Dual vs single sub

Hi Tim,

    I have two Kinergetics SW-800s (each has five 10” Seas drivers in their own enclosures wired in parallel) driven by a Pass Labs X-250 and two SVS SB-16 Ultras in my room. I have an active set up using a Mac Mini maxed out with SSD drives using JRiver playing lossless FLAC to my mini DSP via optical out. The mini DSP is processing 24/96 with 8 balanced outputs with 12 biquad filters on each channel which were created using REW and MSO. My main speakers (Magnepan 20.1’s) run full range. Highs/Lows of each Maggie have their own channels (4) and each sub has its own channel (4). 

To tackle the Herculean task of attaining perfect base I have spent almost as much money on my subs as my 20.1s. That is how much I believe it is important to get this aspect of the system correct. Proper base is essential to all music, I want a tympani to sound like it and make my chest reverb with a strike as it did when I played in an orchestra. Lower octave listening, even the vibrations you can’t hear but feel are foundational to the live experience. Those waves are dissipated in a concert hall but build up in a room and bloat the sound unless it’s done right. I’ve heard a lot of excellent systems and many top of the line speakers will not tread near 16Hz because they know it will be a mess in most rooms. 

While i get that many people will not go to my extreme to get perfect base having 4 subs of reasonable quality disbursed in the room can really make a system sound complete. When properly set up the bass is tight and integrates seamlessly into the system.

The most common statement upon seeing my set up is, “I bet you could blow out the window with that! Why do you have so many big speakers?” “It’s for accuracy,” I say and then ask to play their favorite piece of music. The first impression in listening to my system from non audiophiles is how “clear” the music is and that has everything to do with proper bass integration and room correction. I can turn up the volume to concert levels and it doesn’t seem “loud.” Yet when watching a movie where a tank rolls by the ground shakes, your gut gets a strange felling and  stomach makes a flip just as you would if you were standing next to it; shots hit you in the chest and make you jump. 

I agree with you. I can talk all day about how important it is but hearing is believing. All of this is not that hard to set up either. I followed a tutorial on REW and made some measurements. Did another tutorial in MSO when I was learning and plugged in my own data after seeing how it worked using the tutorial files. Spent a day having fun adding and refining it. It’s so exciting to experience how big a difference is realized when room correction is done right with an integrated sub system. 

My last piece of my system will be BACCH for Mac. . . Saving up my coins now!  

Happy Listening,
Steve

@millercarbon --

The Ford Motor Company did a study some years ago, to determine what exactly was needed for really good bass. What they found is that below something like 80 Hz the bass on virtually all recordings is mono.

I just got my Swarm-based distributed bass array up and running last night and so I can now say from factual actual experience there is nothing else like it. If you want really good bass you will use FOUR subs distributed around the room. Period.

Why try and make a case with a limited number of CD’s (what genre, age of mix, etc.?) to conclude that there’s virtually no recorded true-stereo bass? It’s the problem of induction all over again, and a neatly sought closure to support an argument that may know full well the problematic issue of playing stereo information from sound sources (i.e.: subs) that aren’t placed symmetrically to the mains, insofar they’re crossed high enough for it to matter (which, I’d wager, could be an issue even if crossed below the rigidly fixed 80Hz). So, mono is the solution, preferably crossed rather low for the 4-sub approach to make the best of it, timing with the mains being the lesser concern and not drawing on the potential benefit of high-passing the mains (from ~80Hz or so on up to make the most of it). At times this even boarders on the scent of a subwoofer inquisition that calls heresy on anyone who’d dare not to see the divine light of multiple subs.

Fore sure, multiple sub sources scattered throughout the listening room in mono can sound absolutely great - the latest of which I’ve heard comprised no less that 6 Front Loaded Horns each fitted with a 15" driver tuned at ~25Hz (20 cubic feet cabinet volume per horn), and it was a blast both in quality and quantity (that is, 4 of them were placed front center from the ceiling in a cluster with all mouths facing each other to form a single mouth, while the last 2 of them were placed along the rear wall, so essentially this wasn’t a multiple sub approach as advocated here).

What really annoys me though is a prevalence to factualize a sub-approach (i.e.: the 4-sub mono one) as the one and only high quality solution, when there are other viable solutions like a 2-sub approach - in stereo, crossed significantly above 50Hz, and placed symmetrically to the mains. If mono-bass is your thing, or certainly the argument of it, then a pair of stereo-coupled subs will still play a mono signal as such, but if classical material or electronica in particular should muster up a stereo signal here for an intended effect or to support a spatial element, then true stereo-coupled subs placed properly (to the mains) will grant you this aspect of the music additionally.

Further I’d suggest being open to other principles than direct radiating subs, which are by far - dare I say exclusively - the bass principle of choice around here and audiophilia in general, perhaps even blindly. Horn subs aren’t really sold commercially other than from pro vendors, and while also being quite large it’s understandable many mayn’t have been exposed to their traits in a home setting, but this is also the problem: most simply don’t know how horn subs sound, and because of this (and their being used in pro-sector applications) likely make assumptions on their sound that are far removed from their actual imprinting. Quality horn subs, which are mostly available via DIY-solutions, to my ears sport a level of refinement, ease, smoothness and enveloping presence that no direct radiating solution that I’ve heard can equal, and this is obvious whether a multiple sub approach, 2 of them or even singles is used. While you would think first and foremost that a horn sub (some 30Hz extension minimum requirement for it to be called a ’sub’ and not just a bass bin) to be perhaps more of a more brutal, chest-slamming experience than a smaller DR solution (which it can be at elevated levels), you’re likely oblivious to the traits mentioned above that are prevalent at more normal listening levels as well (i.e.: 60-90dB’s, whatever floats your boat) - traits that should be considered and pursued by every audiophile.

So then, it’s not my intention to bash the multiple sub approach, which I know can sound great, but for some to ease up a bit on this being the only proper way to implement subs in your home setup. 

EDIT: one could of course combine a true stereo 2-sub setup with 2 additional subs in mono placed more "freely" in relation to the mains. 

phusis:
" Why try and make a case with a limited number of CD’s (what genre, age of mix, etc.?) to conclude that there’s virtually no recorded true-stereo bass?"

Hello phusis,
     I don't believe it was millercarbon who tried to make a case that there's virtually no recorded true-stereo bass content.    I think it was Audiokinesis/Duke who mentioned the rarity of recordings with stereo bass earlier on this thread.
    I know that his AK Swarm and Debra distributed bass array systems, with the addition of a 2nd Dayton sub amp, is capable of being positioned in a manner that would successfully reproduce stereo bass.
    If I recall correctly, however, Duke stated he wasn't aware of any content containing true-stereo bass and asked if anyone else knew of any content recorded with true-stereo bass.  I'm not aware of any and apparently no one else reading this thread is, either.  
     You seemed a bit offended when you mistakenly thought millercarbon had tried to make a case that there was just a 'limited' number of cds containing true-stereo bass when there appears to be none.      
     Are you aware of any recorded content with true-stereo bass?
     Just to be clear, I know it's very possible to attain very good bass response at a single sweet spot location using 2 good subs.  My point is that it will be very good mono bass, not true-stereo bass.

Tim

@audiokinesis --

The distributed multi-sub approach has nothing to do with whether or not the mains are highpassed. Those are two separate decisions. I’m probably the one who caused the confusion because I’m a distributed multi-sub advocate but not an advocate of automatically high-passing the mains in every situation. I think it depends on the specifics.

I know, Duke re: multi-sub approach and high-passing mains, but I brought this into the mix, so to speak, because it's my impression the general gist with multi-sub use is to cross fairly low to the mains (i.e.: without high-passing them), not least taking into account the directionality at higher frequencies and how this could be seen as an issue with subs scattered throughout the room around the listener. 

I did refer to high-passing the mains as a "potential benefit," which is also a way of saying that I side with your view on how it "depends on the specifics." 

The distributed multi-sub approach apparently works well in many situations, but is not the only approach that works well, and in some situations it would not be the approach I'd choose. It depends on the specific situation. 

I believe this has always come across rather consistently from your writings, certainly implicitly, contrary to other advocates here of the 4-sub approach who seem quite adamant of it being the only true quality solution, so much indeed that considering otherwise is "not getting it." Again, I've heard great 4-sub setups, no contention here, but I believe a symmetrically placed 2-sub setup can make wonders as well.