Help me understand "the swarm" in the broader audiophile world


I'm still fairly new out here and am curious about this Swarm thing. I've never owned a subwoofer but I find reading about them--placement, room treatments, nodes, the crawl, etc--fascinating. I'm interested in the concept of the Swarm and the DEBRA systems, and I have a very specific question. The few times I've been in high-end, audiophile stores and asked about the concept of the Swarm, I've tended to get some eye-rolling. They're selling single or paired subwoofers that individually often cost more and sometimes much more than a quartet of inexpensive, modest subs. The same thing can be said for many speaker companies that make both speakers and subs; it's not like I see Vandersteen embracing the use of four Sub 3's. 

My question is this: do in fact high-end stores embrace the concept of multiple, inexpensive subs? If not, cynicism aside, why not? Or why doesn't Vandersteen or JL or REL and so on design their own swarm? For those out here who love multiple subs, is it a niche thing? Is it a certain kind of sound that is appealing to certain ears? The true believers proselytize with such zeal that I find it intriguing and even convincing, and yet it's obviously a minority of listeners who do it, even those who have dedicated listening rooms. (I'm talking about the concept of four+ subs, mixed and matched, etc. I know plenty of folks who embrace two subs. And I may be wrong about all my assumptions here--really.)

Now, one favor, respectfully: I understand the concept and don't need to be convinced of why it's great. That's all over literally every post on this forum that mentions the word "sub." I'm really interested in why, as far as I can tell, stores and speaker companies (and maybe most audiophile review sites?) mostly don't go for it--and why, for that matter, many audiophiles don't either (putting aside the obvious reason of room limits). Other than room limitations, why would anyone buy a single JL or REL or Vandy sub when you could spend less and get ... the swarm? 


northman
unreceivedogma:
" A friend of mine who was the audio guy for the Untied Nations and the DJ for the Nuyorican Poets Cafe gave me a tip, which I have to try over the weekend:

Put the sub in the spot where your listening chair is. Then walk around the room. When you find the spot where the bass sounds tightest and deepest, that’s the spot to place the sub.

Assuming this theory works, I’m hoping that spot isn’t in front of the door to the room."

Hello unreceivedogma,

     Your friend's tip is a good one that I've used and recommended many times with very good success.  It's commonly referred to as the 'sub crawl' method and you're highly likely to find it to be very effective in your room as well.  
     If the result is actually in front of a door, placement immediately to the left or right side of the door will probably also result in very good bass perception at your listening seat.  This is technically a bit of a bass performance compromise but you can decide for yourself if it's a sufficiently subtle one to be acceptable. 

Tim
Right. If we are talking about a 2 channel high fidelity system one sub never works well for a multitude of reasons. When you get to two subs crawling around on all fours is an evolutionary step backwards and totally unnecessary. Sub placement has to consider the placement of the satellites. Whether or not you add more subs in addition and where you place them depends on what type of satellites you have, point source or line source, size of drivers, how high you intend on crossing over and how loud you want to go. Subs should always be against a wall or in corners. There is a large increase in efficiency which lowers distortion and the amount of power needed to drive the sub. It also decreases unfavorable room interactions. 

By far the most difficult problem is matching the subs to the satellites. If set up correctly you should not be able to tell there is a sub in the system.
There are three issues that have to be dealt with to get the job done right. The crossover point and slopes, the phase and time relationship between the subs and the satellites and the relative volume of the subs to the satellites. Subwoofers have a bad reputation in many quarters because getting all this right is not easy and I have not seen a single powered subwoofer that comes with the onboard flexibility to do this well. It becomes a trial and error ordeal. Passive subwoofers with outboard amplifiers and digital crossover systems have the power to do this very effectively in less than a human life span. Now I just pissed off everyone with a powered sub  🥺 Not to worry! You can use the amplifier in the subwoofer you just have to add an outboard crossover with the necessary flexibility. You have to get one anyway as very few subs come with a high pass section for the satellites and you will absolutely never get the best performance without one. 

Right. If we are talking about a 2 channel high fidelity system one sub never works well for a multitude of reasons.


I must have a magic sub.
I must have a magic sub.

And here I was thinking I had TWO magic subs..

@noble100 --

Hi, Tim

I think there are two types of people as dannard states but I would describe them a bit differently:
1. Those that realize we all perceive deep bass tones below 80 Hz as not directional and therefore utilize bass arrays to obtain excellent bass performance.
2. Those that believe deep bass tones below 80 Hz are directional, place a sub next to each main speaker to reproduce it and believe this configuration is responsible for their perceiving the deep bass below 80 Hz as stereo. However, they’re not realizing that their brain’s ability to associate the mono fundamental deep bass tones, below 80 Hz that are actually being reproduced by their L+R subs, with the stereo harmonics or overtones, above 80 Hz that are being reproduced by their main speakers, are the real reason they are perceiving the deep bass below 80 Hz as directional and in stereo.
In my opinion, an understandable misunderstanding by group#2 above. I don’t think it’s really a big deal, either, since both groups are ultimately perceiving the mono and nondirectional deep bass below 80 Hz as stereo.

It’s important to note that for bass to actually appear nondirectional a cross-over somewhat lower than 80Hz must be used. Most may apply no steeper than an 4th order cut-off, and as such (even with steeper cut-offs) residual information will be audible above a, say, 80Hz cross-over and quite easily render sub sources directional. A mono-coupled DBA set-up will thus require a fairly low cross-over, indeed dictate it for best results, and from my chair it’s an undesirable and limiting demand being my preference is for main speaker/subs constellations to be crossed higher, typically between 80-100Hz (which also means high-passing the mains). For this dual sub set-ups work wonderfully, insofar symmetrical placement of the subs close to the mains is upheld for best possible integration and overall balance.

It’s not about being uninformed sticking to dual, symmetrically placed subs (close to the mains) - preferably large, at that - but a choice based on preference; indeed, why do I prefer a higher cross-over between the subs and mains in the 80-100Hz region? Because I find it usually sounds better, plain and simple, and here stereo information is suddenly a factor as both it and directionality are factors from sub sources crossed no lower than 80Hz, with residual information from those sub sources audible beyond 100Hz.

Moreover: if this (i.e.: DBA) was truly about physics and adhering to that, it’s conspicuous that the sheer size and displacement area of subs isn’t taken more into consideration. This as well is a huge factor, and what may seem overkill to some in this regard is only just an approximation to sufficient headroom to others, with lower distortion and cleaner bass to boot.

May I offer yet an alternative summing-up (and this is not as much implied by or addressed at your contributions on the matter, Tim, as that from others):

  1. Those that staunchly believes DBA subs set-ups is the one solution to end them all, and that the people who do not abide by this or otherwise shares this view, exclusively, are, more or less, stubborn dim wits.
  2. Those that maintains that what sounds best sounds the best, be that whatever configuration it takes - also one differing from a DBA.
Different ways to skin your cat, as they say, and not least: the proof is in THE EATING OF the pudding.
¨One need not be a bass player to be inspired by Geddy Lee.¨                     @audiokinesis But Geddy Lee does not connect his bass to bass cabinets, he connects them to laundry washing machines, check the videos... just kidding.  Thanks so much for the Swarm ideas, I,m about to complete a swarm like system. I already have a two Vandersteeen 2wq subs (active)  on my system.  I just bought locally a pair of B&W CT SW10 passive subs which are 4 ohms each.  A Dayton Sa1000 amp should be arriving in the next few days.  I understand that the passive subs should be wired in series in order to not overload the amp. Any other recommendations in to completing this DBA into my system,  My main speakers are Gradient Revolutions (dipole bass)which have already a 80hz high pass between pre out to amp because of the way the Vandy subs work. I will be using the other pre output for the Dayton amp. i will appreciate any recommandation you could give me. Thanks a lot