Audio Kinesis Swarm Subwoofer Awarded 2019 Golden Ear Award by Robert E. Greene

I actually did hang out up in those areas . The oven is a built in double wall oven which is more structural than shelf actually . I shifted the sub into the corner and was up and down the ladder a dozen times setting adjustments while switching from misic to 

Hello davekayc,

     Congratulations, it seems like you happened into discovering a good combination of positions for both of your JBL subs that's providing the very good bass response a dual sub bass system is capable of.  I believe the sub unusually positioned on a shelf over your oven, about 7' above the floor, may be the key to your good fortune.
     The main goal in a dual sub bass setup is to position both subs sequentially in your room at the optimum positions in relation to your listening seat.  The best method I'm aware of for accomplishing this is the crawl method.  If you were starting from scratch, this is the procedure I'd have suggested you follow for optimally positioning each of your JBL subs:

 1. Connect sub#1, place it at your listening seat and play some music with good and repetitive bass. 
2. Beginning at the front right corner of your room, begin slowly walking or crawling around the perimeter of your room, in a counter-clockwise direction, until the bass sounds best to you (smooth, fast, detailed, solid and natural).  Once you find this first exact spot, you move sub#1 to this spot. 
3. Connect sub#2 and place it at your listening seat position, replay the music with both sub#1 and #2 playing and, beginning at sub#1, slowly continue walking or crawling around the perimeter of your room until you discover the next exact spot in your room the bass sounds best to you. Once you find this first exact spot,  move sub#2 to this spot. 

4. Sit at your listening position, replay the music with both sub#1 & #2 playing and verify the bass sounds very good to you.  If it does, your subs are likely optimally positioned and you can continue on to the next procedure phase of optimally setting each sub's Volume, Crossover Frequency and Phase controls.  (Procedure for this phase will be described later.)  If the bass does not sound very good to you at your listening position, you'll need to repeat the procedure starting at step 1.

     The above is the procedure I'd recommend, however, it seems like you just experimented with positioning your subs without following this procedure.  You may have just placed each sub at a convenient or available room position but it's very fortunate that you did, since you apparently discovered an unusual position (7' above the floor on a shelf above your oven) that surprisingly works very well in your room.  The truth is that you would not have discovered this very good but unusual location for 1 of your subs if you strictly followed my suggested crawl method.  You got very lucky because this is a very valuable discovery.
     If you're completely satisfied with the bass response performance of your system from your listening position with your 2 subs in their current positions, I would definitely suggest you leave them right there and buy some lottery tickets immediately.
     If you're not completely satisfied for any reason but you're okay with one sub being located on the shelf above your oven, my suggestion is to just treat the sub on the shelf as an optimally positioned sub#1.  You'd then have the option of further experimenting by treating the sub behind your bar area as sub#2. You could then follow my procedure starting at step#3.  Just place sub#2 at your listening position with both sub#1 & #2 playing and walk slowly around the perimeter of your room and find an exact spot where the overall bass sounds the best to you.  This spot may be behind your bar area or the bass may even sound better, from your listening position, with sub#2 located at a different position in your room.  Only a bit of experimenting and listening from your listening position will let you know for sure.
     I hope this was all clear to you and helped a bit.   


    
     


     
      

I am kn the experimentation phase . I think i have nailed it . Partially of intuition and partly convenience. I happened to have a couple like new powered subs .jbl sp 150 .  Very versatile and adjustable . I went to the music store and bought the best mic cables they had. 100’ plugged into the back of my mac c46 from the balanced output 2 . Main 18” come off of output 1 . 
I found i barely had to have the subs on at all (the powered 10”). I was able to tweek my dual 18” up a bit . For some reason the new setup allowed it.  One sub is up 7’ on a heavy duty shelf above my oven in the kitchen laying on its side on a piece of foam woofer to the wall. In the other corner on the floor the second 10” on the floor on foam ,woofer to the wall behind a large oak bar area . Polarity reversed . Volume as low as possible without the sub thinking its of . I felt the cone and turned the dial until i could sense vibration in my hand . That is all . Now the airspace is so smooth its almost like you are wearing headphones but the stage is in front of you . Pretty cool i already had everything and never considered it before . 

sawdustguy:
"Hello,
I'm curious about the swarm systems and have a couple questions. First, what is the "crawl" process you mention? Second, what do you use for speaker wire? I would need a lot of it as my room is roughly 17' x 27' x 9'. "

     I ordered the Audio Kinesis Debra system from James Romeyn Music an Audio in Utah:  
www.jamesromeyn.com/

     This is basically the same as the Swarm system except the 4 subs are a bit narrower (1'x1'x28").  
The subs are wired to the supplied 1,000 watt class AB amp in series/parallel, with 2 subs connected to the amp's "A" speaker terminals and 2 subs are connected to the amp's "B" terminals.  As an overview, there will be one single-conductor wire run from the amp to each sub and one separate single-conductor wire run between each pair of subs.  All subs operate in mono mode and are fairly simple to connect.  James custom made all of the fairly low gauge and single conductor speaker cable runs required to connect all 4 of my subs at a very reasonable cost.  You'll just need to answer some questions, mainly about room dimensions and cable routing paths, and James will supply you with all the sub cables and written procedures.  You'll just need to do a little wire cutting/shortening and stripping of some of the cables.  My room is 23' x16' x 8' and I was able to run all my cables through the crawl space below

     You can google the crawl method for details but it's basically a simple and free method to optimally position each of the 4 subs sequentially that works extremely well in virtually any system and room. 
     You would begin by hooking up sub#1, place it at your listening seat and play some music with good and repetitive bass. Beginning at the front right corner of your room, you begin slowly walking or crawling around the perimeter of your room, in a counter-clockwise direction,  until the bass sounds best to you (smooth, fast, detailed, solid and natural).   Once you find this first exact spot, you move sub#1 to this spot. 
     You would then connect sub#2 and place it at your listening seat position, replay the music with both sub#1 and #2 playing and, beginning at sub#1, slowly continue walking or crawling around the perimeter of your room until you discover the next exact spot in your room the bass sounds best to you. Once you find this first exact spot, you move sub#2 to this spot.  Complete the optimum sub positioning procedure by repeating this process for sub#3 and #4.  If you have room correction, you can utilize it at this stage if you'd like but it's not actually necessary.
     The final steps required are to optimally set the Volume, Crossover Frequency and Phase controls on the supplied amp/controller.  These settings are just as important as proper sub positioning in achieving best results.  I suggest recruiting a competent assistant and taking your time to reduce setup/configuration time and increase accuracy.







   
     

hleeid:"Would it make sense to experiment positioning the subs on the floor to face the floor (on tall spikes) instead of facing the wall?"

Hello Hans,

Yes, because you’re venturing into new 4-sub DBA territory that I’ve never been to or even contemplated. I’m willing to help you as much as I’m able along the way but my current advise is it’s likely best you experiment with the positioning and facing direction of all 4 subs until you perceive the bass as being smooth, fast, powerful, highly dynamic, detailed and natural. IOW, until it sounds the best to you.
As millercarbon mentioned, just having four well dispersed subs launching bass soundwaves into your room is likely to result in very good bass performance in your room. Your main goal will be experimenting in positioning and facing, analyzing the bass results and then repeating until you determine the optimum, or at least a very good, combination of position and facing for each sub in your room.
The good news is the subs are not very heavy. The bad news is there are a high number of combinations of sub position/facing possibilities in total. However, I’m very confident you’ll consider it well worth the effort once you hear and feel the bass results of even a good, but perhaps not the optimum, combination of sub position and facing for all four subs.
My advice is to recruit or hire an assistant as the muscle and restrict your responsibilities to directing, analyzing the bass performance of each 4-sub position/facing combination permutation and recording the results.

Have fun,
  Tim

@millercarbon 

Yes, I feel I have a basic understanding of the reasons behind the advantages of the Swarm/DBA concept.

Landing right into the "fine tuning" stage makes sense now.

So after everything is set up, I look forward to some listening comparisons:
   
1) Swarm off
  
2) Swarm on but with just one sub (one of the subs under the main speakers) powered on to simulate a traditional single sub setup.

3) Swarm on (all subs on)


@noble100 
 
Really appreciate you taking the time coming up with the experiments! 

I plan to install shelves long enough to span each wall (left, right and rear) but with a 2' clearance from each adjacent wall.
That should accommodate all 4 experiments. 

Would it make sense to experiment positioning the subs on the floor to face the floor (on tall spikes) instead of facing the wall?


Thanks,
Hans 

 

Honestly Hans the advantages of four are so great you can put them just about anywhere and still get great bass. I've moved mine around, played with phase and impedance (wiring for 4, 8 and 16 ohms) and a bunch of stuff and yes it does matter. But compared to how big a change you get moving one sub around the difference when moving one of four is small. It will help to keep this in ind because compared to the major errors just one sub always has when you go to four it puts you right from the beginning into fine-tuning. In other words prepare to be amazed and understand why those of us with four (or more) are such enthusiastic DBA proponents.

Hello Hans,

     Okay, my next experiments were going to be:

Experiment#2: Same as Exp#1 but face the drivers toward the wall instead of the ceiling. Deep bass sound waves are very long (a 20 Hz soundwave is about 56 feet long) and will continue reflecting off of room boundaries (walls, ceilings and floors) until they run out of energy.                 Whether these soundwaves are initially launched upward toward the ceiling, or sideways into a wall, causes their pathways to differ before reaching your ears located at your desk chair.  You'll need to determine if sub positioning and driver facing direction results in the bass sounding different to you and which you prefer.

Experiment#3:  Place a shelf/sub along each right & left side of your rear wall, with the closest edge of each shelf 2' away from the nearest rear corner of the room and with the sub drivers facing the ceiling.

Experimet#4: Same as Exp#3 but face the drivers toward the rear wall instead of the ceiling.

     It's important for you to understand that positioning a sub in a corner will increase that sub's perceived amount of bass produced because the presence of two walls in such close proximity reinforces the reflection of the long bass soundwaves it launches that radiate in a 360 degree pattern. 
     I understood this and specifically avoided corner placement of my four subs, keeping them at least 2' away from any nearby corner, because my goal was the smoothest, most natural and highest quality bass attainable without bass overemphasis.  
     However, your goals may differ from mine and you can experiment with placing at least one sub in a corner with any of your configuration scenarios.  If you do so, I know Duke recommends reversing the polarity on at least one sub that's not positioned in a corner.  
     I hope this info helped a bit.  Lots to learn but your experience gained from experimenting will probably be the best teacher.  

Best wishes,
    Tim

Thanks Tim!  
No need to rush on Experiment#2.  Duke told me he needs about 8 weeks ordering cabinets, amp and build time.

I will probably end up placing shelves along each right and left sidewall as you mentioned in step A.  
Probably will place a shelf on the back wall while i'm at it.(If I am going to drag out tools, measure and mark, drill, etc anyway)

With the floor subs under the mains, and one ceiling facing sub in a corner, that leaves just one sub to experiment with.

Unless I'm missing something, ...

@Duke - Do you place the subs directly under the main speakers?
If so, facing which way?

Thanks,
Hans

hleeid:"@noble100  - Your guess is accurate regarding my room/listening position. Still trying to figure the shelf situation for experimenting.
I know it will be worth the effort though."

Hello Hans,

     Okay, I think I can help with the shelf/sub experimenting locations.  Here's what I suggest for experimenting for best locations for your rear pair of subs/shelf locations in likelihood of success order (according to my somewhat inexperienced opinion):


Experiment#1:  
A.  Place a shelf/sub along each right & left sidewall, with the closest edge of each shelf 2' away from the nearest rear corner of the room.
B.  Determine the exact distance the top of each shelf needs to be from the ceiling allowing for a sub laying on the shelf with the driver facing the ceiling and about 2" away from it. 
C.  Mount the shelves and place a sub with the driver facing the ceiling on each shelf.
D.  When completed, hook up all 4 subs to the amp, set the Volume control on the amp at halfway (12:00), set the Crossover Frequency to approximately the lowest rated output of your main speakers and set the Phase Control at "0". Note: you will fine tune all 3 of these settings for optimum performance once you determine which exact sub positioning you most prefer.
E.  Play some music with good and repetitive bass while sitting at your desk chair and then walk all around your room analyzing the quality of the bass.  Write down your impressions of the bass under the heading of "Notes on Experiment#1 Bass Response"  with separate notes for "Seated at Desk" and "Room in General".

     I'll continue listing more experiments starting with Experiment#2 tomorrow evening.  I've got a meeting from 10am to 1pm tomorrow so I need to get some sleep now.  I hope this helps.  Hopefully, Duke will chime in as you experiment, too.

     Has the complete Swarm kit been delivered?  If not, when is it expected?


Thanks,
 Tim

Hello,
I'm curious about the swarm systems and have a couple questions. First, what is the "crawl" process you mention? Second, what do you use for speaker wire? I would need a lot of it as my room is roughly 17' x 27' x 9'. 

" If I understand correctly, one of the ceiling subs can be in a corner with polarity reversed. " 

I normally suggest one sub in a corner (but no more than one), and that a different sub be the one with its polarity reversed... but, once your check clears, you can try whatever you want! I think it is possible that, in a small room, reversing the polarity of the one in the corner could work well.

Duke

@noble100  - Your guess is accurate regarding my room/listening position.  Still trying to figure the shelf situation for experimenting.
I know it will be worth the effort though.

@davekayc - Duke told me that the ceiling aimed subs should be placed high on the wall a few inches from the ceiling opposite from the wall where the floor subs sit under the main speakers.

If I understand correctly, one of the ceiling subs can be in a corner with polarity reversed. 

@Duke - please correct me if I have it wrong.

Thanks,
Hans

davekayc,

   Refer to my last post from earlier today.


Tim

Hleeid : 
you say two subs under and then two aiming at the ceiling . Where on the ceiling . Above the speakers ? At the back corners ? Please advise .

Hello Hans,

     I wish I could help you more but I have no experience or knowledge about positioning them anywhere but on the floor.  

     I remember your room is a rather small office. I'm picturing your room with your chair backing to the middle of one wall on one side of your room with your desk right in front of your chair.  I'm guessing your speakers are along the opposite wall you're facing when seated at your desk chair.  
    If this is close to true, I'd suggest placing one sub under each speaker along the front wall (the one you're facing from behind your desk). Then locate the other 2 face up toward the ceiling above your desk near the corners (about 2' away from the corner). I'd suggest along the right and left side walls would probably work best. If not, along the wall behind your chair might also work well.
     I believe the import point is to have them positioned well dispersed and not too close to each other.  Please fell free to reach out to me as much as you'd like.  I'm retired, usually have the time and sincerely want to help you as much as I can.  I just wish I had more knowledge and experience positioning them off the floor optimally.  Unfortunately, you may need to do some experimentation to get it right but you should definitely and clearly notice when you do. 
     I know it's difficult placing temporary shelves to even experiment but I don't know of an alternative method. I'll try and assist you as much as I'm able to.

Tim

You can debate the merits of The Swarm concept, or you can just come to Room Monroe at this weekend's Capital Audiofest in Rockville MD (just outside Washington DC) and hear it for yourself.  Gingko Audio Sextet is a collaboration project between AudioKinesis and Gingko Audio, with customs cabinets made by Salk. We will show you how you can grow from a pair of two-way monitors to a 6-piece system by adding up to four subs strategically to a full-range system.You can debate until the cows come home but hearing is believingVinh VuGingko Audio

Hi Tim,

Yes, I just couldn’t figure a way to situate 4 subs on the floor in my small office. So I didn’t place the order.

Then I saw the thread where Duke mentioned positioning subs up near the ceiling.

I spoke with Duke for a while about this. He explained, among other things (wow you can get a college education on one phone call with Duke!!) that this would help with distribution in the vertical plane. Still tripping up on the terminology/jargon but beginning to understand more.

We also talked about placing one sub under each of the main speakers and the other two facing up near the ceiling.

Even better!

This way, with two subs up high, the ones on the floor will not take up any additional space since the main speakers will be over them anyway.

I then placed an order for the Swarm in black finish.

Will probably reach out to you when they arrive for set up advice.

Hans

Hello Hans,

     I remember we previously discussed the Swarm system in another post.
    What's the reason for wanting the subs positioned up near the ceiling?  Are you unable to locate the 4 subs on the floor facing the nearest wall around the perimeter walls of your room?   


Thanks,
  Tim

Congratulations to Duke for well-deserved praise!

IMO the Swarm is one of the best sub systems out there

Thanks Tim!

After speaking with Duke, looks like the crawling will be limited to perhaps just one sub. The other three subs will be positioned up facing the ceiling.

Is there a "crawl" or other method for adjusting the subs up near the ceiling?

I also spoke with Duke about positioning 2 subs directly beneath my main speakers and 2 subs up near the ceiling.

The subs near the ceiling would be more difficult to experiment with placement (unless I install temporary long shelves high up on two walls).

@Any Swarm/DEBRA owners out there - Have any of you placed subs up near the ceiling?


Thanks,
Hans

hleeid:
"Looking forward to crawling around the room setting up the system!"


Hello hleeid,

     Congratulations to you, too!  I'm serious, prepare to be amazed. 
 
     I swear I'm not an AK salesman, just a huge fan of the concept and Swarm and Debra systems.  As I stated, I prefer and used the crawl method to position my four subs sequentially in relation to my listening position with excellent results; the bass performance resulted in being near state of the art bass throughout my entire 23' x14' room including all five other listening seats in the room.
     I used no room correction or bass room treatments but you're, of course, free to use them or other equipment to position the subs or just to verify the results of the crawl method.

Enjoy,
  Tim

I also just placed an order with Duke.

@noble100 - Thanks for being a staunch advocate for the DBA concept!
I learned quite a bit from your postings!

@millercarbon - Thanks also to you for your timely explanations!

Thanks to everyone else who responded to my initial thread: " Searching for matching(?) Subwoofer solution
"

Looking forward to crawling around the room setting up the system!

Hello benzman,

    Congratulations, Prepare to be amazed!  

    Imho, the beauty of the distributed bass array (DBA) concept and system is that it provides near state of the art bass performance in virtually any room and with any pair of main speakers. My advice is just to take your time and strictly follow the sequential procedure for optimally positioning each of the four subs in your room. Any furniture/décor adjustments and cabling concealment can be concentrated on afterwards.
    When I purchased my AK Debra DBA and knew all four subs would be operating in mono, I was a bit concerned about how this would effect my already very good soundstage imaging. I was very pleased and relieved to discover that the addition of high quality deep bass, even though it was in mono, not only significantly expanded the size of my system's soundstage image it also greatly improved the perceived level of detail and realism within the soundstage, including a greater sense of the acoustics of the recording venue.  


Enjoy,
  Tim

I sent my deposit into Duke last week

This system is going to absolutely kick ass in a Golden ratio room with an Iso wall system ! !

Hans asked:  "What are some ways you can suggest to position (suspend/hang?) the subs near the ceiling?" 

Thus far, to the best of my knowledge, all of the Swarm units that have ended up near the ceiling have been placed on the top of bookshelves or something similar.   I don't have any ideas for how to suspend subs from the ceiling... no GOOD ones, at least! 

Audiomaze wrote:  "Can this work with passive subs and a powerful amp driving them in series." 

Yes.  I use series-parallel connections for the four 4-ohm subs to present the amp with a 4 ohm load.  

Duke

     Just wanted to add my hearty congratulations to Duke Lejeune and James Romeyn at Audio Kinesis.
     I purchased the Audio Kinesis Debra 4-sub distributed bass system (very similar to the AK Swarm system, using the same amp and 10" long-throw aluminum woofers, but with sub enclosures that are built locally in Utah and slightly different in shape and size than the Swarm's custom enclosures built locally in Austin, Tx.).  
     I bought mine new about 5 years ago for about $3K and I don't believe I can overstate how well this distributed bass array (DBA) concept and system has performed in my 16'x23'x8' room.  I still use the same Magnepan 2.7QR 3-way main speakers that are 6'x2'x2" dipole planar-magnetic panels that have a rated bass extension of 35 Hz.  
     I drive them with a pair of D-Sonic M3-600-M monoblocks rated at 1,200 watts into the 2.7's relatively stable 4 ohm impedance load.  On their own this resulted in very high quality, well integrated bass from the 2.7s but I was wanting more powerful and dynamic bass that could extend a bit deeper and be felt as well as heard.  
     I have a combination system that I use for 2-ch music and 5.1 surround HT.  I initially added a single older 15" M&K sub and later added a 12" Klipsch sub.  While these subs added more bass, I didn't consider it high quality bass because it was a bit lagging, slow, not very detailed and it wasn't well integrated with my main speakers, sounding somewhat disconnected.
     I was almost ready to give up on subs when Duke's AK associate, James Romeyn. convinced me to buy and try the Debra DBA system on a free 28-day home trial period. 
     It took me most of a Saturday for a buddy and I to properly position all 4 subs, route and hide the wiring in the crawl space below my living room and optimally adjust the volume, xover frequency and phase controls on the amp/controller.
     I can honestly state that the bass quality produced by the Debra 4-sub DBA system in my system and room has been nothing short of a revelation.  I consider the bass as very close to state of the art on both music and HT.  The bass is fast, detailed, smooth, powerful, dynamic and it seamlessly integrates  with the fast, smooth and detailed full-range sound quality of my main speakers.  
     Everything sounds like a well integrated complete whole with excellent bass response just naturally being added to the seemingly expanded and even more realistic soundstage; the bass sounds like it's originating from the proper instruments and voices within the soundstage.  This adds to the perception, on good recordings, of listening to music when listened to live and in person, with bass that is felt as well as heard and with the powerful and wide dynamics live instruments and voices are capable of.
     I believe the bass power, dynamics, speed, smoothness and overall bass quality produced by the Swarm, Debra or even a custom 4-sub DBA system are so good that they will seamlessly integrate with virtually any pair of main speakers and in any room.  
     Congratulations again on your extremely well deserved awards, Duke and James. I highly recommend the 4-sub DBA concept and system to anyone wanting sota bass response in their systems and rooms.  Since these systems will work seamlessly with any main speakers, you'll never need to buy another sub system again, even if you switch main speakers or use very fast planar-magnetic or electrostatic main speakers.  
     I've stated this many times before but it's the honest truth; I'm constantly surprised that more individuals don't know about how effective DBAs are and that more don't use one, especially members of a high quality audio site.

Tim
  
  
 
 
 
 
     
     

Can this work with passive subs and a powerful amp driving them in series. 

Avanti1960 wrote:

"I have successfully integrated one and two subwoofer solutions into my system when the main speakers had a natural roll off (acoustic crossover) that made for a near ideal low pass frequency relative to the subwoofers. However I was not so successful with a recent set of main speakers that had extended low frequency output to 20Hz from the transmission line port."

I’m not aware of anyone using a Swarm with main speakers that go down to 20 Hz. Overlapping that much with the mains wasn’t part of my game plan. What be inclined to I’d try is, reducing the output from the transmission line terminus (probably with open-cell foam) so that the subs can be turned up louder without making the low end too thick.

"I am now on a new set of main speakers and although I love the bass, measurements show that it reaches a certain output and levels off while the rest of the frequency spectrum can get louder. I miss the louder bass with more impact as the volume increases."

I’m not clear about what the issue is. Is the bass region compressing? Can you describe in more detail what the measurements show?

"Would the 4 sub array lend itself to better integration with main speakers that are near full range (avoiding bass quality and blurred midrange issues) without high passing them?"

So far we’ve been able to integrate well with unfiltered main speakers that go down as low as 30 Hz. Sometimes with overlap, sometimes not. Sometimes using the single band of parametric EQ and/or the phase control to reduce the amount of reinforcement in the region of overlap. "Blurred midrange" makes me think the subs were being rolled off too high and/or too shallow, and may have been too loud.

"In my two-sub setups I found that I needed to adjust the phase of each individually for best integration. Why wouldn’t I need to do this with the swarm system? "

I’m not an expert on optimizing two-sub setups, so I can’t thoroughly compare and contrast. But in general we want the in-room bass energy de-correlated for best results, and that includes for blending with the mains. You were introducing some de-correlation by having two subs instead of one, and some more via the different phase settings. The Swarm introduces a lot of decorrelation via the widely-spaced asymmetrical placement and reversing the polarity of one of the subs. Some Swarm systems use two amps, usually set 90 degees apart in phase.

I haven’t had anyone yet tell me that they can’t get a good blend between the Swarm and their mains, whether they are using one amp or two. I think the decorrelation that a distributed multi-sub system brings to the table help make that blend less problematic to achieve.

But you can certainly use multiple powered subs of your choosing and thereby be able to adjust phase and frequency and gain of each independently.

Duke

Congrats on the award and the idea of applying sound theories and principals that resulted in a product that stretches the envelope of home audio performance.  
I have successfully integrated one and two subwoofer solutions into my system when the main speakers had a natural roll off (acoustic crossover)  that made for a near ideal low pass frequency relative to the subwoofers.  
However I was not so successful with a recent set of main speakers that had extended low frequency output to 20Hz from the transmission line port.  I used two high quality highly adjustable subs (via a remote app) and although 80% of music sounded great, the other 20% caused issues that I could not live with- blurring midrange and low quality bass definition being the most common.  
I probably would have had better luck if I filtered the main speakers but this is something I am not willing to do because of practical implications and personal preference / audio sensibilities.    
I am now on a new set of main speakers and although I love the bass, measurements show that it reaches a certain output and levels off while the rest of the frequency spectrum can get louder. 
I miss the louder bass with more impact as the volume increases.    
One option I have is to increase amplifier power.   This should work well.
Another option I have is to try again with subwoofers (which I am reluctant to do) 

Would the 4 sub array lend itself to better integration with main speakers that are near full range (avoiding bass quality and blurred midrange issues) without high passing them?   How?  

In my two-sub setups I found that I needed to adjust the phase or each individually for best integration.  
Why wouldn't I need to do this with the swarm system?  

Thanks.  

Congratulations Duke! 

I'm in the process of building a swarm of Dukes design using 4 12" drivers called the Duke 24.  Made by Leland at Speaker Hardware, the cabinets are built and exterior is waiting for me to apply veneer.  I am using the dayton audio sa1000 to drive them.

Mike 

Duke,

I have 4 different systems set up throughout my house.  My main system has 4 subs in it (plus a HSU mid-bass module I engage for movies).  The other systems all have one sealed sub each.  I'm in a good situation where my girlfriend and I both have our own places and when she comes over she loves to listen to music with me, so I get zero push back on how many subs or records or turntables or whatever I have.  Life is good.

That may be a very good subwoofer but not only for the money must being a great subwoofer period ,and have one subwoofer of the year ,and by far most technically advanced, and controlled on their app. The SVS 
SB- 3000,13 inch driver, for under $1k delivered 
60 day money back guarantee they will even pay the shipping both ways   A scaled down version of the great flagship ultra 16
it has a 800 wpc high current Bash amplifier ,2600 watt peaks , goes 
down to 28 hz, 50 MHz-56 bit Processor for precision control 
and a split coil voice coil ,which is this and their flagship the only ones out there ,meaning great Bass even at lower volumes using the inner part of the coil.when things get demanding then it uses the bigger outer part of the coil 
for this price and a discount if you buy2 for $1900 two great subs to balance your room out . Just check out the reviews .i have had Rel, JL Audio and even at $2k
no sub better  check it out at see allthe rave reviews ,and No one 
offers a 5 year warranty, and 60 day audition ,they also have a ported version which gives more impact for movies. But for music sealed is better and 54 lbs,only 15 inch square.

Rooze wrote: 

" I can’t get beyond the notion that some subs just don’t sound very good, and multiplying an average sounding sub by four surely doesn’t equate to good quality bass.... how can it?" 

I think the suitability of the subs for this application matters. Back to that in a moment.

The biggest issue at low frequencies is room interaction. Compared to the few dB difference between good subs, the peak-and-dip patterns that rooms impose on subs are huge. By spreading multiple subs around the room, we get four significantly different room-interaction peak-and-dip patterns. The more different peak-and-dip patterns we are summing, the smoother the net result.

Now ime subs with huge bottom ends are generally not the best choice for a distributed multi-sub setup. My understanding is that your Hsu’s have pluggable ports, and ime that can be very helpful in getting the in-room bottom end balanced right (it’s what I do too). If you had four Hsu’s with pluggable ports, I’d say start out with the ports plugged in all of the subs except for one, the one nearest a corner. One sub in one corner is okay, but I suggest no more than one. If the Hsu’s have phase adjustment, put the one farthest from the main speakers in reverse polarity, unless that’s the one with the ports open.

Then if you need more low end, unplug one port (your choice which one). If you need less low end, plug ports in that sub nearest a corner. I have zero experience with a quartet of Hsu’s, but this is what I would try. The ability to plug ports in the Hsu’s may make them actually more suitable fort this application than most subs.   I'm not suggesting you buy two more Hsu's - just tossing out an idea of how Hsu's might be used. 

Duke

Duke, Congrats on the well deserved recognition! We spoke last spring
about getting the Swarm into the mix for our Speakerfest Event.
This year's event will be Stand mount speakers only.

What a perfect way to show off the Swarm! Surrounded by the likes
of Vimberg, Dali, Borreson, Joseph, ATC, Harbeth your product
will be a perfect match. We may even sell a few sets!!

Best,

Jeff Kalina, AZAVClub.com

Duke - your honesty and transparency laudable- thanks for putting together a turnkey system, and at an affordable retail price.

Congratulations Duke!!
Even a newbie like me can understand how well deserved this award is (not to mention how overlooked and underappreciated your design is)!

@Duke - you mentioned that:
What would be really sweet is, three subs near the ceiling and the fourth one closer to the floor

This looks like a deal maker for me since my room is very small.
What are some ways you can suggest to position (suspend/hang?) the subs near the ceiling?

Thanks,
Hans

Congrats Duke on additional recognition for your research and efforts and also for selflessly sharing links to DIY products that might compete with your own.

 I’ve been keen to try the swarm arrangement but so far haven’t adventured beyond two subs. My reluctance to invest in more hardware comes from my skepticism, which comes from having read people commenting that pretty much any sub will do, as long as there’s four or more.
I can’t get beyond the notion that some subs just don’t sound very good, and multiplying an average sounding sub by four surely doesn’t equate to good quality bass.... how can it?
Smoother and a more even response maybe, but what about tight, extended and tuneful bass well integrated with the mains? 
I use two HSU subs in my system, both older designs (VTF-1 VTF-2). They’re ok but not great. How can adding two more of the same fix the deficiencies of these mediocre subs.
I’m not trying to pick a fight, I’m just genuinely curious and trying to learn.
 

" If I didn’t already have 8 subs... "

Your eight subs intelligently distributed are probably twice as smooth as my four.

In general, the in-room smoothness goes up, and the spatial variance (variation in frequency response from one location to another) goes down, as the number of intelligently distributed sources increases. So two subs are twice as smooth as one; four subs are twice as smooth as two; and eight subs are grounds for divorce in most jurisdictions.

So I stopped at four.

Duke

Congratulations Duke!  I think it's well deserved, and whether it's "unique" or not, who cares.  You brought something to market that's affordable and from all accounts, works great.  I've yet to hear of one person that said "yeah, I tried it but it didn't work for me".

If I didn't already have 8 subs, I would have certainly considered it for my system.  I have employed the concept in my system, using 4 of the subs I already had throughout my room and to my ears the results are spectacular.  I have a big room with two relatively small Harbeth Super HL5 Plus speakers.  The difference between having the subs on and off is night and day.

If you can achieve similar results for less than half of what all my subs cost (two Rythmik F25s and two SVS SBS13 Ultras), and take up less space, have less controls to fiddle with, that deserves an award (or more).

Congrats definitely deserves it!!!

" Would this work if the speakers weren’t on t floor but up higher say close to the ceiling or in the ceiling facing down?" 

Yes. 

What would be really sweet is, three subs near the ceiling and the fourth one closer to the floor. This would usefully distribute the sources in the vertical dimension, complementing the distribution in the horizontal plane. But if that’s not feasible, four on the ceiling is just as good as four on the floor. 

Also, it is not necessary that all four subs be identical. Earl’s personal first-generation multisub system included a single massive ubersub that went considerably deeper than the other three.

Duke

Would this work if the speakers weren't on t floor but up higher say close to the ceiling or in the ceiling facing down?

Thank you very much, david_ten!!

The Swarm’s first awards were four years ago, in 2015, so I have been fortunate that the concept apparently has a good shelf life. Credit to Earl Geddes, whose idea I’m using (with his permission).

"Again, what about the swarm is unique other than being sold four woofers and told to place them a certain way?"

Totally valid question. As you have figured out, the concept can be implemented in many other ways.

The basic idea is to have a lot of bass sources distributed far apart around the room. Todd Welti and Earl Geddes were the first to advocate this specific approach to the best of my knowledge; Todd investigating symmetrical placement strategies and Earl investigating asymmetrical ones. They developed their ideas at approximately the same time but were unaware of one another’s work.

I don’t think any one feature or characteristic of the Swarm is unique, but I think the combination is probably unique, at least in its general price ballpark:

- The four passive subs are optimized for lower in-room extension than you normally see from 10" subwoofers (20 Hz ballpark), in part because we know in advance that we’ll be using four of them so we don’t need to optimize for max SPL.

- The single shelf-mounted amp that drives the four subs has some nice features, including a 4th order lowpass filter, a single band of parametric EQ, and a continuously-variable 0-180 degree phase control. And since it sits on a shelf, it’s less likely to fail (better cooling and less vibration) and easier to replace if it does. A second amp can be added for some performance improvement.

- The native response curve of the individual subwoofers is the approximate inverse of "typical" room gain. The individual subs have a pluggable port, which can transform them into low Qtc sealed boxes, better suited for small rooms. In my modest-sized living room, the ports are sealed in three out of the four.

- It’s easy to reverse the polarity of one of the subs, which usually improves the in-room smoothness (and smooth bass = fast bass).

- The woofers I use have unusually powerful motors. Their combined motor strength is greater than any single home audio woofer I am aware of (including the discontinued monsters from TC Sounds, Aura, and Acoupower), and to the best of my knowledge surpassed only by the most powerful 21" prosound subwoofers. Not sure "motor strength per dollar" is a thing, but if it were, the Swarm would score pretty high.

- WAF isn’t too bad. With the port and input terminals on the bottom of the box, and the woofer on a side, those sides faces the wall and then the subs just look like four wooden blocks, each with a footprint of one foot square and height a bit less than two feet.

In other words, I didn’t just package four subs together and concoct a marketing scheme. I started with Earl’s concept and made my design choices with a specific end in mind.

That being said, there is nothing about the Swarm that a hard-core DIYer couldn’t equal or surpass. Here is the amp that I use, in case anyone wants to give it a go: https://www.parts-express.com/dayton-audio-sa1000-subwoofer-amplifier-rack-mountable--300-811

Leland Crooks of Speaker Hardware offers 12" passive subwoofer kits that I designed, four of which would outperform the Swarm.

Duke

The fact that you’re getting all worked up about it answers my question.  So basically it’s just a package of four average sub woofers sold as a set with instructions on how to place them.

Cool.  

Well first it was special, now its unique. The award and thread is for recognizing a quality product. I'll post the excerpt since you seem not to have read it:

"redefines the boundaries of the possible in my experience in correct reproduction of bass in small rooms. With suitable recordings, the listening room’s acoustic signature is effectively erased and replaced by that of the recorded acoustics. There is solid theory behind this, but the listening results speak for themselves."

What exactly are you trying to figure out, really?

Again, what about the swarm is unique other than being sold four woofers and told to place them a certain way?  I’m genuinely trying to figure this out.

I have owned and set up multiple stereos with 4, 6, and 8 subs, so this isn’t exactly unfamiliar territory.

Right. Anyone willing to learn can do this with any sub woofers. Anyone willing to learn can also DIY their own, which is what I did. Which, as far as I can tell, almost no one does.

There seems to be hardly anyone who even acknowledges the superiority of the principles on which the Swarm, or distributed bass array, is based. So you take a lot for granted.

But to answer the question, what makes the Swarm so special is there's nothing else on the market quite like it. No other low bass solution comes anywhere close. In fact the only other system that is sold as a system turns out to also be designed by Duke! So yeah, pretty special.

I don't understand -- you can do this with any sub woofers.  What makes the "swarm" so special?