jazz99,
Woops, forgot about room correction. You can run bass room correction optimized to your listening seat as part of step#6 above. It should just further fine tune bass response at your listening seat but will have little to no affect of improving bass response elsewhere in the room.
Tim
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Hello jazz99,
For your situation, I'd suggest the SVS SB1000 (12"driver in a sealed box) would be the better choice than the SVS PB1000 (10" driver in a ported box) although either would provide a dramatic improvement over not using any sub with your Focal Aria 906 speakers.. They're both priced at $499 and are powered by the same 300 watt class D amp.
The PB1000 is slightly larger and generally considered better for movies and the SB is slightly smaller and considered better for music.
Your Focal bookshelf speakers on stands are only reproducing bass down to about 55Hz. The human audible hearing range is 20Hz to 20,000Hz, with 20Hz being the lowest audible frequency and 20,000Hz being the highest audible frequency.
Your current system is reproducing none of the frequencies on your music between 20Hz and 55Hz. Adding either SVS sub to your system will fill in this gap and you'll be amazed at what you were missing. I believe the SB1000 sub will reproduce bass frequencies in this missing frequency range more accurately and integrate more seamlessly with the sound frequencies reproduced by your Focals than the PB1000 sub can.
For best bass response in your system and room, it's also very important to properly and precisely position the sub in relation to your listening seat. Here's my suggestion of how to do this:
1. Disconnect your Focal speakers and place them and their stands temporarily outside your room. You can mark the positions of the stands on the floor (colored tape works well) or just optimize their positioning as a final step in this procedure.
2.Hook up the sub and place it at your listening position.
3. Play some music with good and repetitive deep bass.
4. starting at the right front corner of your room, walk counter-clockwise around the perimeter of your room and determine the exact spot where the bass sounds best to you. This is a critical step, so take your time and walk the perimeter multiple times if needed to find the precise spot that the bass sounds best to you (natural and detailed without being over-emphasized or attenuated).
5. Reposition the sub to the exact spot the bass sounded best.
6. Sit on your listening position seat and replay the music with good and repetitive bass. Verify the bass now sounds just as good here as it did at your identified spot. If it does, your sub is optimally positioned within your room. If it doesn't, you'll need to repeat this procedure from step#2.
7. Reconnect your Focal spkrs and place them on the stands at the marked positions or reposition them again in relation to your listening seat for optimum tonal response and imaging. I'd recommend running your Focals full range and connecting them to your amp as usual rather than connecting them to the SVS sub. There's also no harm in trying both methods and using whatever method you prefer.
8. Set the desired low frequency cutoff frequency on the SVS sub. This is an important step with the goal being the smooth and continuous blending of the sound from the sub and your Focals. This will probably require some experimenting with the ideal cutoff frequency likely being somewhere close to 55Hz.
I believe an ideal cutoff frequency setting could be determined mathematically if we had all the relevant data but you're likely to arrive at a setting that's very close just doing it by ear and what sounds most seamless to you. Try to avoid creating any holes in the combination's frequency response.
My opinion is that, when you have everything positioned and configured properly, anyone listening to your system from your listening seat will just assume you have the best sounding pair of bookshelf speakers they've ever heard.
Lastly, I want you to realize that this system will sound great from your listening seat but there is a compromise that cannot be avoided when only a single sub is used; the bass response will not be optimized at multiple other specific spots in your room. Less discriminating listeners will probably not even pick up on this unless they're sitting at a spot in the room where a bass mode exists.
Bass modes are specific spots in any given room where the bass will sound exaggerated, attenuated or even absent. I can explain bass room acoustics in more detail but I'd like to avoid turning this post into an even longer book.
There are bass systems that eliminate the vast majority of bass modes existing in a given room which results in very good bass response throughout the entire room but they're more expensive and require more subs. I use one of these systems, called a distributed bass array system, but I think it's too expensive ($3K) for your budget, more elaborate (4 SVS SB1000 sized subs with a separate 1K watt amp) than is practical for a small room like yours and not necessary if you're content with optimized bass response at a single listening position.
Hope this helped a bit,
Tim
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millercarbon:
"More pure gold. I’ve copied the whole post just to pose a pop quiz and see if anyone can answer: what one single letter best differentiates Duke’s highly informative post from all the rest?
Hint: to understand the answer is to understand the problem."
Hello millercarbon,
I completely agree with you that audiokinesis keeps delivering audio gold by sharing his vast audio knowledge and experience with his thread posts. I always learn a lot from his posts.
Now, your pop quiz question has me stumped:
What one single letter best differentiates Duke’s highly informative post from all the rest?
I really have no idea but I'll take a stab just for fun.
Is it 'G'?
As in g, I didn't know that.
Tim
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Duke,
Excellent explanation and it all makes perfect sense to me.
I was thinking, however, that I may understand better than some reading it since I’ve experienced the transformation of perceived bass response in my room by using a DBA (distributed bass array) system.
I think the practical consequences of designing a DBA system based on utilizing the principles you explained does not really become fully understood until an individual actually hears the transformation themselves.
I remember James Romeyn describing the bass response I should expect in my room from his Audio Kinesis DEBRA DBA system and thinking it all sounded too good to be true.
In fact, I recall being skeptical right up to the point I pressed play after setup was completed in my room. It didn’t take me long to know James was telling me the truth. My honest opinion is that the transformation of the bass response in my room to state of the art was nothing short of miraculous, especially considering it was affordable ($3K) and done without any mics, room correction, room treatments or other special equipment.
I know you’re too much of a gentleman to use a thread post as a sales promo for your own products so I’m taking the opportunity to do it for you and Jim as a very satisfied customer. Besides, no one ever accused me of being a gentleman.
I can state with certainty that the DBA system works extremely well whether it’s an Audio Kinesis Swarm or Debra complete system or a 4 sub custom configuration with subs of your choice.
My main point being that I could write a book on how well it performs and convince no one but it only requires a short audition to prove to anyone. To mangle an old expression, a listen is worth a thousand words.
Tim
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millercarbon,
I'm glad you're becoming a believer in the distributed bass array concept but I'm a little confused, have you decided to buy an AK Swarm or Debra? Or have you decided to build your own custom DBA?
Whatever you decide, I'll be happy to help you out.
I set my Debra DBA system about 3 yrs ago and I'm still grateful every day that I did because I truly believe the bass response in my room is state of the art for music and ht.
As Duke and I've said before, there's really 3 good methods you could use to set up a DBA: 1. Buy the Swarm, 2. Buy the Debra or 3. Buy 4 subs of your choice and setup a custom system. Both the Swarm and Debra are excellent bass systems and come with everything you need except for a interconnects and speaker wire. But if you want the ultimate DBA, you could buy 4 top of the line subs and just follow the positioning procedure.
I have little doubt a custom DBA with 4 top of the line subs would outperform either AK DBA but it would likely cost at least 3 times as much and the subs would be larger and more intrusive.
Let me know if you'd like my assistance either on this thread or pm me.
Thanks,
Tim
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Hello millercarbon,
Very exciting, sounds like you have a good plan. It seems like you're off to a good start with the drivers, amps and enclosures already having been delivered.
I'm glad to assist you as much as I can. However, I think you should know that my main areas of knowledge and experience are as a DBA system room configuration person and user. Unfortunately, I have little knowledge and experience with DIY electronics and speaker projects. I wouldn't describe myself as totally useless in these areas but I'm certainly in that neighborhood. I'd suggest you rely on Duke's or others' advice on these matters. If I do offer advice in these matters, I'll be sure to qualify it with an accurate estimate of my degree of certainty.
Here are a few thoughts I've had thus far:
1. Don't forget the footers, spiked for carpet and something softer for a hard floor. Mine have 3 screw-in spiked footers on each sub that work fine on my carpet. There's no wobble at all with only 3 footers but it's your choice whether you want to use 3 or 4.
2. The Debra subs have the speaker terminals on the bottom of each sub but, according to a photo of your sub enclosure, their terminals are on the back.
Remember, your subs will be positioned facing the nearest wall and just about an inch away from it; this means the back, 2 sides and the top of each sub are the only visible portions. My wife loves this because, if the wood is finished well, these subs look like elegant and stylish wood pedestals like those seen in fine stores and galleries. Any visible speaker terminals and connected wires will ruin this sleek and stylish look. She normally has either a vase of fresh flowers or some other smaller objects she thinks looks good highlighted on these .
.
3. You said the amps (plural) were delivered. How many did you buy and did you purchase the same dedicated Dayton sub amp that comes with the Swarm and Debra?
4. The Morel 10" woofer looks very nice, especially when you get a free sub enclosure with each. The only possible issue I see is that these drivers are 8 ohms while the 10" drivers used in the Swarm and Debra subs are 4 ohms. I believe the class AB Dayton subs double their output wattage as impedance is halved from 8 to 4 ohms, from 500 to about 1,000 watts. This is a good subject for you to discuss with Duke to understand how this could possibly affect performance.
I faintly recall at least one of the subs having dual sets of + and - terminals with the others just having single sets of terminals. I think you should check with Duke on the internal wiring of the subs with dual sets of terminals and how many subs should have dual terminals and how many should have single terminals. I know the subs are wired in series and I'm about 70% sure this affects the actual impedance the amp recognizes. I should be able to find the instruction sheet for my Debra system for relevant details and let you know.
That's about all the topics I thought you should be aware of thus far. If you'd like, I can offer more thoughts as your custom DBA project progresses.
Later,
Tim
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vtvmtodvm:
"One of the major benefits to be derived from the addition of self-powered subs (use at least two, generally spaced wide, and towed-in from the front wall corners) is that they’ll help you defeat room mode peaks/nulls. They’re the next best thing to 4 inch thick broadband bass traps."
Hello vtvmtodvm,
Your statement is phrased as if it were factual or at least something agreed upon by a consensus of acoustical experts or experienced home audio enthusiasts. Based on my knowledge and experience, I believe your statement is merely your personal opinion, is mainly demonstrably false and should be completely disregarded by anyone trying to attain good bass response in their rooms.
It has been proven that using a single sub in any given room can provide good bass response at a given single position in the room if properly positioned but the bass response will also be very poor throughout most of the remainder of the room due to the large number of bass room modes generated by a single sub (heard variously as spots of bass exaggeration, attenuation and even bass absence).
Adding a second and third properly positioned subs to the room begins to gradually reduce the number of bass room modes which not only increases bass quality and impact at the assigned sweet spot but also begins to improve bass response throughout the remainder of the room. Doctors of acoustical engineering, Earl Geddes and Floyd O’Toole, have discovered and verified that having 4 subs properly positioned in a given room (in what they call a distributed bass array system) will eliminate the majority of bass room modes and provides excellent bass response throughout the entire room, making any position in the room a bass sweet spot.
I use the Audio Kinesis Debra 4 sub distributed bass array system in my 23 x 16 x 8 foot room and can verify this system definitely provides state of the art bass response throughout my entire room.
I wanted to point out that placing subs in the corners of your room should definitely be avoided since this will produce exaggerated bass and only multiply the number of bass modes existing in any given room. I’ve actually never heard of any benefit gained by toeing in subs in corners.
As to bass traps, mics, room correction and parametric equalization, none of this is required with a properly positioned 4 sub distributed bass array system.
I don’t currently have the time to monitor the rest of your post for other misinformation, I never advanced past your first paragraph, but will try to do so soon.
Tim
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Hello again Duke, I'm very grateful for your many contributions on this thread sharing your very relevant knowledge and experience concerning how to attain very good bass response in our home music and ht rooms. You've mentioned 'real world' examples and it made me think that's exactly what I consider myself to be. So, I thought I'd give some details about my speakers, room, how my 4 Debra subs are positioned in my room and the results just as a real world example for illustration purposes in case it might help. My combo 2-ch music and ht system is in my 23 x16 x 8 ft. living room. I have a large hdtv centered on the front 16' wall with a Magnepan CC3 center ch spkr wall mounted just above the tv and a pair of Magnepan 2.7QR speakers straddling the tv, about 8'apart and 3-4' away from the front wall. Here are the important specs on the 2.7QRs: 6' x 2' 3-way planar-magnetic panels QR tweeter : 1½″×56″
midrange : 98in²
woofer : 620in² 34Hz-26kHz ±3dB 87dB/2.83v/m @500Hz Low-Pass 12dB/octave @ 650Hz
Band-Pass 6dB/octave @ 500Hz-950Hz
High-Pass 6dB/octave @ 950Hz
bass inverted 2 of the AK Debra bass system's subs are positioned along the front 16' wall, one about 2' away from the left-front corner and the other about 2' away from the right-front corner with both behind my main spkrs and the 10" drivers facing the front wall and less than 2" away from it. The remaining 2 subs are placed along the 23' side walls, one on each wall about 2' away from each rear corner. All 4 subs are run in mono and powered by a single class AB 1K w Dayton with the cutoff frequency set at 40Hz. I experimented with the phase control, slowly adjusting it from '0' to '180' and back again numerous times while listening for subtle improvements in the bass response. I failed to notice any changes so I set this control to '0' (in phase) and proceeded to the next setup step. Once all 4 subs are setup, the instructions call for sequentially reversing the polarity on each sub to determine if the in-room bass response is perceived as improved with the polarity reversed on one specific sub of the 4. If I recall correctly, my friend helping me and I were both tired at this point and we both couldn't imagine exactly how the bass could be improved, so we never completed this step on setup day or since. It's been 3 years now and I still can't imagine how the bass in my system could be improved. Since everyone who's ever listened to my system, including my friend and I, believes the bass is sota, I'm thinking there's no good reason to mess with it now and possibly jinx it. My current opinion is that the DBA system is the best method to achieve sota bass response in any room and it will be able to integrate seamlessly with any pair of main speakers. I know I'll never need to buy another bass system again and I can use any pair of speakers I want with it in the future. The DBA concept honestly does perform that well and it costs about the same as 2 high quality subs. I also believe this system has a high WAF factor in my medium sized room. Tim |
russmaleartist,
Exactly, your description of what a good sub or subs integration should do and sound like, and not sound like, is just as my expectations. On my bass system, the subs are completely silent as long as there 's no music or ht content that calls for any reproduction of frequencies at or below 40Hz. They're like an elite group of very stealthy and extremely capable bass soldiers that never give away their presence but are constantly alert, awaiting the agreed upon signals being sent before instantly springing into coordinated action, precisely performing actions with the proper application of force necessary to accomplish the mission, before returning to stealthy but alert silence once again and awaiting their next call to action. How's that for hyperbolic but accurate fun?
I believe a good sub system is not meant to be constantly heard but just when the content calls for it. In my experience, attaining this quality requires playing a wide variety of content and fine tuning the crossover frequency to be as low as possible but not low enough to prevent their contribution when needed. I've come to the conclusion that it's really just a balancing act with the best hoped for outcome actually being more of an approximation. But it's also true that a good cutoff frequency setting approximation will be perceived as seamless integration with my main speakers 90% of the time.
Conversely, setting the crossover frequency too high on a sub or sub system, imo, could be the most common and detrimental mistake many individuals make with their systems. This only results in the subs being constantly heard and a perception of the bass being disjointed and not well integrated with the main speakers.
What particular crossover frequency is considered 'too high' is subjective but I think most people will know it when they hear it.
I'll just state that, if you're constantly aware of a sub's or sub system's contribution, the crossover is definitely set too high.
Tim
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millercarbon,
I just recalled something about the Audio Kinesis Swarm and Debra that Duke knows more about than I do; there's something called 'bass room gain' that needs to be compensated for when setting up a distributed bass array system. I believe it's a 3 dB increase in the volume of deep bass frequencies in typical rooms using subs that is the result of acoustic interactions in the room itself.
I know Duke somehow compensates for this so that the in-room bass response is flatter and more accurate but I'm not certain of exactly how he does this. Hopefully, Duke is still following this thread and will respond. If not, I suggest you pm him and ask.
Sorry I didn't recall this earlier but I think it's important for your custom DBA build.
Tim
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millercarbon, Excellent, I'm glad you've got the room gain factor covered with Duke's help. Duke, I think I might have gotten a bit lucky when I setup my 4 Debra subs in my room. I took all the port plugs out at initial setup with the intention of auditioning the system as all 4 running as ported subs first. If I didn't think it sounded very good, my plan was to plug them all and audition the system again as all 4 running as sealed subs to determine if this performed better. If I wasn't pleased with all subs ported or sealed, I figured I could try various combinations of ported and sealed. The reason I think I got a bit lucky is because it sounded almost unbelievably good with the first content my friend and I decided to audition it with, a bluray disc of the movie Fury. The first real test came with a preview of the movie Whiplash on this disc that included a drum solo that sounded so amazingly accurate and lifelike that it actually left my friend and I just looking at each other in stunned disbelief. There was an effortless quality to the bass while at the same time a sense of unlimited capacity to the dynamics which I'd only previously experienced with live music.The quality of the bass, as the tempo of the drum solo began slowly at a normal volume but kept gradually building in tempo and volume, was so pitch and tone perfect, accurate and detailed that there was no hint of betrayal in the solid and stable sound stage illusion that there was a guy expertly playing a full drum kit positioned dead center along my living room's front wall. The only accurate way we were able to describe this high a quality level of reproduction was to call it state of the art. I've been enjoying the Debra system's sota bass response for about 3 yrs now. I thought you might find it useful to know that I still have all subs configured as ported, with all in mono and powered by the single Dayton amp with the crossover freq. typically set at 40 Hz,no polarity inverted on any sub and my main speakers (with useful bass only to about 36 Hz) running full-range. The integration between the deep bass of the Debra system with the upper bass to treble of my large Magnepan panels is seamless. I know the above may sound like a bunch of hyperbole to many reading this because I would probably be highly skeptical reading this good of a review myself if I didn't hear it for myself. I completely agree with the thought of trying to audition a properly setup DBA (distributed bass array) system prior to buying a complete Audio Kinesis DBA system for $2,800 like I did or building your own custom DBA system like millercarbon is currently doing for possibly less money. I could probably write a book about how great the AK Debra system works in my system/room and convince nobody but I could probably also give a brief audition of it and convince anyone. Since my intention is just to spread the word to fellow music and ht enthusiasts about how exceptionally well DBAs actually perform, however, I have had some concerns about whether the DBA concept really is effective in virtually any given room. If I recall correctly from reading Earl Geddes's White Paper on this subject, I believe he even uses the phrase "in any given room" but I'm going to recheck just to be certain. I definitely know it works in my room and fairly certain it also did in the Absolute Sound reviewer's room since his review description linked below of the Swarm DBA system in his room so closely resembles my experiences of the Debra DBA system in my room. www.theabsolutesound.com/articles/audiokinesis-swarm-subwoofer-system/ As I think you're aware, I was convinced to buy the Debra system by your colleague James Romeyn's generous offer of a full refund option after a 4 week in-home trial period. Of course, it didn't take long to not only know I wouldn't be returning it but that I'd never need to buy another sub or bass system in my lifetime. I now have sota bass response but the Debra is still the only DBA I've ever personally setup and the only DBA I've ever personally even listened to in my system and room or any system and room. I prefer to make statements and offer opinions that are accurate, truthful and not exaggerated. I respect the obvious knowledge and experience you and James both possess concerning DBA systems and just have a couple of clarifying questions. Are you or James aware of any DBA systems not performing well in any room or system? Are either of you aware of any DBA systems not integrating well with any particular brand, model or type of speakers? Thanks, Tim |
Hello plga,
I think you may also want to consider the SVS-SB1000 subs that go for $499 each. I know SVS regularly ships to international destinations and would accept returns from Argentina, even though I know you'd prefer not to bother. But you would get almost $1,000 back to put towards another pair of small subs like the KEF Kubes just in case they didn't work well for you. The SB1000 are small (13-1/16"W x 13-1/2"H x 15-5/8"D), have powerful 300 watt class D built-in amps , go down to 24 Hz, weigh 27 pounds and have a 5 year warranty.
These subs do accept speaker line connections from your amp but you'll get varying opinions on the importance of this to sound quality. The main idea is the sound qualities of your amp will be imparted on both your main speakers and subs when both are fed signals from the same amp. I've heard REL subs hooked up via the amp and preamp methods and didn't notice a significant benefit of the speaker line method, but others claim they do and you may be able to notice an improvement, too.
However, there's also a benefit to connecting the subs via the alternative preamp method. You could run a single rca cable from each L+R channel output on your preamp to each L+R sub input and then an rca cable from each L+R sub output to each of your L+R inputs on your main amp.
Each sub has a built in crossover with a filtered rca line output (fixed at 80Hz, 12 dB/per octave high- pass. This method means the subs would reproduce the bass at 80 Hz or less (or whatever frequency you set the low pass filter on the sub to from 50 to 150 Hz or less) and your main speakers would be freed up to just reproduce frequencies of 80 Hz and up. I have heard significant improvements in the sound quality of the main pair of speakers when they're freed up from reproducing any deep bass signals. I believe these sound quality benefits are much more obvious to most people, imho, than the less significant improvements gained by using the high level speaker line connection method provides.
There's also another option using line-level rca cables connecting your preamp to the subs that entails running your main speakers full range and adjusting the subs low pass crossover frequency by ear until it sounds best to you.
The main point being that you have a wide range of hookup methods with the SVS SB1000 subs to experiment with in your system. This means your probably more likely to find a method that sounds and works best for you.
Tim
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Hello Chuck,
I was sort of adding your costs up in my head and thought it might of been less to buy a Swarm but I didn't want to ruin your fun. Anyway, you're going to have the only Swarm Deluxe Morel Special Edition....in Rosewood!
Possibly setting up next weekend? Wow, you're fast. I also just realized I don't know anything about your room and the rest of your system. Do you have time to describe?
Thanks,
Tim |
Hello rauliruegas,
Yes, I agree that attaining good, low distortion bass response performance in your room and system is very important not only for maximizing the accuracy and realism of reproduced music but also optimizing our enjoyment of it. Once I began using a 4-sub distributed bass array system in my system, I noticed there was a lot more musical details present in the bass region on good recordings that I didn't previously realize were even there.
It's much more difficult to attain good bass response in most rooms than it is to get good midrange and treble response, mainly due to the physical sound waves of bass frequencies being much longer and behaving differently than the much shorter midrange and treble frequencies' sound waves in the same room.
Because of these facts, I currently believe high quality audio systems should be considered 2 separate systems; a bass system and a midrange, treble and stereo imaging system.
My system building approach has evolved to getting good bass response in the room as the primary and initial goal. My current opinion is that a 4-sub dba system is an excellent and almost guaranteed method of achieving this goal but I think it's important to mention it's not the only method, especially if an individual only requires very good bass response at a single 'sweet spot' listening seat. A properly setup 4-sub dba system requires no room correction software or hardware, minimal equalization and zero bass room treatments. However, all are optional except bass traps, if these are deemed necessary then the dba was most likely not positioned properly.
Once the bass system's response has been optimized in the room, the next goal is the easier and more familiar step of optimally positioning the main l+r speakers in relation to the dedicated 'sweetspot' listening seat for best midrange response, treble response and imaging along with any non-bass frequency room treatments deemed necessary.
Tim
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rauliruegas,
I think those Evolution Acoustics mm-series twin self-powered sub towers certainly look impressive and like they'll reproduce very good bass.
I believe it's possible to get very good in-room bass response in most rooms at a specific dedicated but relatively small section of a given room usually referred to as a 'sweet spot' with only 2 subs regardless of size or price. I believe that low distortion bass is beneficial if the bass is still perceived as low distortion/accurate bass once the bass sound waves are launched into the room, some of these bass sound waves arrive unaltered directly at the listening position and other bass sound waves arrive at this listening position altered after reflecting/bouncing off of 1 or more room boundaries and the brain processes these multiple bass sound waves, arriving within milliseconds of each other, by summing them.
Once the 2 subs are properly positioned properly in the room to provide good bass response at the dedicated 'sweet spot', however, the bass response will not be consistently perceived as good throughout the entire room. The bass will be perceived as exaggerated, attenuated and even non existent at various specific spots in the room where room bass sound waves meet.
I also suggest you may have been too trusting of information produced by Velodyne's marketing department concerning the audible difference between bass sound waves produced by one of their self-amplified subs versus those produced by a competitor's passive sub powered by a good quality external amp.
Getting very good in-room bass response is definitely not as simple as buying the 'right' brand and model subs and plopping them down at convenient positions in the room. Principles of physics, psycho acoustics, the material composition of room boundaries (walls, floors and ceilings) and even the physical dimensions of the room itself are all important factors in a dynamic environment.
Tim
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millercarbon,
I own that Leonard Cohen/Jennifer Warnes Famous Blue Raincoat cd. The Bird on a Wire track does have some very good 3d imaging with those drums/bongos. You said " each whack sounds individual, each drum stays put in each location. My Swarm is two amps stereo but I tried it one amp mono with the same degree of imaging".
I think it's very interesting and telling that you heard the drums at the same positions within the 3d sound stage illusion whether you ran the bass in 'stereo bass' or 'mono bass'. My Debra dba system is all 'mono bass' using a single mono amp to drive all 4 subs and I perceive the drum whacks the same way on my system as you described on your system.
My experience is that combining a very good mono 4-sub bass dba system with a very good pair of stereo speakers for the mids and treble results in a very natural, very realistic, palpable full range sound stage that I perceive as stereo and lif-like from top to bottom.
This supports the theory, which I believe we both agree with, that the higher frequency harmonics of those bass drum whacks reproduced by our l+r main speakers provides the necessary spatial clues to determine exactly where the individual bass drums are located within the 3d sound stage image. Our ears receive the bass sound waves from the subs of the fundamental tone of the drum being struck first followed very quickly by our ears receiving the upper bass/lower midrange sound waves from the mains of the harmonics. Then our brains process these inputs, associates the fundamental tone/note with its fundamentals and is able to determine precisely where the drums are located within the 3d sound stage it also created with the assistance of the combination of the 2 unique channels of stereophonic sound.
Voila, psycho acoustics in action.
Tim
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Hello millercarbon, Very interesting. Vinnie Colaiuta: He played that drum track in one take and I just smiled real big and said, "There’s my drum track." Cool. I've discovered a lot of music transferred from analog reel-to-reel masters to 24 bit/96Khz digital WAV or FLAC files sound very good, no big mystery why since they're really just exact copies of the original masters. The best recordings I've found thus far, however, are ones recorded live in a well miked and good studio setting direct to digital. This online company is a good example of this:
https://www.soundliaison.com/
Tim |
Hi Chuck,
I was just wondering if we hijacked this thread. We haven't heard from the OP. jazz99/Paul, for awhile now.On his last post on 3/1/19 he stated: "I suppose one has to make a decision at some point, so will try to decide (after auditioning) between the SVS SB1000 and the JL Audio Dominion D110, which is unfortunately twice the price (but perhaps twice as nice)." Sorry Paul, we seemed to have got sidetracked discussing dbas. I really would like to still help if I can.
What's your current thinking?
Tim
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jazz99
Hi Paul,
I was just wondering if we hijacked your thread. We haven’t heard from you for awhile now. On your last post on 3/1/19 you stated: "I suppose one has to make a decision at some point, so will try to decide (after auditioning) between the SVS SB1000 and the JL Audio Dominion D110, which is unfortunately twice the price (but perhaps twice as nice)."
Sorry Paul, we seemed to have got sidetracked discussing dbas but I’d really like to still help if I can.
Any updates on your sub search? What’s your current thinking?
Tim
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dave_b:"
No such thing as perfect bass response...varies by venue! So, that being the case, one can relax and get 1 or 2 subs for their system and play around until your happy with the sound. Doesn’t need to be over engineered or killed with angst! Have fun, grab a brew and enjoy the tunes."
Hello dave_b,
I completely agree that there's no such thing as perfect bass response, especially in such a compromised space as a domestic room. I now consider the number of subs and their configurations more as available method options that can be measured, both subjectively and objectively, and ranked in their relative effectiveness in typical rooms.
I'm one who took your advice about four decades ago and got a decent passive sub with a 12" driver, and an Adcom GFA545 class AB amp to power it, in an attempt to attain better bass response, extension and impact in my room from an early system that lacked all 3.
It was around 1980 and I was trying to attain better bass response not only for music but also for my first home theater attempt and incorporating Dolby 5.1 surround sound audio into my system.
This is how and when my experience using a single sub in my system began. As I recall, it was exciting and fun to experiment with sub positions and settings for the first time. I was able to attain very good bass response at a single listening position for ht. For music, the bass was more prevalent and had more impact at my listening seat but clearly did not integrate well with the fast and smooth midrange/treble response of my planar-magnetic panel main speakers; I consistently perceived the bass as a bit lagging and disconnected.
Years later, I bought a self-amplified Klipsch sub with a 10" driver from a friend and experimented with using 2 subs running in both mono and stereo configurations. I had difficulty distinguishing a significant benefit with both subs along my front wall in a stereo configuration as compared to mono configuration. But I did notice the bass seemed faster, smoother and better integrated with my main speakers from my listening seat after I used the 'sub crawl' method to sequentially position each sub.
I finally concluded the bass sounded best to in my room with both running in mono, one along my front 16' wall about 4' away from the right corner and the other about mid-point along my left 23' wall.
I was convinced about a decade later by James Romeyn, and extensive related research on the subject, to purchase and home audition for a 4-week in-home trial period the Audio Kinesis Debra 4-sub distributed bass array system all powered by an included 1,000 watt class AB mono amp.
As some of you know I've already stated about 2 gazillion times and climbing, the Debra system has provided the best bass response in my room and system that I've ever experienced.
The bass is extremely natural, seemingly effortless, amazingly detailed and integrates seamlessly with my fast Magnepan 2.7QR panels. It's capable of accurately reproducing whatever type of bass the content calls for; rhythmic, solid, taut bass with natural leading edges and decays on music as well as sudden, dynamic bass with dramatic impact on ht and music.
I was originally contemplating just buying 2 high quality traditional self-amplified subs that were larger. But I rationalized that the Debra would be about the same price ($2,800) as 2 expensive subs and, based on several very positive pro reviews and the impressive published scientific results of how well the dba concept works, that I shouldn't pass up the chance to try it out at no cost except time and determine for myself how well this solution actually works.
Well, the results far exceeded my expectations. I now consider my system's bass as state of the art and honestly can't think of a single bass performance quality that needs improvement. Oh yeah, and this sota bass response is perceived throughout my entire 23x16x8 foot room including all 6 varied seating positions.
I now consider the bass quality of systems using 1, 2-3 and 4 subs as good, better, best. Why waste time messing around with 1-3 subs and having some 'fun' when you could just buy an A K 4-sub dba, or build your own custom dba and have a blast? You'll have the rest of your life to relax and enjoy it since you certainly won't, IMHO, be searching for a better bass system.
Tim
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Hello gormdane,
I generally agree with your statement that "most full-range speakers can benefit from adding a subwoofer (ideally two - one each for the L/R channels). You will definitely get increased bottom end, greater ambiance, and improved soundstage. The trick is blending them with your mains - you really don’t want to know they are there other than hearing the perceived benefits". I agree with using 2 subs if your goal is smoother bass response at your listening position but not if your goal is 'stereo bass'.
I believe advising "ideally two subs-one each for the L/R channels" is very misleading since it implies that positioning a sub beside each of the L/R main speakers will provide smoother, or even stereo, bass response. Two subs can provide smoother bass response at the listening position but the bass will be mono and it requires very specific positioning of each sub in the room that will likely not be a sub located next to each L/R speaker.
I read Jim Smith's book and watched his dvd on Getting Better Sound about 20 years ago. I think it's very useful for anyone assembling a home audio system for music or ht but would not recommend it for advice on achieving good in-room bass response. Perhaps he's updated his section on good bass and subwoofers since I read his book, but I remember him emphasizing the proper positioning of full-range speakers in relation to the listening position for smoothest bass response and making no mention of a distributed bass array system consisting of 4 subs at all.
In retrospect, he seemed to take a very traditional and conservative approach to achieving good in-room bass response that stressed obviating the need for any subs with high quality and properly positioned full-range speakers and completely ignored alternative approaches.
I think such a highly renowned 'good sound expert' should have been aware of critical scientific research and conclusions reached on the use of dbas about this time (20 years ago), the fallacy of true 'stereo bass' along with any other alternative methods of achieving good bass response via the use of 1 or more subs in a room and mentioned this in his book.
A shortcoming that was a shame for me in particular, since it took me another 15 plus years to discover the revolutionary effectiveness of dba systems thanks to James Romeyn and Duke Lejeune.
Tim
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Hello rauliruegas,
The bass will be mono because there's no such thing as true stereo bass below about 80 Hz and there are virtually no vinyl or cd recordings that have separate bass recorded for the L/R channels. The recording engineers sum the bass below a certain frequency and evenly distribute the combined bass on the L/R channels so it is located to the center when played back via a stereo system through a pair of speakers.
In my opinion the best sounding solution, if you're going to use 1 or more subs, is to run them in mono mode and position them at positions in the room that sounds the best to you (smoothest and most natural) at the listening position.
The major benefit of this approach is that the deep bass will be perceived as stereo (even though it's not recorded in stereo) from your listening position. This is a result of the higher frequency harmonics or overtones of the fundamental deep bass tone being recorded and played back through the L/R stereo speakers since they generally extend above the approximately 80 Hz frequency that the bass is typically summed in the L/R channels in mono.
These higher frequency harmonics/overtones give clues to our brains. Our amazing brains are able to process the non-directional inputted deep bass fundamental tones, along with the directional higher frequency harmonics/overtones or clues, determine that they are related and assign a specific room location the non-directional deep bass tone originated from.
This is generally referred to as a psycho acoustic effect but it is consistently perceived as sounding very real to us humans.
Tim
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Hello hornguys/Jim,
My mistake, I had open-heart surgery in 2008 and had a stroke immediately after. I'm much better now but my memory may have been damaged more than I realized. Given your info, I must have bought one of your initial print copies and read it while recuperating in 2009.
Funny, I'd swear it was closer to 20 than 10 years ago but I now know it has to be 10. Thank you for the correction and I apologize for my faulty memory.
I find it encouraging that you know Duke and have communicated with James. You stated "I do disagree with some of what they espouse, as they probably disagree with me". I'm curious as to whether this concerns in-room bass response and subs, care to elaborate?
It could be my faulty memory acting up again, but I still believe and wish your very good book contained more information on the best methods to integrate subwoofers into one's system. I now know it's a bit more complex achieving better bass sound in a room than better midrange and treble sound through personal experience and research.
I think your book would benefit from a more thorough discussion on getting better bass sound; aspects such as the difference between utilizing 1-4 subs, various sub positioning strategies for each quantity of subs, sub bass driver sizes, sealed versus ported subs, advantages of low pass filtering the main speakers versus running them full-range as well as the other bass system adjustments that enable seamless bass integration with the mains such as sub volume, crossover frequency, low-pass filter slope and sub phase settings.
Thank you for sharing your vast audio experience and knowledge for so many years. I think I speak for all members when I state that we'd definitely appreciate hearing your thoughts and opinions more frequently on this forum going forward on whatever subjects you choose to contribute.
Tim
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Hello rauliruegas,
"The information in the recording R2R (part of the overall recording process) comes in stereo way including bass range and is only when starting the LP cutting process when the low bass switched to mono due the severe limitations in the LP analog alternative."
True, the reel to reel analog master tape would include separate and unique L/R deep bass range information that would need to be summed to mono prior to being used for the LP cutting process, due to physical limitations of the LP format.
"Cd's comes with low bass signal in stereo not mono."
False, cds have traditionally had their low bass below a certain frequency summed in mono even though the cd format has no stereo bass limitations and the analog R2R master tape with true stereo bass could have been transferred directly.
This makes no sense to me, I've yet to hear a good explanation of why this was the accepted method among cd recording engineers and it seems no one's been able to name even a single cd that contains true stereo bass information. Can you name a cd, rauliruegas?
The good news is that, if these analog R2R master tapes still exist in good condition, they can simply be transferred to the even higher capacity 24 bit/96 Khz digital FLAC or WAV file format and be preserved virtually forever. Exact digital copies of the original analog masters could also be downloaded by consumers like us for a reasonable fee. Listening to exact copies of analog R2R masters, how great is that?
The bad news as I understand it, however, is that some download companies such as HD TRACKS sell downloads advertised as hi-rez that are nothing more than Redbook cds, with summed mono bass as a bonus, literally just transferred to a higher capacity digital format or bucket.
IT IS LITERALLY IMPOSSIBLE FOR THESE SUPPOSED HI-REZ DOWNLOADS TO SOUND EVEN AN IOTA BETTER THAN THE ORIGINAL REDBOOK CD SINCE IT'S JUST AN EXACT COPY OF THE ORIGINAL REDBOOK CD!
Sorry for yelling but this really gets my panties in a bunch. At best this is seriously false advertising and at worst may be legally fraudulent. In either case, I believe HD Tracks needs to explain themselves.
HD Tracks customers must be very disappointed with their downloads and wondering why they don't notice any quality improvements. Any HD Tracks customers care to explain their experiences?
Tim
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Hello rauliruegas,
You need to be more specific about my comments not making sense. I'm a bit biased but I think they make perfect sense.
The main point is whether you're aware of ANY cd containing discrete L/R channel deep bass information?
Careful with your tests, please don't disregard my comments about mono deep bass being perceived as stereo deep bass with the directional assistance of higher frequency harmonics/overtones being heard from the main speakers. This is a real psycho acoustic effect that I've experienced in my own system.
Thinking about this further, my thoughts are that, ultimately, it's best just to run any subs in one's system in mono. The reason being that the deep bass will be perceived as stereo deep bass regardless of whether the recorded content contains discrete L/R channel bass information or not. I know this is true with my ears/brain, with my bass system and in my room.
My mom always tells me I'm special but the truth is more likely that everybody's able to perceive mono bass as stereo bass with the assistance of additional directional information coming from the main speakers.
Tim
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Hello rauliruegas,
Okay, now I understand.
Thanks for the clarification and looking forward to your results.
Tim
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