paid.

Love,
Tim
XOX

Hi hifiman,

     Another independently verified example of how well the distributed bass array system works.
     I'll start the incorporation process for our new company: The hifiman5 and noble100 Home and Business Sound System Consulting Group.
     Please locate and fully outfit our new storefront location, including phones, computers, staff along with fully operational Vandy and Audio Kinesis showrooms.
     I think a June 1st Grand Opening should be our goal.
Thanks,
   Tim
P.S.  I'll need a 65" OLED hdtv, leather couches and chairs, a fireplace and a hot tub in my no less than 30 x 30 ft. corner office with a view.
Thanks,
  Tim

bstatmeister,

     I'm familiar with unbalanced rca and balanced XLR connections but I've never heard of a TS connector.  

     From the Amazon adapter you linked to, it seems you're 'TS' connector is what I consider a'1/4"'  connector typically used for mics and headhones. 
     I'm assuming your amp acepts l+r mono 1/4" plugs, correct.?  Can you tell us the brand and model of your current amp? 
      I'm not stating you're definitely wrong in calling. a 1/4" plug a TS plug, just that I've never heard anyone refer to a 1/4" plug as a TS  plug.
Thanks,
  Tim  

Hello wolf_garcia,

     " Moving a speaker around is about as analog as you can get, and I like it."

     Since you seem to enjoy experimenting, I thought you might want to try positioning your REL-Q150e at your listening position then walk around your room listening for the spot you think the bass sounds best.  
    It's a very good possibility that locating your Q-150e at the spot you thought the bass sounded best will provide the same bass quality at your listening position.  
     If the spot makes sense functionally and aesthetically, you may be pleasantly surprised at the sound quality.

Just something to try,
   Tim

bstatmeister: "Honestly I would rather buy an extra sub than a cross over - at least to start off with...lol"

    I have no experience with the Vandersteen crossovers discussed but I'm fairly certain that having 2 subs rather than just a single sub in your system, provided both subs are properly positioned, would result in a more significant and obvious overall system performance improvement than utilizing a high quality crossover would.  You could always add the crossover subsequently if you thought there was a need.  

Tim

" @noble100 and others interested in room acoustics: which other fora are you active in?

I'm interested in discussing and posting some measurements (which Agon doesn't allow) and would live to engage others who share that interest."

Hi lewinskih01,

     Sorry about the late reply.  I responded earlier to your question but just realized my post was removed, probably by the moderator due to negative references to our president I threw into my response.
     The other forums I would recommend to you are Audio Circle and  DIY Audio.  I learned a lot on these sites at separate times in the past when I wanted to learn more about class D amps and in-room bass response.  I consider both of these sites to be more concerned with empirical data and a scientific approach than the generally more opinion based discussions on this site. 
      Doing a Google search on "home audio room acoustics" would likely also be useful. 

Cheers!
  Tim

Hola Horacio,

     So, your 'cheers' sign-off does indicate your British heritage but you're now living in Argentina, interesting.
     Yes, I share your interest in room acoustics, have read many white papers from leading acoustic scientists' research and read a lot of various online audio blogs on the subject.  I've learned quite a bit but definitely do not consider myself an expert.
     My main focus has been an attempt to attain the best sound reproduction for 2-ch music and ht in my 23 x 16 foot living room.  I've basically been trying to adapt what I've learned to my room and system. 
     For example, one of the principles I learned was that it's more difficult to attain good bass response in a given room than good mid-range and treble response
.  Therefore, I decided to initially concentrate on attaining very good bass response in my room as my goal.
     The findings of acoustic engineers Earl Geddes and Floyd O'Toole were instrumental in my decision to employ a distributed bass array system to attain state of the art bass performance.  It has been scientifically proven, by Geddes and O'toole and independently verified by others, that bass standing waves are reduced (and bass response improved) in any given room as more subs are added.   
     They also found that bass standing waves will be significantly reduced as subs 2-4 are added and that the vast majority of standing waves are eliminated by deploying 4 subs; any subs added beyond 4 will only result in relatively smaller improvements.
     Because of the above,I decided to purchase and install the Audio Kinesis Debra distributed bass array system that consists of four 1' x1' x28"  44lb. 4 ohm subs with 10" drivers all powered by a 1K watt class AB amp.  
     This system has allowed me to reach my goal of very good bass response in my room as a solid foundation for my system to be built upon.  It not only provided accurate, smooth, textured and effortless bass at my listening position but also at the 5 other seating positions in my room. I believe it's possible to achieve this level of bass response utilizing as few as 2 subs if properly positioned but the bass will only be optimized at a single 'sweet spot' seating position, not throughout the entire room. 
     Once the bass system was installed and functioning at a high level, I found I only needed to independently dial in the mid-range, treble and sound stage imaging and illusion at my listening position.  I have large Magnepan 2.7qr panel speakers and this was relatively easy to do by experimentation with their positioning; distance between the left and right speakers, distance from my listening seat, distance out from the front wall,angling or toe-in and room treatments at the first reflection points.  
     I've come to the conclusion that it's best to treat any sound system as 2 systems: a bass system and a mid-range/treble sound stage imaging system.  I've arrived at this conclusion by research but also by applying this research in my own room and system(s).

Hope this helped a bit,
 Cheers,
Tim 

" Even when a stand up bass is located left in the soundstage, the speakers make the sound come from that position perfectly even though the sub is in the right corner."


Hello mr_m,

     I find this to be is a very interesting phenomena of human hearing that I think is important to realize when we're setting up our systems for optimum bass response in our rooms..
     When I first installed my  Audio Kinesis Debra system, I was concerned how bass emanating from 4 subs arrayed throughout my room would affect my system's sound stage illusion normally spreading from wall to wall and sometimes wider while varying in how many seemingly feet in depth depending on the quality of the recording. 
     These 4 subs are run in mono and I was wondering if I'd still be able to perceive bass instruments as being located properly and precisely within this sound stage illusion.  This very life-like illusion on good recordings is something I really enjoy and didn't want to lose.
     Fortunately, the sound stage illusion was even more palpable and life-like with the Debra in place.  The locations and spacing of Instruments and vocalists within the sound stage illusion were only enhanced.  Even though the bass is in mono and the bass sound waves are coming from 2 subs along the front 16' wall and one along each of the 23' long side walls (about 4' in from the back 16' back wall with my listening seat centered on this back wall),  I always perceive the bass as coming from the proper position within the sound stage illusion at the front of my room on both music and ht.  I  perceive no bass emanating from the 2 subs closest to my seat, just from instruments and voices within the sound stage illusion.   
      I'm very pleased with this bass response and illusion but it is odd how we humans perceive sound; a combination of our ears receiving the sound waves and our brains processing them. 
     I think this affect should be considered as a factor in room acoustics when assembling a home audio system.  I believe this phenomena can be explained by the fact that bass sounds are rarely just bass frequencies and typically have harmonics exist that are at above bass frequencies.  Humans are poor at identifying the location of low frequencies but much better at doing so as the frequencies rise into the mid-range and treble range. 
     I think the scientific explanation is that the higher frequency harmonics of bass sounds allow our brains to better place the source of bass sounds/instruments in the sound stage illusion.  I realize this may be an oversimplification and the actual ear and brain relationship is likely much more complex, but I think it adequately describes the process.

Tim  

" I read so many talking about an array of 4 subs.  that sure can help, but  2 subs are already a big advantage over one and 4 gives flatter response IF the sub has no other way to EQ the problems remaining.  2 quality subs with room EQ will trump most 4 sub systems.  We are also talking a more wife friendly room (I too like a cleaner looking room now days).  Another problem never mentioned is when the subs have drivers pointing into the listening space or ports the sidebands as these have a negative impact on imaging and sound stage.  Again, this is something that is never discussed, but very real."

Hello ctsooner,

     I agree that 2 subs, when properly positioned, will produce better bass response in almost any room than just a single sub.  This has been scientifically proven with the stipulations that good bass response will exist only at a predetermined listening position 'sweet spot' that results only if a specific sequential sub positioning process is followed. This is the proper positioning procedure:

1. Place sub#1 at your preferred listening position and play music with good and consistent bass content.

2.Starting at the right front corner of your room,walk slowly counter-clockwise around the perimeter of your room listening for the exact spot that the bass sounds the best to you.

3.  Place sub#1 at this specific location.

4.  Place sub#2 at your preferred listening position and play the music with good and consistent bass once again.

5.  Starting at the newly positioned sub#1, continue walking counter-clockwise around the perimeter of your room listening again for the exact spot where the bass sounds best to you.

6. Place sub#2 at this specific location.

7. Sit at your preferred listening position and verify the bass response sounds 'excellent' to you; smooth, detailed and natural without any over or under emphasis.  If the you perceive the bass response as 'excellent', then the positioning process is completed.    If not, it is worthwhile to repeat the process since even small errors in positioning can result in less than optimal results.
     With only 2 subs, this process provides excellent bass response.only at the listening position because the positioning process has resulted in no bass standing waves at the listening position. There are no bass peaks (exaggerated bass) or nulls (lack of bass due to cancellation) at the listening position.but standing waves will still exist elsewhere in the room. 
     Following this procedure with a 3rd sub will significantly reduce bass standing waves (improving bass response) elsewhere in the room and adding a 4th will  eliminate the majority of bass standing waves in the room.  In other words, adding the 3rd an 4th sub will not further reduce bass standing waves at the preferred listening position but will elsewhere in the room.  It's the user's choice concerning the extent of state of the art bass they want in their room.  
     I wanted excellent bass response at all 6 of the seats in my combo 2-ch music and ht living room system even though I could only optimize the midrange, treble and sound stage illusion performance at my preferred listening position.  I realize, of course, that not all users will require excellent bass response throughout their entire room.
     Also, I definitely disagree with your statement that "2 quality subs with room EQ will trump most 4 sub systems".  It's my understanding that the only benefit of room EQ in a bass system is to reduce 'room slap' which is typically produced by a sub bass sound wave bouncing/reflecting off a hard floor and then  reflecting rather quickly off the ceiling or wall, causing a sharply perceived sound resembling a slap. 
      The frequency is usually below 300 Hz and often below 100 Hz.  Reducing the offending frequency via a room EQ may reduce the slap affect but will also affect the flatness and accuracy of your bass response in that frequency range; likely more noticeable the higher the offending frequency is.  
     The main reason your statement that "2 quality subs with room EQ will trump most 4 sub systems" is so inaccurate, however, is that a properly set-up 4 sub bass system  requires absolutely no expensive bass room treatments/traps, mics, room equalization and room correction software or hardware. 
     It is a very elegant, almost magical, solution for SOTA bass response in virtually any room and integrates extremely well and seamlessly with any set of main speakers.  It will go as low as the musical or ht content calls for in an effortless manner while still keeping pace and integrating well with the fastest planar-magnetic and electrostatic panel speakers.
    Here's a review of the Audio Kinesis 4 sub system from The Absolute Sound for a more independent and perhaps less biased source: 
http://www.theabsolutesound.com/articles/audiokinesis-swarm-subwoofer-system/

Tim

" We are also talking a more wife friendly room (I too like a cleaner looking room now days).  Another problem never mentioned is when the subs have drivers pointing into the listening space or ports the sidebands as these have a negative impact on imaging and sound stage.  Again, this is something that is never discussed, but very real."

ctsooner,

     Sorry, I went on so long on my last post but forgot to address your final points concerning the WAF and imaging:

WAF- If you view my system photos you'll notice it still maintains a clean look in my 23 x16 ft. room that my wife and I also enjoy.  The 2 subs along the front 16 ft. wall are hidden from view by each of my large 6 x 2 ft.panel  mains.  Each sub along the 23 ft. long side walls are a bit more visible but, because the 10" drivers face the wall,all that's visible is the nicely finished wood  on the sides, top and backof each sub.  My wife says these look like art gallery pedestals and she usually has a vase of fresh flowers on one or both.

Imaging and sound stage illusion-  If you care to read about this I discussed it thoroughly in my post on 6/13 responding to bo1972,  The gist is that, IMO, both are only enhanced with the Audio Kinesis 4 sub configuration that is rated at -3db @ 20-100 Hz.

     The Vandersteen Sub Nine is rated identically as -3db @ 20-100 Hz.  I know the Audio Kinesis Swarm/Debra, and I believe the Vandy, are designed to be -3db to compensate for the typical bass room gain of +3db.

Tim

     When did Vandersteen start positioning, considering and pricing themselves as an ultra high-end company?  I've always considered Vandersteen as a solidly high-end manufacturer that offered very good quality speakers, subs and related crossovers at  more reasonable prices,especially considering  their proven history of high quality offerings.
     I was just checking out the new Sub Nine on their website.  I haven't heard them but from their description and look, they certainly seem like another fine Vandy product.  But I was a bit shocked by the $18,900 per pair suggested retail price.   The very fine Model Seven MKII are also very expensive at $62,000 per pair.They  are now even selling a pair of 600 W@ 4 ohms mono-block amps that have tubed input stages and bipolar transistor output stages (M7-HPA) for $57,200.
     So, if you want the best all Vandy system while optimizing in-room bass response, you'll need the Model Sevens, the matching mono M7 amps along with the extra pair of Sub Nines to optimize the bass response.  This will set you back $138,100 but you'll also get a pair of nice Audioquest  cables gratis.
     Undoubtedly an excellent audio system in almost anyone's estimation but not the better performance than expected for the price that I remember when I was speaker shopping in the early 1980's and auditioned the 4C. 
     I'm not sure if anyone on this thread is seriously considering the Sub Nines but I cannot understand why anyone would pay $18,900 for 2 subs when they could buy the Audio Kinesis  Swarm or Debra bass system with 4 subs that will likely provide better in-room bass response for $2,500 and save $16,400 in the process.  Yes, the Nines may produce more bass but I've never had an issue with the bass quantity ( or quality) with the Audio Kinesis.
     It's similar to what I recall from past Vandy products:; a product that offers better than expected performance  based on the reasonable price. . 
     Anyone know why Vandersteen decided to move away from these type of products, like their former 4C speakers, and toward the more expensive and esoteric?
Tim    

"The 9’s are very special subs in their CF build to their ability to fill large spaces etc... The new Sub 3’s are affordable and have built in EQ as we spoke about earlier. Set up properly, they will smooth out the bass just as good as a swarm or any of the subs.

What the swarm is, can be done with any sub. I personally would rather just get two great subs rather than 4 subs that may or may not sound as good. Just because a sub can be purchased for half of the cost of another one doesn’t mean it will sound nearly as good as the other one.

I have a close audio buddy who auditioned the AK swarm vs many other subs and went with the Vandy 2’s. It’s always a personal choice as we know. Back to listening."

ctsooner,

Based on your comments on this thread, it’s obvious your knowledge of the latest and best scientifically proven methods of producing excellent in-room bass response, and the critical factors involved, is seriously lacking.
You’re failing, or maybe just refusing, to understand that there are currently scientifically proven methods, based on years of research and experimentation by 2 leading acoustics engineers Dr. Earl Geddes and Dr. Floyd O’Toole, that provide sota bass performance in virtually any room.
These methods began as mere theories that require well designed scientific experiments for the theory to be proven as valid. Each scientist is further required to publish a White Paper that proposes the theory, describes the experiment designed to prove or disprove it and the details of the results.
If the theory is proven valid via the experimentation, the next hurdle for each scientist is peer review; at which a panel of fellow acoustic engineer scientists are given an oral and written presentation by the White Paper’s author for the purposes of evaluating, thoroughly understanding and thoroughly questioning it.
Even if the panel ultimately decides to consider the theory as a new empirical fact, the original results of the experiments the scientists performed to prove the theory must be able to be consistently and independently duplicated with the same results for the theory to continue to be considered empirically true and valid.
Okay, I think you now get the gist of how an acoustics theory becomes an accepted fact.
But what theory from Geddes and O’Toole was proven valid via the above process?
The theory stated: Bass frequency response will improve in any given commercial or residential room as the number of devices reproducing the bass sound waves (subs) is increased in that room. The engineers understood that low bass sound waves are extremely long and will continue to bounce/reflect off all room barrier surfaces (especially parallel surfaces such as 2 walls or floor and ceiling) until they run out of energy in all rooms that have room dimensions that are not as long as the low bass sound waves themselves: a 40 Hz sound wave is 28 ft. long and a 20 Hz wave is 56.5 ft. long.
As these long bass sound waves are launched into the room along with subsequent ones, they travel on mathematically predictable paths until they predictably either crash into one another , creating a bass de-emphasis or ’null’, or they merge and reinforce one another, creating a bass over-emphasis or ’peak’.

Of course, this also happens with the much shorter midrange and treble sound waves but these cancellations and reinforcements are distributed throughout the room and typically perceived as adding an ’’airy’ or ’liveness’ quality to the musical sound in the room.
However, with the much longer, low-frequency waves, the cancellations and reinforcements are localized to specific areas in the room. The result is that the bass response of the room is noticeably uneven at certain frequencies—there will be too much bass at a particular frequency in some spots in the room, and not enough at others.
I believe the above leads to the gist of what you’re failing, or refusing, to grasp; that the Geddes and O’toole developed distributed bass array system (AK Swarm and Debra bass system) is a scientifically proven method for attaining sota bass response in virtually any room.
Comments of yours such as "I personally would rather just get two great subs rather than 4 subs that may or may not sound as good" makes it clear to me that you do not realize the significant in-room bass response improvement levels achieved through the use of a 4 sub distributed bass array system when compared to a 2 sub system, no matter how large, expensive, the brand or the competency of the 2 subs.
The primary scientific reason for the fact that in-room bass response improves as the number of subs launching bass sound waves is increased in any given room is caused by the reduction of bass standing sound waves existing in the room. The research proves that bass standing waves are progressively reduced in any given room as the number of subs is increased from 1 up to the experiment’s projected limit of 3,000. Critically, however, the research also proved that the reduction in bass standing waves was most significant when increasing the number of subs from 1 to 4, with any subs added beyond 4 still decreasing bass standing waves but only at a smaller incremental amount.
Obviously, the scientists knew there was a practical limit to the number of subs your wife would allow you to place in her living room. Importantly, they told her to let you put 4 subs in the room since the data showed that 4 subs eliminated the vast majority of bass standing waves and thus provide their version a good balance between bass performance and just getting ridiculous and messing up her room.
Lastly, I just want to add that I respect Richard Vandersteen, his many audio contributions and his products. I have no intentions of denigrating him or his products. 
I also agree with several of your other comments, such as "what the Swarm is, can be done with any sub" and "just because a sub can be purchased for half of the cost of another one doesn’t mean it will sound nearly as good as the other one" . In my opinion, both true statements that don’t require any qualification.
In fact, I have little doubt that a 4 sub distributed bass array system consisting of 4 Sub Nines, Threes or even the discontinued 2Ws would likely outperform the AK Swarm or Debra bass systems.
I didn’t address your other comment of " The new Sub 3’s are affordable and have built in EQ as we spoke about earlier. Set up properly, they will smooth out the bass just as good as a swarm or any of the subs". I think this comment just demonstrates again your failure, or maybe just your refusal, to understand that there are currently scientifically proven solutions for achieving sota in-room bass response, based on years of research and experimentation by 2 leading acoustics engineers Dr. Earl Geddes and Dr. Floyd O’Toole, and that any sort of existing digital or analog equalization has been proven to be completely incapable of duplicating.
I could elaborate but I’ll just leave it at that for now.

Gotta go,
Tim

Hello gdnrbob,

     Yes,I generally agree that everyone is entitled to their opinions; I just prefer a bit of supporting evidence to indicate whether I should value them.  
     My issue with ctsooner is that he seems to have a higher regard for his opinions than the relevant facts and significant difficulty distinguishing between the two. 

Allright,
 Tim  
.  

" @noble100  - why not start a thread on swarm ? I am sure it will attract a ton of interest "

Hello tonic601,

     Very good idea.  I did start a thread on 6/30/2016 titled "Anybody Else Using a Distributed Bass Array System?".  Here's a link to that thread:

https://forum.audiogon.com/discussions/anybody-else-using-a-distributed-array-sub-system?highlight=d...

       That thread did attract a lot of interest for about 7 months even though it didn't specifically mention 'Swarm' or 'Debra' or 'Audio Kinesis' in the title. I recall being a bit surprised, given it was posted on a high performance audio site like Audiogon, that there wasn't  more members using a high performance bass system like the Swarm or Debra.  
     
     I get, however, the gist of your comment: enough already about the Swarm,  go start your own thread and leave this thread alone.
     I understand your perspective and that it may be shared by others on this thread.  It was never my intention to distract from the OP's original concern, only to offer an alternative solution that I know works well.
     I think it's important to respect the viewpoints of others and don't want to be considered unreasonable so I'll bow out of this thread and take your advice to start my own thread 
       It's been over 2 years since I posted my thread and it's very possible that more members have discovered just how well distributed bass arrays work and currently utilize one.  But this time I think I'll actually use Audio Kinesis,Swarm, and Debra in my thread title.
  Thanks,
   Tim

Update:

     Just wanted to follow-up on my last post and provide the link to the new thread I stated I'd start on the Audio Kinesis Swarm and Debra distributed bass array systems:

https://forum.audiogon.com/discussions/anyone-else-using-an-audio-kinesis-swarm-or-debra-distributed...

Later,
  Tim    

@noble100 not running you off, new thread seems to be thriving.... : "


Hello tomic601,

Thanks for the welcoming words. I’ve been monitoring this thread on and off but haven’t felt the need to respond or add anything for awhile.
     I wish I could be of more assistance as to whether Vandersteen or Rhythmic subs perform best but I stopped thinking or caring about which single sub performs best once I learned of the significant advantages of multiple distributed subs.
     I envy you rebuilding a pair of the legendary ESL63and wish you the best in your project. 
     I think I’ve stated enough of my thoughts already but won’t hesitate to respond further if I think it might be useful to the OP or thread readers.

Thanks,
Tim

ctsooner,

I completely agree with you on loving the sound of the Quads, large Maggie panels and the original Apogees.

Interesting that all of these ’fast’ speakers share the common complaint from owners that they’re all very difficult to integrate subs with. The usual complaint is the sub or subs sound disconnected from the main speakers because the ’slower’ subs cannot keep up with the speed of the ’fast’ panels. I currently use a pair of large Maggie panels in my system and tend to agree with the difficulty of integrating subs well with them.
However, I would definitely suggest the Audio Kinesis Swarm,Debra or any custom 4 sub DBA system as an excellent method of seamlessly integrating a sota bass system with any ’speakers but I can verify they integrate especially well with ’fast’ panels.
Because each Debra sub has a 10" long-throw woofer and is only required to reproduce a portion of the total bass, I think each sub is capable of being very agile and, with all 4 working in concert, it results in bass that is very articulate with great definition.that can reproduce the entire range of bass notes incredibly accurately; from very deep and powerful to sharp and taut.
     I believe anyone listening to any DBA system, whether an Audio Kinesis complete kit or a custom system of someone’s own creation, even briefly would be able to quickly recognize the extreme quality of bass reproduced but it’s much harder for me to express in words.

Tim

ctsooner and tomic601,

     I agree with both of you that subs outputting any bass in the 150 Hz range (I would even say any bass of 80 Hz or higher) is directional and can cause issues.  I've experimented with the Debra amp's crossover filter control, adjustable from 10 to 220 Hz, and definitely notice the bass performance and sound staging suffer when crossed over too high.  

     My Magnepan 2.7QR panels are rated as producing bass down to 34 Hz +/- 3 dB.  I think that's fairly accurate but have never measured them.  
     In my room, I've found a low low-pass filter setting works best and  I normally have it set at 40 Hz.  I realize theoretically that leaves an overlap between 34 and 40 Hz , since I run my panels full range, but it still sounds best to me.  
     All 4 subs are run as mono and none have their phase reversed; the Debra manual suggests reversing the polarity on 1 of the 4 subs progressively to verify the bass doesn't sound best in your room with the phase reversed on 1 of the subs.  My setup sounded so amazingly good with all in-phase that I never even bothered with trying this.
     I have absolutely no connection with Audio Kinesis but can honestly tell you that 'm thrilled with how well these dba systems actually provide true sota bass at a reasonable price. 
     You're probably thinking this dba solution sounds too good to be true.  I completely understand this reaction since I was so skeptical when it was originally described to me that I almost didn't buy it.  Thinking back to that time, it's a bit disconcerting how close I came to taking a pass on the Debra, due to cost and space concerns, and how fortunate I now feel that I decided to buy it.  
     It honestly works so well in my room and system that I can't think of any bass quality needing improvement.  I do believe 4 Vandersteen  Sub 9s would provide more bass than the Debra system but I'd really need to compare them to determine which produced better bass in my room. 
    Dbas are ideal bass systems for seamlessly integrating sota bass with any speakers, especially 'fast' panels.  I don't think I'm ever going to need another bass system, even if I switch my main speakers in the future.
Tim

ctsooner,
     My first decent system was a pair of unfinished Klipsch Heresey and a Yamaha CR series 40 watt receiver and modest TT setup that I used through college.  I always regret not trying tubes with that setup but, if I recall correctly, I enjoyed Talking Heads, Peter Gabriel and Supertramp tunes back then at high volumes with some solid punch in the bass.

  " reat bass is amazing, so is state of the art imaging !
a 40 HZ filter is certainly low....not a ton of music down there...
what are you listening to with content down that low ?"

tomic601,
     
   Yes, a 40 Hz low-pass cutoff is fairly low.  My system is a combo ht and music system in my living room.  For ht, I'm getting a lot of content that's 40 Hz and below  both through Bluray discs played//Dolby Digital surround decoded  through my Oppo 105 and even surprisingly high quality content from the local Xfinity  hi-def cable . 
      I'm currently watching an Epix HDTV series  called Get Shorty.  The 24 bit/96 Khz PWM soundtrack is very good, often with a very realistic drum riff in the background.  The drum kit seems to be in the room front and center.  I believe it sounds so realistic because the AK Debra dba system's bass is so accurate, dynamic and articulate/defined; providing natural and life-like bass which makes it very easy to distinguish the heard and felt bass of the kick drum from the sharp and taut bass of the tom-tom.  I also believe there are higher frequency bass harmonics being reproduced by my main speakers, Magnepan panels running full range, that contribute to the very realistic sound stage illusion.
     For music, I don't listen to pipe-organs but my music collection, consisting of ripped Redbook 16 bit//44 Khz CDs and 24 bit/96 Khz hi-res  WAV files on a NAS 10 TB hard drive, must contain deep bass information because I'm hearing the Debra's deep bass contributions consistently. on my music: Fat boy Slim, Parov Stelar, Jennifer Gomes and various Rock/R&B/Blues/Jazz all on CD and hi-res.

Tim 

" @noble100 and others interested in room acoustics: which other fora are you active in?

I'm interested in discussing and posting some measurements (which Agon doesn't allow) and would live to engage others who share that interest.

Cheers!"

Hello lewinskih01,

     Sorry for the delayed response, I just noticed your question today.
   
     First, by your 'Cheers!' sign-off, I inferred that you're an English brother. 
     Unfortunately, it appears we Americans often prefer the siimplest form of things both grammatically and presidentially. We typically employ 'forums' as the plural of 'forum' and only employ the original Latin 'fora' as the plural form when  we're referring to  the marketplaces or public places of an ancient  Roman city forming the center of judicial and public business.
     I realize there are other variances between English and American grammar.  For example, the majority of Americans describe our current president as an 'idiot' or 'dope' depending on region, while the majority of Englishmen likely describe him as a 'wanker'.
 To answer your question, however, I mainly participate on this forum for audio discussions but would recommend other forums, such as Audio Circle and DIY Audio, for subjects such as room acoustics discussed in more detail and scientifically. I participated and learned a lot about class D amps and in-room bass response on those fora. Doing a Google search on "room acoustics" would also prove useful.

Cheers!
 Tim