mcreyn’s response to s200cr’s statement about just buying speakers that don’t need subs:
" Why? The best speaker placement for imaging and bass are generally mutually exclusive!!!!! Are you willing to place 4 main speakers around your room at the optimal positions to minimize standing waves (ala a swarm setup)? Show me a full range speaker system that can go flat below 20hz that costs less than $10,000 a pair and is optimized for placement in the bass where the imaging is the best. The system in my office (a used set of Totem Mites and a Rythmik L12 for a total cost of $900) does that comfortably (when I say comfortably, it starts to roll off at 23 hz is and 1 db down at 20hz)."
Great response, mcreyn, I was about to post and make many of the same points before I read your response. I just want to add a few thoughts to further emphasize your thoughts: My opinion and suggestion is to approach the setup of your home audio system as 2 systems: a bass system and a midrange/treble and sound stage illusion system.
The first step is to get the bass sounding right. As I’ve stated previously, I believe buying and properly setting up an Audio Kinesis Swarm or Debra system is the simplest and most reliable method of achieving this if you have the funds ($2,500-3,000) and room space. But, for those on a stricter budget, here are my suggestions for optimizing bass in your room based on number of subs you’re able to afford:
1. No Subs/just the bass drivers in your main speakers- As mcreyn has accurately stated, the best speaker location for both imaging and bass response are highly unlikely, if ever, going to be optimized at the same room position. Full range speakers that contain bass, mid-range and treble drivers all in a single cabinet are, therefore, highly handicapped in their ability to provide good bass response and good imaging right from the get go.
Having a physically separate bass system that seamlessly integrates powerful and well defined bass response with physically separate main speakers system providing high quality mid-range/treble sound reproduction with a realistic sound staging illusion, even if there’s some bass frequency redundancy between the 2 systems, is an alternative solution that is highly superior in my opinion based on experience.
2. One Sub- With a single sub, unfortunately, the bass will be compromised because the bass will only be optimized at a single point in your room (your listening seat sweet spot) and the bass will not sound as good at other spots in your room. To optimally position a single sub, place the connected sub at your listening position/seat and play some content that contains several minutes of good and repetitive bass. Then, starting at the front-right-corner of your room, slowly walk counter-clockwise along the walls of your room until you find the exact spot where the bass sounds best to you. Lastly, locate the sub to this exact spot and then replay the bass content to verify the bass still sounds good to you when your seated at your listening position/seat.
mcreyn, Isuggest you may want to try this in your single sub office system.
3. Two Subs- 2 subs will give better results than a single sub because, if properly positioned, any bass standing waves at your listening position may be reduced or eliminated and each sub is reproducing only a portion of the total content bass. This increases the capacity of bass volume, impact and dynamics/headroom. To optimally setup 2 subs, the one sub setup above is used for sub#1 and then sub#2 is placed at the listening position/seat and the same procedure is used to locate the exact optimum room position, continuing the search from sub#1 along the room walls counter-clockwise.
4. Three Subs- 3 subs will as expected give better results than 2 subs by further increasing the capacity of bass volume, impact and dynamics/headroom. But 3 subs, if properly positioned, will also begin to significantly reduce or eliminate bass standing waves throughout the entire room, beyond just those at the listening position/seat. Walking around the room, specific spots where bass response is perceived as less than optimal will be noticeably fewer with 3 subs when compared to 1 or 2 subs. To optimally set up 3 subs, just follow the procedure for 2 subs above and then sub#3 is placed at the listening position/seat and the same procedure is used to locate the exact optimum room position, continuing the search from sub#2 along the room walls counter-clockwise.
5. Four Subs- 4 subs are required for achieving sota bass response in any room. Acoustical experts have statistically identified that 4 subs in a room as the threshold at which the vast majority of bass standing waves in most rooms are reduced or eliminated, with any additional subs only providing moderate and smaller marginal benefits.
In summary, the more subs you deploy in your room, the fewer bass standing waves will exist in your room and, as a direct result, the better your in-room bass response will sound.
I don’t consider myself a bass expert. I just read all the material I could find on-line and rely on my years of experience of striving for very good bass response in my systems; beginning with no sub and progressing to 1, then 2 and 3. All of my systems sounded very good to me but the bass always seemed compromised to varying degrees.
Then I read scientific White Papers written by a a couple of acoustical scientists, Dr.Earl Geddes and Dr. Floyd O’toole, about their results experimenting with distributed bass array (DBA) systems in commercial and home environments.
It all made good sense to me but I was resistant at first due mainly to the cost and concerns about accommodating 4 subs in my 16 x 23 foot room. But, after discussing at length the Audio Kenisis Debra 4-sub dba system with James Romeyn. owner of James Romeyn Music and Audio in Utah, I decided to to buy the complete Debra system for about $3K with a free 30-day in home trial period.
It took about 4-5 hrs for a friend and I to set it up carefully following the progressive sub positioning method and routing all 4 custom speaker wires in the crawl space below my living room.
Still relying on the concept of building my system as 2 systems, a bass system and a mid-range/ treble and sound stage illusion system, I considered the reproduction of bass frequencies from about 20 to 40 Hz to be solidly in place and providing the foundation for placing the remaining mid-range/treble and sound stage illusion system atop it. I use a pair of older Magnepan 2.7QR 6 x 2 foot panels, driven by a pair of D-Sonic M600M (1,200 watts @ 4 ohms) run full-range for this purpose. Whereas the Debra system provides sota bass response virtually throughout the entire room, the main speakers require careful placement to provide an accurate and musical portrayal of the remainder of the audio spectrum and provide an optimum .sound stage illusion at the specific listening position/seat sweet spot.
A benefit of treating your system as 2 systems is that, once your subs have been positioned, your main speakers can be located completely independently for optimum mid-range/treble response as well as for creating an optimum sound stage illusion. After considerable trial and error experimenting, I was able to locate each panel so that all performance parameters were maximized; this resulted in my panels being locted about 4 ft. away from my front 16 ft. wall, spread about 7 ft. apart on center and slightly toed-in angling toward and straddling my listening chair about 14 ft. away centered n my rear 16 ft. wall.
We initially auditioned it on ht by playing a Bluray copy of the movie Fury, a WWII tank film with Brad Pitt. Our first indication of how exceptionally well this system reproduces bass was during the opening trailers of a soon to be released movie on Bluray, Whiplash, that contained a solo drum soundtrack, recorded direct to digital and played back at 24 bit/96 Khz hi-resolution .digital through my Oppo 105 Bluray player., that was a driving beat that built to a final crescendo that had my friend and I staring at each other in disbelief with how spectacularly real and ’right there in the front center of the room’ the drum kit was perceived to be by both of us.
The WWII tank and heavy machine gun battle scenes in the movie, Fury, were also portrayed, with the assistance of my 5 other full range speakers in Dolby Digital 5.1 (5.4?)Surround Sound format, in an extremely realistic manner.
After the movie, we also auditioned a wide variety of music stored as 16 bit/ 44 Khz files of ripped CDs and some hi-res 24 bit/96 Khz WAV music files,stored on my NAS hard drive.
I find the entire music listening experience as being very immersive, with the width and depth of the sound stage illusion varying slightly in size, stability and overall realism depending on recording. I’ve noticed those recorded direct to hi-res digital are generally significantly superior in all 3 of these qualities.
To be clear, I’m not stating you cannot attain very good full range sound performance in your system using no or 1 to 3 subs.
What I am trying to convey is that the science is correct, utilizing 4 subs seems to pass a threshold that, due to the vast majority of bass standing waves either being reduced or eliminated, allows for bass response that is both powerful and well defined that far exceeds the bass performance that I was ever able to achieve with fewer than 4 subs in my room.
Sorry this post was so long,
Tim
