Distributed Bass Array configuration

I think that if the DBA system is integrated properly it affords one the ability to integrate bass effortlessly, no matter the listening level, which is highly appealing to me.

The beauty of DBA is the "integrated properly" happens almost automatically. With one sub it is impossible, the peaks and nulls are unavoidable and draw attention to the bass. With four they are so small and smooth the bass disappears, the subs disappear, and all you are left with to "integrate" is their level. 

When it comes to that, there is no escape from the reality of human hearing. Equal loudness contours are a thing. DBA is no magic bullet.  

It does however get a lot closer to what you described. With normal no, one, or two sub bass the really low bottom end either falls off to nothing, or else you have way too much above that. Either way you notice big changes with volume. With a DBA the contours are still there but nowhere near as big a problem due I think to the smoothness factor. 

What I did, once the initial phase is done, was listen to a lot of different music at my normal levels. I abhor meters. Most of the time I listen at a nice satisfying volume level. Sometimes not that loud. Occasionally I listen Supertramp Loud. Gradually, over time, I make really small level adjustments. Really small. Like I turn the knob but about half the time not really sure it did anything. This works because the meaning of the equal loudness contours is we go from being relatively insensitive to bass at low volume to hyper sensitive to bass at high volume. The same 2dB change in other words seems completely different (a lot more) from 98 to 100dB than from 88 to 90.   

Took a while, but most of the tweaking was in the first few weeks and now it is pretty close to what you said, effortless no matter the listening level. Never quite gets there, but close enough I never give it any thought any more- until it comes up like this. 

ieales,

     I get similar results from my 4-sub DBA as millercarbon, seemingly effortless bass that is seamlessly integrated with my main speakers regardless of volume level, that is as solid, powerful and dynamic as the source content dictates.
     Bass smearing and bass masking of midrange frequencies occurs when the deep and mid bass frequencies are accentuated, meaning the lower frequencies are artificially boosted, are not in relative balance in volume intensity with the rest of the frequency spectrum and, therefore, not accurately and faithfully reproducing the recorded source recording.
     Of course, this assumes the source material was well recorded with the full frequency spectrum in accurate and natural relative balance without any frequency portions being exaggerated or attenuated.
     Whether a 4-sub DBA system over emphasizes the bass frequencies, resulting in smearing or masking of the midrange frequencies, or accurately and proportionally reproduces the bass frequencies, resulting in no smearing or masking of the midrange frequencies, is completely determined by the user’s sound quality preferences and the subsequent sizing, positioning and configuration of the DBA system.
     The specific size and bass output capacity of the subs utilized, the specific positioning of the 4 subs in the room, along with the specific volume and low pass crossover frequency settings, allows for a wide range of bass reproduction options which, as a result, allows for a wide range of overall system sound quality permutations. Flexibility and scalability are just another couple of advantages of the DBA concept.
     For example, my overall system sound quality preference is accurate, detailed, dynamic, well balanced and natural. My 4-sub DBA system, the Audio Kinesis Debra model, utilizes relatively small, 1’wx1’dx2’h,subs that are rated at 4 ohms and have 10" drivers. My room is 23’x16’ with an 8’ ceiling.
     Based on my overall system sound quality preference for high quality, I positioned and configured my DBA system so that the bass would be perceived in the room as being accurate, detailed, solid, powerful, dynamic and well balanced with no portion of the audible frequency spectrum accentuated above another.
     I accomplished these goals, of optimum bass quality rather than bass quantity, with the DBA’s bass by positioning 2 of the subs along my front 16’ wall, with each at opposite ends about 1’ in/away from each corner. I positioned the other 2 subs toward the rear of the room, with one placed along each of the 23’ side walls and, again, about 1’ in/away from each rear corner. I also placed 2 stacked GIK Tri-Trap bass traps in all 4 corners of my room.
     Avoiding placing any of the 4 subs in corners and utilizing multiple bass traps in all corners is a good start. But my goals also required the proper configuration of the DBA system for my overall system sound quality preferences to be attained. I precisely matched the volume of the DBA to that of my main speakers, running the mains full range down to their rated bass extension of only 35 Hz, and set the low pass bass filter to 40 Hz.
     The result? Music and HT reproduction that is accurate, detailed, solid, powerful, dynamic, well integrated and well balanced with no portion of the audible frequency spectrum accentuated above another.
     The only exceptions worth mentioning occurs on some HT Blu-Ray discs during LFE channel reproduction when the DBA’s bass can become so decidedly unbalanced and overwhelming that it shakes the seats and walls in the room to very enjoyable and satisfying levels.

Tim

I'm almost always talking about my DBA in terms of music. But I have to say, the effect with movies is if anything even more impressive. A good movie soundtrack through a high end stereo with a DBA is really something.

Why is there never any mention of level matching these DBA systems with the main speakers using an SPL meter? Otherwise, wouldn’t it just be guessing what the volume level should be on the subs?