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.
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.
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?
hleeid:"Looking forward to crawling around the room setting up the system!"
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.
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.
Refer to my last post from earlier today.
- 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."
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):
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?
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.
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?"
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.
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.
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'm guessing from your huge room dimensions that you live in a loft. I've learned that getting the bass right in most home rooms is a key factor in building a high quality, realistic home audio system but it's also usually the hardest part of the audio spectrum to get right.
Most people can very quickly tell the difference between music heard in person played live and the same music played back via a recording on a home audio system. I believe bass that is felt as well as heard, detailed, textured, solid, impactful and with a powerful dynamic range, basically bass that has the qualities of bass played live and heard in person, is required to be replicated on a home audio system in order for the experience to be perceived as realistic and of very high quality.
The main reason good bass performance is so difficult to obtain in most domestic rooms is that bass soundwaves behave very differently than midrange and treble soundwaves behave in any given room. Here are some important facts to understand and keep in mind:
1. Humans generally have an audible hearing range from deep tones to high tones of 20 Hz (deepest tone) to 20,000 Hz (highest tone).
2. The deeper the tone, the longer the corresponding soundwave produced. The higher the tone, the shorter the corresponding soundwave produced. For example, the full cycle soundwave length of a very deep 20 Hz tone is 56 feet and the full cycle soundwave length of a very high 20,000 Hz tone is only a fraction of an inch.
It's also been proven that the entire length of a full cycle soundwave must exist in a room before it is detected by our ears, our brains process this information and the perception is created of a sound tone at a certain frequency being present in the room.
3. Most humans cannot localize bass tones below about 80 Hz, meaning we cannot determine exactly where the sound is originating from. But we are progressively better at localizing sound tones as their soundwave frequencies rise from about 80 Hz all the way to about 20,000 Hz.
4. The radiation pattern of deep bass soundwaves is 360 degrees meaning the soundwaves radiate out from the speaker in all directions. The radiation pattern of midrange and treble soundwaves are much more directional meaning the soundwaves radiate outward from the speaker more in a straight line, like a beam of light.
You're on the right track thinking about all the angles of reflections in your room. As you can see from the above fact #2, one of the reasons it's difficult to get good bass performance in domestic sized rooms is that the length of some deep bass tone soundwaves may exceed one or more of the dimensions of the room. This means the long bass soundwaves must reflect off a room barrier (wall, floor or ceiling) before its entire length exists in the room, the ear can then detect it and the brain can process it as a bass tone sound at a certain frequency.
In smaller rooms, multiple long bass soundwaves reflecting off room boundaries, that are closer together, often meet or collide which causes bass at these spots in the room to sound exaggerated, attenuated or even absent. Actually, you're fortunate again because your room is so large it can better accommodate multiple long bass soundwaves, which means fewer reflections off room boundaries that results in better bass response performance overall in your room.
Did you buy those lottery tickets yet?
Are you stating you're using 2 Greg Timbers designed 12 cu.ft. sub cabinets with an18" JBL 2245h driver in each as DIY main subs and you're also using 2 JBL sp-150 subs for a total of 4 subs in your room?
"Most every frequency had a standing wave in a slightly different location from each other . But most landed where i had each of the rear subs. (Rear subs off ) sound right to you tim ? Felt like i should be putting them in the obviously quiet spots . A couple spots would almost cancel out."
Yes, it sounds exactly right to me. The reason there were bass standing waves, and noticeably poor bass performance at the rear of your room, was because you only had the 2 front subs launching bass soundwaves into the room if you turn off the rear 2 subs. But this makes perfect sense to me given my understanding of the 4-sub DBA concept.
It's important to understand that having 4 subs well distributed throughout your room and launching bass soundwaves is the key ingredient of the 4-sub DBA concept and the main reason it works so well in virtually any room. Reaching the threshold of having 4 subs launching bass soundwaves into the room is not an option but a requirement.
The way it really functions is a bit counter-intuitive and involves psychoacoustics. The 4 subs actually significantly increases the number of bass modes ( spots in the room where both directed and reflected bass soundwaves meet at various angles and cause spots of bass exaggeration, attenuation and even cancellation) existing throughout the room. However, our brains process the presence of these numerous bass modes by summing and averaging the bass information by frequency and this rather unexpectedly creates the perception that the bass is very smooth, fast, detailed and natural. This process is referred to as psychoacoustics.
By turning off your 2 rear subs, the overall quantity of bass modes existing in your room is significantly reduced and your brain is only summing and averaging the smaller number of bass modes existing in your room which is not sufficient to create the perception of smooth, fast, detailed and natural bass.
You're stating you mainly detect poor bass performance at the rear of your room with your 2 rear subs turned off. I believe if you made a more thorough sound quality canvassing of your entire room, however, you'd likely detect poor bass performance at other specific spots in your room.
Overall, I think you've done an excellent job of creating a high quality custom 4-sub DBA system in your very large room with seemingly little assistance. Congratulations and enjoy.
I'm achieving the same excellent bass quality and soundstage imaging results you described in my 23' x16' x8' room and have been enjoying it daily on both music and HT. I think it's important that readers of this thread realize that the 4-sub DBA concept is capable of providing these excellent results in virtually any size room.
I feel it's also important for all to know that buying a complete Audio Kinesis Swarm or Debra 4-sub DBA system for $3,000 is convenient but not the only option, custom 4-sub DBA systems can be created using any 4 subs properly positioned and configured. The 4 subs don't even need to be the same brand or model and individuals can buy the same 1K watt Dayton amp from Parts Express (usually for about $300-$500) and build 4 DIY subs if they'd like.
The 4-sub Swarm DBA system requires no equalization, bass room treatments or room correction. Just follow the sequential positioning procedure for each sub, one at a time, until all 4 have been optimally positioned in the room. Once all are positioned, there are controls on the supplied amp/control unit that that are done once and effect all 4 subs equally as a group. The controls on the amp/control unit that need to be optimally set are Volume, Crossover Frequency and Phase. I can explain in detail how best to set these but it’s not relevant right now to answer your question.
Your scenario, attempting to optimally position and configure a 2 sub bass system requires a different procedure. Best practices calls for first using the crawl method (google it) to optimally position each of your independent subs, with independent volume, crossover frequency and phase controls existing on each sub, in relation to your listening seat for each sub sequentially. Here’s a good procedure for you to follow:
1. Set sub#1’s volume control to about 50% (12:00 on the control), the crossover frequency control to the lowest rated bass frequency your main speakers are capable of producing and the phase control to in-phase (’0").
2. Hookup sub#1 and position it at your listening seat location and play some music with good and repetitive bass at a medium volume level.
3. Starting at the front right corner of your room, begin slowly walking or crawling on your hands and knees around the perimeter of your room in a counter-clockwise direction until you find the first exact spot in your room that the bass sounds best to you (solid, smooth, fast, detailed, dynamic and natural). Once you identify this exact spot, reposition sub#1 to this position.
4. Hookup sub#2 and position it at your listening seat location and, with sub#1 playing at its new position, play some music with good and repetitive bass at a medium volume level again.
5. Starting at the new position of sub#1, continue slowly walking or crawling on your hands and knees around the perimeter of your room in a counter-clockwise direction until you find the second exact spot in your room that the bass sounds best to you (solid, smooth, fast, detailed, dynamic and natural). Once you identify this exact spot, reposition sub#2 to this position.
At this point, both subs should be optimally positioned in your room. To verify, sit at your listening position and once again play the music with good and repetitive bass. If the bass sounds very good to you and is very well integrated with your main speakers, then the optimum positioning of both subs in your room has been verified. If not, you’ll need to repeat this procedure starting with step #1.
Once both subs have been verified to be positioned optimally in your room, this very good bass response performance in your room can be even further improved, or fine tuned, by optimally setting the Volume, Crossover Frequency and Phase controls on each of your subs individually.
To perform this bass fine tuning in your room you have 2 options:
Option#1- Do it manually by ear and to your preference by recruiting an assistant; with you sitting at your listening seat and music with good and repetitive bass again playing, the assistant can adjust the 3 available controls (volume, crossover frequency and phase) one control and sub at a time at your direction until you’re completely satisfied with the results.
Option#2- Do it automatically by running the room correction function on your subs one at a time and individually.
For best results, I recommend performing both options and utilizing the resultant control settings that you think performs best. Based on personal experience with different brands of subs than yours, I’m virtually certain each option will result in different combinations of settings and one option will provide clearly superior results.
If you follow my instructions above, I’m very confident you’ll be pleased with the bass performance of your 2-sub bass system in your system and room. You’ll also have the future option of adding 2 more subs of your choice and creating your own custom 4-sub DBA system that would likely equal or even surpass the near state of the art bass performance of the Audio Kinesis Swarm or Debra 4-sub DBA systems.
The only disadvantage of a custom 4-sub DBA is the need to set the 3 crucial sub controls (volume, crossover frequency and phase) individually for each of the 4 subs rather than once for all 4 subs as a group on the Swarm and Debra DBAs.
Hope this helped you,
I was following this thread but it now seems like something mysterious happened to make it somehow be out of sequence and therefore no longer easy to follow.
I posting this on Sunday morning on 10/17/19 just as a test to find out sequentially whether it is placed properly. If it's properly placed as the last and most recent post, perhaps this post can serve as a marker so we can then continue this thread's discussion in a normal subsequent progression, meaning one after the next with the last post being the most recent.
We shall see.
Well, my first test post today, 11/17/19, confirms that Audiogon seems to have a system malfunction that places the most recent post on a thread first sequentially which is the exact opposite of how post sequencing has been handled here previously for years.
Did I miss the notice that Audiogon decided to change the sequencing of posts? If so, somebody made a real bone-head decision that suddenly throws a huge monkey wrench in their forum functionality.
I find it hard to imagine the administrators of this forum would be this dim-witted but I'll need to wait and see.
Thanks for the tip on sorting. Fortunately, it looks like today everything's back in normal order. Maybe it was just an IT issue that they fixed.
I'm glad you got your Coincident sub cabinets working and integrated well with your main speakers.
If you have the time and inclination, I'd suggest that even higher quality bass performance and more seamless integration with your main speakers can be obtained by adding 2 subs to your system. All you'd need to create a custom 4-sub distributed bass array (DBA) system in your room is to use 2 additional subs with 10 or 12" drivers and position each using the crawl method. The main obvious benefits would be greater bass detail, impact and dynamics along with a seamless integration with your main speakers.
The 4-sub DBA concept works incredibly well in virtually any room and with any pair of main speakers. I know you'd be very pleased and amazed if you give it a try.
"The "Earl Geddes" effect done right is just SPOOKY! It takes all of your rooms weakness’s and makes them work against each other push/pull, Yeng Yang, Women are from Venus and Men are from Mars. Good bass is not just about pounding AC/DC although it can do it right. More importantly it will bring your highs, mids, and sound stage depth to a new level. Like plannars Maggies or Soundlab stats done right. It is just hypnotic and SOOOOO much better. Im trying to get that with Kinergetics SW 800s right now and asking for advice. But I will be using 26 10 inch woofers instead of 4. I have heard the Audio Kinnesis system and it is simply amazing. I just happen to like AC/DC and hate my neighbors Haha. "
You’ve experienced the Earl Geddes inspired 4-sub distributed bass array (DBA) concept that Duke Lejeune and James Romeyn of Audio Kinesis have developed into their Swarm and Debra 4-sub DBA complete kit systems. Having used the AK Debra 4-sub DBA system in my system and room for about the last 5 years, I completely agree with your description of the bass performance results as SPOOKY good. I would just add to your colorful description of the way it works to explain my understanding of the degree that adding subs actually increases the bass sound quality in virtually any given room:
To summarize PHD Dr. Earl Geddes’s scientific findings that were later developed into the more practical 4-sub DBA concept and product by others- In virtually any given room, 2 subs will produce bass that sounds about twice as good as 1, 4 subs will produce bass that sounds twice as good as 2 and each sub added beyond 4 will only result in producing bass sound gains that are smaller in magnitude and more marginal. This is the reason the AK Swarm and Debra systems utilize 4 subs.
As far as your requested advice on how to get the same bass quality performance gains that a 4-sub DBA provides by utilizing your Kinergetics SW-800s, some advice I can offer is that there are obstacles you’ll likely face in your endeavor.
You stated that you’ll be using 26 10 inch woofers instead of the Swarm’s typical 4 10 inch woofers, one per sub cabinet. It’s my understanding that the Kinergistics SW 800 are sub towers that each contain 5 10 inch woofers arranged vertically. Does this mean you have 5 SW- 800? If so, this would equal 25 total 10 inch woofers(5subsx5 woofers each=25), Where does the extra 26th 10 inch woofer reside? In a separate cabinet as a discrete additional sub?
I’d like to advise you on how to optimize the bass performance in your room using your SW-800s but I first need your answers to the above questions to do so effectively.
Congrats and welcome to the DBA Concept club! Even in your huge room, I don't think there's a need to go beyond 4 subs but, otoh, 6 subs is...… extremely cool.
Each sub beyond 4 will not only marginally increase the perception of the bass as being smoother, faster, more detailed and natural, it will also increase the overall perceived system bass quantity, impact and bass dynamics.
You are now officially a member of the esteemed 4-sub DBA Concept club. Having automatically earned this coveted honor upon utilizing 4 subs in your room and system, you nevertheless bravely ventured forward into unchartered bass territory, beyond state of the art bass, by continuing to deploy additional subs #5 and 6. That my adventurous and intrepid grasshopper, is definitely worthy of at least another superlative, nice job!
Venture forth and prosper,
Another Swarm bass success story that, as an owner of the AK Debra 4-sub distributed bass array (DBA) system, doesn’t surprise me at all.
I’m glad you posted again, Duke, because I was just going to contact you with a question I have about whether room bass treatments negatively or positively effect the performance of the Swarm/Debra bass systems in a given room.
I recently had a free analysis of my room by GIK Acoustics done and they recommended I utilize some of their bass treatment products in my room, mainly the following:
1. Stacked TriTraps in all 4 corners of my room.https://www.gikacoustics.com/product/gik-acoustics-tri-trap/
2. 244 2’x2’ and 5.25" thick bass trap panels on the floor level of my front 14’ 2" front wall behind my Magnepan 3.7i main speakers. https://www.gikacoustics.com/product/gik-acoustics-244-bass-trap-flexrange-technology/
This plan would result in a 2’x2’ Debra sub being located between a 2’x2’, 5.25" thick 244 bass trap panel and the bottom TriTrap located in the corner behind each main speaker which are both positioned about 3’ away from the front wall.
My question is what effect do you think these combined bass room treatments would have on the overall perceived bass response in my 21’x12.2’x8’ room?
The current bass response with the Debra system operating in my room is extremely good with zero room treatments and room correction in use. My main concerns are doing no harm to the current results and not spending the time and money on these treatments if you don’t believe they’ll have a meaningful positive effect.
Within a few weeks on a different but related concern, I’m also going to upgrade my about 25 year old pair of Magnepan 2.7QR main speakers, containing quasi-ribbon treble sections, with a pre-owned pair of 1 year old Magnepan 3.7i speakers, with true-ribbon treble sections. Given your considerable experience in speaker design, room acoustics and knowledge of Magnepan speakers, I was hoping you could also give me your opinion on my general plan for utilizing GIK room treatment products to optimize the perceived full range frequency response of the pair of 3.7is in my room.
The 3.7is will be positioned about 8’ apart, with the true-ribbons on the inside, along and about 3’ away from the front short wall with my listening seat about 12’ away centered on the rear short wall. There’s a 6’ tall x 8’ long window section along the left 21’ long wall, covered by a plantation blind window treatment with 1" wide wooden horizontal slats, that begins about 2’ in front of the left 3.7i and continues for 8’. The right 3.7i is positioned at the beginning of a 4’ x7’ opening at the front of the right 21’ long wall. The remaining portion of this section is a solid wall with no other openings with an 8’ leather couch positioned along it.
There’s also a wall mounted 65" hdtv centered along the 12’ wall between my speakers and a Magnepan CC3 center ch speaker attached to a smaller tv wall mount that positions it just above and centered on the hdtv beow it.
My general plan is to use an approximate 50/50 balance between absorption and diffusion GIK treatments throughout the entire room with nothing on the 8’ tall ceiling and the floor covered with fairly thick wall to wall carpeting. There are room pics on my profile page if it helps.
As I stated, this plan would result in a 2’x2’ Debra sub being located between a 2’x2’ 244 bass trap panel and the bottom TriTrap located in the corner behind each main speaker which are both positioned about 3’ away from the front wall. There will be side by side 24.5" w x 48.5" tall GIK 242 absorption panels, with diffusing scatter plates underneath the top cloth covers and positioned above each bass trap and sub behind each 3.7i.https://www.gikacoustics.com/product/gik-acoustics-242-acoustic-panel/
The remainder of my plan is to use an even distribution of absorption, diffusion and combination panels on the remaining solid wall portions on both side walls and rear wall. The goal being to ensure that there’s adequate diffusion of soundwaves at the front and rears of the room to avoid over damping the overall room and sound.
Based on your knowledge and experience, do you believe my overall plan is a good one?
I really appreciate any help you can offer, I’d like to order all GIK treatments by end of tomorrow, Thursday Dec. 12th.
audiokinesis:"In my opinion room treatment in the bass region is virtually always beneficial, as the improved damping reduces the magnitude of the peak-and-dip swings."
Thanks Duke. My room acoustics and GIK products efficacy adventures begin.
The bottom octave refers to 16-32 Hz, 32-88 Hz is what is technically referred to as the 'or so'.
Here’s what a wrote on my first post on this thread:
" 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."
I just confirmed the part I stated about " 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 just bought a pre-owned pair of Magnepan 3.7i speakers from a local shop and traded in my almost 25 year old pair of Magnepan 2.7QR speakers that were still going strong and sounding good.
I just had to connect the 3.7is, position them about 8’ apart from each other, with a slight toe-in and the true ribbon tweeter sections on the inside to optimize the mid/treble and dial in the imaging at my listening seat about 12’ away and I was all set.
The only thing I needed to adjust on my Audio Kinesis Debra 4-sub DBA system was to slightly decrease the volume and crossover frequency settings on the supplied sub amp/control unit and the bass seamlessly integrated with the 3.7i just as it did with the 2.7QR.
All 4 subs remain in their exact same positions and there’s still no bass room treatments or room correction software/hardware utilized. I’m fairly certain the AK Swarm or Debra 4-sub DBA systems would still provide excellent in-room bass response and seamless integration regardless of the main speakers I chose and whether or not I changed rooms. Although I do concede I’d likely need to start anew in sequentially positioning each of the 4 subs and setting the control settings to optimize the bass performance if I’d chosen to utilize traditional dynamic main speakers.
Just thought readers would like to know that claims of the 4-sub DBA concept working equally well with any pair of main speakers and in virtually any room are not exaggerations.