Why the fascination with subwoofers?


I have noticed many posts with questions about adding subwoofers to an audio system. Why the fascination with subwoofers? I guess I understand why any audiophile would want to hear more tight bass in their audio system, but why add a subwoofer to an existing audio system when they don’t always perform well, are costly, and are difficult to integrate with the many varied speakers offered. Additionally, why wouldn’t any audiophile first choose a speaker with a well designed bass driver designed, engineered and BUILT INTO that same cabinet? If anyone’s speakers were not giving enough tight bass, why wouldn’t that person sell those speakers and buy a pair that does have tight bass?
128x1282psyop
@noble100 -- 

I'm not a Bass-Head but I admit I enjoy the bass weight and power that viscerally involves your whole body in the music or ht. 

I can relate to that - certainly. For bass to be able to be enveloping, effortless and visceral are vital aspects for bass to simply be uninhibited. 

But I also believe in setting the crossover frequency as low as possible so the subs only engage when required for accuracy and not for an artificial general system bass boost.

An "artificial general system bass boost"? I don't see why this would be the necessary outcome of a higher cross-over between the mains and subs. One may have a wider frequency span to adjust bass level and overall response, but to me - using an 80Hz cross-over - the goal is the same compared to using a lower XO: for the overall integration to be smooth and seamless. 

Perhaps one of the issues of using a higher cross-over point, apart from it being potentially problematic using several subs scattered throughout the listening room, is the thought of using a high-pass filter over the main speakers. This is understandable, I've been there myself, but I can attest to the positive outcome using a quality digital XO over the mains, and that any detrimental effect on transparency with a proper unit is perceived as zilch. Some may bark at this and claim such a component will inevitably have its say on the sound, and they may be right, but to which degree and in what context? Using a quality digital XO over the mains and high-passing them at at least some 80Hz have a plethora of other advantages that can easily (more than) alleviate a theoretically negative effect a given component may have being added to the chain:

WIN # 1)  Since you are now NOT putting in 20 Hz - 80 Hz into the mains you are not using up the available LF cone movement with bass, so the LF cone in your mains is able to play its higher freqs (up to IT'S crossover point) much more cleanly. You get an apparent 6dB or more dynamic range. You can play your system LOUDER, and also with less compression distortion in the LF driver when you're having that Saturday night dance party and you're playing urban bass technopop at 110+ dB. Really.

WIN # 2)  Since you are not putting bass into that same driver you are not Doppler modulating everything between 80 and 600, or whatever the next crossover point is. This means cleaner mids. By far.

WIN #3)  You are not sucking current out of your main power amp at low frequencies, so there is more current reserve to play those highs louder...

WIN # 4)  Since the cones aren't moving as far at the low freqs the driver itself is not generating as much back EMF therefore the damping factor and all of its issues are greatly negated. And you don't need to run silver plated cold water pipes to your mains as speaker wires because there is less current draw by the speakers.

WIN # 5)  Freqs below 80 are now NOT causing transient intermodulation distortion with the higher freqs (and vice versa) in your power amp. Cleaner still.

http://www.soundoctor.com/whitepapers/subs.htm

I've also discovered that bass quality is vastly more important than bass quantity. A leaner presentation without much extension is preferable to me than lots of bass if that bass is thick, colored, and sluggish. If the bass isn’t well reproduced, I think most would agree we’d rather not hear it at all. The poor bass performance becomes a constant annoyance and a reminder that we’re listening to a reproduction. 

Agreed.

I've learned that realistic reproduction of the majority of the bottom octave (16Hz–32Hz) doesn't require large woofers in large enclosures, 4 subs with 10" woofers in relatively small enclosures are equally capable. 

Equally capable compared to what? There are many iterations of using only a pair of subs that involves 21" units (or bigger) and/or horn subs that would leave 4 spread out 10" direct radiating subs sounding close to malnourished. Would 4x10" be sufficient in many listening rooms to many listeners? I believe so, definitely, but others would disagree, and it's not necessarily for them being "bass heads" as such; what is "realistic" to you may not be the case with others and their setups. 

It's also true that a system’s bass presentation affects such seemingly unrelated aspects of the sound as midrange clarity and sound staging. Thickness in the mid bass reduces the midrange’s transparency. A cleaner mid bass not only makes the midrange sound more open, it also lets you hear more clearly into the extremely low frequencies. Moreover, extending a system’s bottom end has the odd effect of increasing soundstage depth and our overall sense of the recorded acoustic, even on music with minimal low-frequency energy.  

I concur, only to add that these advantages are potentially more pronounced using a high-pass filter over the main speakers, for reasons outlined above. 


However, I'd suggest choosing subs designed for musical accuracy, not home-theater fireworks. Some subs exist to produce the highest possible sound-pressure-level at the lowest possible frequency for playing back explosions in film soundtracks. Others are crafted by musically sensitive designers with high-end sensibilities. Be sure which kind you prefer and are selecting.


I don't find musical accuracy and "home-theater fireworks" to be mutually exclusive. Watching Blu-ray movies I simply notch up the bass level by some 1.25dB's (some may prefer even higher HT-boost bass level). This "amalgam" of proficiency with regards to both music reproduction and movie playback I find is no doubt rooted in the specific topology, namely horns (a pair of 15"-loaded tapped horns, in my case). Horn subs deliver the most musical bass I've ever heard in being more refined, smooth, enveloping, dynamic and effortless than any direct radiating solution I've heard. Horn subs vibrate the air in quite an omnipresent fashion that gives the bass a floating quality even that's rather unique.  No multi-use of direct radiating subs can achieve the same, period, and predominantly it has to do with how the cone couples to the air. Horn subs take up space, though, and 20 cubic feet for 20Hz reproduction may be a hindrance for many, if not most audiophiles. A shame, really..

Dear @phusis  : I concur with what you posted because those were and are my first hand experiences in my room/sysrtem for several years now.


Through those experiences I decided to in 2005 to post this thread ( I already postyed here but you don't read it, here again. ) that goes/coincide with your takes in the overall bass subject:

https://forum.audiogon.com/discussions/do-you-think-you-need-a-subwoofer/post?postid=310058#310058


Btw, the planar speakers develops too Inter Modulation Distortions and are benefitiated by those subs and the high-pass filter. No matters what.

The planar owners must test it before post it does not works because this is the idea they have. I posted the link og those Apogee The grand speakers that says it works and I have first hand experiences with the top of the line big and great sounding Soundlabs with and with out that high-pass XO and difference is for the better through that XO. But is up to flat speakers owners. 


Regards and enjoy the MUSIC NOT DISTORTIONS,
R.
Hello phusis,

     Your post brought up many good points and I believe most come down to your personal preferences being different from mine.
     I think we both agree that the 4-sub distributed bass array (DBA) concept is something that works incredibly well in virtually any room and with any set of main speakers, even fast speakers such as planar-magnetic and electrostatic panels.  I think this is bourn out by the fact that we both use them in our own systems.
     All DBA systems will provide accurate, detailed, smooth and natural bass that has an effortless quality to it.  But I consider the DBA concept to be an especially elegant bass system solution because of its scalability and flexibility that allows for customization based on personal preferences. 
     DBA's are scalable mainly by the choice of the 4 subs utilized.  I use the relatively small subs standard with the AK Debra DBA system that have a 1 sq ft footprint, are about 2 feet tall and contain 10" drivers.  Although this provides bass response in my room that's flat down to 20 Hz it's not quite able to reproduce the entire lowest octave of 16-32 Hz but this bass response has plenty of power, impact, extension and dynamics on music and ht for my preferences.  Others who may have a preference for more bass power, impact, dynamics and sufficient bass extension to reproduce the entire lowest octave have the option to choose subs that are as powerful, extended, expensive and large as they prefer or can talk their spouses into.
    DBA system's are flexible mainly by the choice of system settings such as the crossover frequency, whether the main speakers are run full-range or restricted and the overall bass system volume relative to the main  speakers.  I prefer setting the crossover as low as possible, typically in the 40-50 Hz range, because I run my main speakers full-range, they only have accurate bass extension down to  36 Hz, I find the bass sounds better integrated when the subs only engage when the content requires it and I perceive the bass as boosted overall when the crossover is set much higher.  
      You've stated you prefer setting your crossover at 80 Hz and using a high quality digital xover to restrict the bass output of your main speakers. This not only demonstrates the flexibility of DBA systems but allows other significant benefits as well that you detailed.  I understand your point about perceiving the bass in your system as still natural and well integrated even at your much higher 80 Hz crossover.  Perhaps it could be we just differ a bit in how we perceive moderately deep bass as it approaches  frequencies that we're able to discern where the bass is coming from.  But the DBA flexibility still applies since we're both just using the available DBA settings to attain the system performance and other benefits that we enjoy and prefer in our systems. 

      The overall DBA system volume relative to the volume of the main speakers volume is another important setting that allows significant flexibility.  I prefer a bass system volume that is slightly less than half volume on the sub amp which allows the deep bass to be independently powerful, detailed and dynamic while still integrating well with the mid-range and treble of the main speakers as the overall volume level is varied from soft to loud.  
     But like you, I'm not adverse to increasing the relative bass system volume on certain Blu-ray movies or even some music.  Just our personal preferences easily catered to by the flexibility of our DBA systems,right?

Tim
Dear @noble100 : """ All DBA systems will provide accurate, detailed, smooth and natural bass that has an effortless quality to it. """

as can do it non DBA subs system. As you said maybe a different way " to see things " but DBA is not the only or best option. Clearly is for you and other gentlemans but exist other very good alternatives to it.

Not only you but other audiophiles are running their passive main speakers in its full range way and I can’t understand yet why what @phusis and before him me posted here and in other related subs threads ( at least me. ) the main critical advantage when any one integrates two or more subs to his system using a high-pass filter that permits to put at minimum the main speakers IMD kind of distortions.

The rewards doing that with passive speakers is not some thing tiny, no it’s more significant perhaps that to have those additional low bass octaves. Of course that we can understand it only when we have that experience.

I posted in that linked thread that my main discovery when I integrated my subs to my system ( where my main speakers goes down to 16hz. ) was the overall " impact " that was developed by lowering the main speakers IMD kind of distortions. Yes I know your targets are different from pussin or mines but you must try it in some future time and if you test it then the XO point can be at around 80hz and subs wired in true stereo fashion.

I think that we can’t diminsh the IMD developed distortions by the main speakers no matters what if I was you at least I will try and if you don’t like it then always come back at the original status.

Normally the owners of planar type speakers are " against " to run the main speakers as a " satellite " one that is the " rigth " way to go ( for me. ) because that high-pass filter makes a paramount difference.

Yes, my high-pass filter is inside my 20.6s amplifiers where I don’t need to use any kind of external active/passive XO due that my amps are coupled by small caps.

Anyway is up to each one of us, only an opinion that can improve our daily MUSIC pleasure.

Regards and enjoy the MUSIC NOT DISTORTIONS,
R.
Dear @noble100  : I did not knew which is the crossover frequencies in your 2.7qr and now I find out:

Low-Pass 12dB/octave @ 650Hz

Band-Pass 6dB/octave @ 500Hz-950Hz


those " numbers "  makes me to tell you it's almost and " emergency " and your speakers are " shouting " for that high-pass filter ! !

Rigth now you have good bass and you can have an exceptional mid/high ranges in your system adding that high-pass filter.

IMHO it's a must that you do it because the IMD distortion levels is to high and in a very wide range up to over 900hz. It's a serious compromise to leave it that way.
A compromise is that you can have a better  quality " equilibrum " with your bass range if you can achieve better quality levels in the mid/high frequency ranges. As I said before is up to each one of us.

Btw:   you said that the CD's and other digital sources you own/use does not goes below 20hz. Maybe you are rigth but always exist a dude because your system does not have the ability to shows you if in reality goes only to 20hz or below it.

R.
rauliruegas:
"Dear @noble100 : """ All DBA systems will provide accurate, detailed, smooth and natural bass that has an effortless quality to it. """

as can do it non DBA subs system. As you said maybe a different way " to see things " but DBA is not the only or best option. Clearly is for you and other gentlemans but exist other very good alternatives to it."

Hello rauliruegas,

     Yes, it's definitely possible to attain very good bass response using 1 or 2 subs.  As we've discussed previously, this is a bit of a compromise since the 1 or 2 subs need to be precisely positioned in the room to optimize the bass response perceived at a single dedicated listening position.
      This specific sub positioning process for 1 or 2 subs restricts good bass response to the immediate vicinity of the dedicated listening seat and, by necessity, results in much poorer bass response at many other areas of the room.  However, some individuals require good bass response at more than just a single listening position and a 4-sub DBA system is an excellent method to achieve good bass response not only at the dedicated listening seat but also throughout the entire room.

rauliruegas: "Normally the owners of planar type speakers are " against " to run the main speakers as a " satellite " one that is the " right " way to go ( for me. ) because that high-pass filter makes a paramount difference."

     I completely agree with you that one of the major benefits of adding subs, and running the main speakers as satellites, is that it frees the main speakers and their amp from reproducing the bass frequencies which results in less speaker distortion and reduces the demands on the amp.
     In my system, I've tried both configurations of running my planar panel mains full-range and with my mains as satellites with their low frequencies filtered out by the sub amp supplied with the Audio Kinesis Debra DBA system,  This amp has a L/R high pass outputs for sending frequencies above the bass crossover setting to the main speakers amps.
     I thought my system sounded best with the main speakers running full-range. The mid-range and treble range sounded very similar to me with both configurations but I did notice the bass range sounded more detailed and more dynamic with my mains running full-range.  
     I do have some thoughts about why I didn't discern improvements in the mid-range/treble range using the 'satellite method' as expected and as you have in your system.  I'm uncertain of the quality level of the high pass filtering being done in the sub amp.  But since I was unable to discern any differences in the midrange/treble response range between full-range and the satellite methods, I can only conclude that the filtering quality level is not an issue.  
     Also, any sonic gains expected from the reduction on bass frequency amplification demands on the main speakers amps may not have been realized since these mono-block amps are not lacking in power ( 1,200 w into the speakers 4 ohm load).  Another possibility is the Magnepan 2.7QR main speakers I use as mains.  These are 3-way planar panels that have rather large bass sections which provide very high quality bass on their own but that lack deep bass impact.  Perhaps the improved bass response I noticed with running the mains full range is a result of the very high quality and articulate bass of my mains combined with the increased impact and dynamics provided by the AK Debra DBA system.
      I think both our systems are just practical proof that there's several options available for achieving high quality bass response using subs.

Tim
Dear @noble100 : """ All DBA systems will provide accurate, detailed, smooth and natural bass that has an effortless quality to it. """

as can do it non DBA subs system.
This statement is false. If you encounter a standing wave, it often cannot be fixed with only 2 subs. And it can't be fixed with room correction or room treatment.

Now if you **don't** encounter a standing wave then its all good. But in many rooms a standing wave is highly likely- unless the room is irregular in some way. But any rectangular room will have a standing wave which will be a different locations throughout the room depending on the frequency. In such cases while that bass might be good at the listening chair for certain pieces of music, it may not for others. This is a simple fact of physics.

With a distributed bass array this problem is solved.
Dear @noble100  : Yes, with two true self powered subs for one seat position. We don't need more for that target. The Harman white papers confirm it.

I think that even that we agree in some bass management subjects the reality is that we can't agree and not because " we can't " as is but because looking your streamlinen system your targets and mines are totally different.

I don't use my system for HT and two channels listening MUSIC. My system was and is developed exclusively for listen two channels MUSIC, nothing more. Music coming from digital and analog alternatives.

As I told you my main target is to stay " nearer/truer " to the recording and to achieve that target I need a very high resolution room/system that means very high quality performance of any single link in the overall audio system chain with true accuracy and the lowest any kind of distortions I can achieve.
Obviously that to achieve all these we have to take care for the minimum details where in HT no body cares and even in two channels system some audiophiles not cares either. 

I gave that little explanation due that you said that using the high-pass filter you was not aware of differences in the quality level performance in the mid/high frequency ranges in your system.
After looking your system I understand now why you been not aware about: your system has not the resolution need it for even that very wide frequency bass range in the Magnepans.

As a fact you are not trying to put all kind of distortions at its minimum you can and that's why you gave me an answer that THD in the quasi-subs you own was not so important when in reality is way important with true self powered subs in a only two channels system. Everything is important and with high priorities in a two channels room/system when we want to stay not so far aways of live MUSIC as normally we are. 
Mi reference to achieve my target is live MUSIC seated at nearfield position ( 2-3m. ) that's where the  recording microphones are positioned.

For me is really important and was one of the reasons I choosed my servo controled Velodyne's that check every second 16K times the woofer excursions to mantain at lower than 0.5%  the THD. Other than Velodyne I don't know other true subs where the manufacturer gives the THD in its products.
I think I already mentioned that the JL very well regarded subs measured through Stereophile review around 6% on THD other subs reknowed subs are worst that that and certainly far away from that Velodyne figure.

I totally understand your fascination for your 4 quasi-subs bass array because for that price is almost imposible to achieve what you like in your system.
The manufacturer design must had to make " serious " compromises to stay at that so low price for the complete bass 4 array.

Anyway, at the end you have what you and me were looking for and if both of us achieved our targets then this is the more important fact.


Regards and enjoy the MUSIC NOT DISTORTIONS,
R.


@atmasphere --

This statement is false. If you encounter a standing wave, it often cannot be fixed with only 2 subs. And it can't be fixed with room correction or room treatment.

Now if you **don't** encounter a standing wave then its all good. But in many rooms a standing wave is highly likely- unless the room is irregular in some way. But any rectangular room will have a standing wave which will be a different locations throughout the room depending on the frequency. In such cases while that bass might be good at the listening chair for certain pieces of music, it may not for others. This is a simple fact of physics.

With a distributed bass array this problem is solved. 

There's nothing categorically false with poster @rauliruegas statement; you CAN have bass that is accurate, detailed, smooth, natural and effortless with two subs, end of story. Both room correction and -treatment can do wonders here, I find, and can (and should) be used sparingly for a successful outcome. Honestly it's becoming trite hearing the constant babbling about what a pair of subs can't, and the double count can. We know by now - 4 subs can be a hoot, and they ease up on the need for PEQ, definitely not trivial. Moreover, all things being equal a double-up in sub count gives a theoretical 6dB's more headroom, and I can certainly vouch for the importance of that. 

You could however take a pair (or more) of bigger, more sensitive subs placed symmetrically to the main speakers, horn load them even, and have a different kind of awesome with other advantages. I know, size is banned in audiophilia, but the simply fact of physics, to use your own words, also has size as a main priority that numbers can't alleviate. Big subs in high numbers, however..

And what's the issue and argument made with smooth bass coverage over a wider listening (position) window? One sub is a narrow sweet-spot, two is wider and so forth, and while a single sub may boarder on the head-in-a-vise sweet-spot, two is definitely good for a pair of listeners to have decent coverage. I don't know about you guys or ladies, but mostly I tend to listen to my setup by myself (and if not I give the other listener the sweet-spot, usually placing myself on a chair behind and to the side of the listening sofa), and I don't need for bass to be swell in every goddamn place in the listening room; the listening position (with room for two, if need be) will do just fine, thanks. Actually this is mostly dictated by the main speakers; I would never listen seriously any other place than smack in the middle between the mains, but that's just me. 
atmasphere: Certainly you need to learn a little on the whole bass management subject.

Certainly is not false my statement that was confirmed by the Harman white papers in his great bass management scientific abstract and I said abstract because they do not try to sell us nothing but only sharing critical information. From those WP:


" Four subwoofer at the wall midpoints (configuration 11) was the best practical configuration in terms of MSV. Two subwoofers at opposing wall midpoints (configuration 6) was nearly as good and also offered stronger low-frequency support. Configurations with more than four subwoofers were not found to be advantageous, especially when cost is factored in. These results appear to be generalizable to reasonably dimensioned rectangular spaces [19] . ""

Things are that I have no single problem in my system with two true self powered subs at one seat position.

R.


from those WP:

""" However, through the use of multiple subwoofers the seat-to-seat variation in the frequency response can be reduced significantly, allowing subsequent equalization to be more effective. Three methods to reduce seat-to-seat variation are described, including a novel approach based on simple signal processing. The desired result in each case is to allow the system to be equalized over a seating area rather than just one seat. Results are shown for several listening rooms. """

In my case I only need one seat and I’m " in ".

and remember: Why the fascination with subwoofers? when you are not using it yet but like to post and you have the rigth to do it.

I can't go on due that you have some " lawyers " here that will come to .............? ? 
Dear @phusis  : In the overall subs subject problem with some people as atmasphere is just igonrance levels/low knowledge level even this person has no subs in his system, go figure.

As you and me Noble 100 confirms that we can have really good bass managment with two true subs. Noble likes 4 because he used as HT too.

As you I only need one seat position to listen MUSIC and the only seat position is in front-middle of the main speakers because is where belongs the mid/high frequency ranges that only has one and only position to enjoy it.

At least we have first hand experiences that attest our coincident statements .

The other issue in almost all the bass threads in this forum is that almost no one cares about quality of that low bass ( only cares to room evenly bass reproduction. ) and many just do not care about the critical importance of the bass below 20hz but as you said: " that's just me ".



R.
Hello atmosphere,

     Agreed.  
     Standing waves result in room bass modes which are perceived as bass exaggeration, attenuation or even cancellation at the specific points they occur at in the room.  These room bass modes resulting from standing waves also vary by frequency and typically exist in the bass frequencies up to about 350 Hz.  
     As I understand how the distributed bass array concept functions, the 4 subs distributed throughout the room actually are intended to create more bass standing waves and bass modes that are fairly well distributed throughout the entire room.  
     Once there's a good distribution of bass room modes existing in a given room, the principles of psycho-acoustics are then utilized by the DBA concept.  Humans are very poor at discerning the originating source of deep bass frequencies (below about 80-100 Hz) but very sensitive in discerning the pitch and the volume of these deep bass frequencies as well as any changes in pitch and volume.  Our brains process these multiple bass room modes (bass peaks and dips at various frequencies)  by summing and averaging them which results in a perceived smoothing effect to the bass.   
      Scientific research by Earl Geddes, Floyd O'Toole and others has proven that the more subs in a given room the more the effects of bass standing waves are reduced and the more the bass response is perceived as good(accurate, smooth and detailed). They realized there's a practical limit to the acceptable number of subs in a domestic room, however, and their data showed that some of the bass smoothing effect began with as few as 2 subs in a given room but there was a threshold reached with 4 subs in a given room which mitigated the effects of the vast majority of standing waves in the entire room, with each additional sub beyond 4 only providing smaller and marginal improvements. 
        This means that 4 subs will assure very good bass response at all bass frequencies throughout the entire room, including the chosen dedicated listening position.  2 subs cannot provide very good bass response throughout the entire room, only at a single dedicated listening position and this very good bass response cannot be assured at all frequencies and with all recordings. 

Tim 
       
you CAN have bass that is accurate, detailed, smooth, natural and effortless with two subs, end of story.
Sure. That is why I qualified my comment: 
**If** you encounter a standing wave, it often cannot be fixed with only 2 subs. And it can't be fixed with room correction or room treatment.


(emphasis added; ***IF***)
If you *don't* have troubles with a standing wave then one or two subs can give excellent response.

The bass in "other parts" of the room aren't important particularly unless you curl up in the corner for a panic attack or some sort of modern dance move. I have a sloping high ceiling in my listening room, with one side opening up to a kitchen/dining area and the other side having large windows far enough away to make "first" reflections irrelevant, especially with horns that put the soundstage in front of me. In this arrangement my 2 subs work perfectly relative to the sound at the point where it matters...my pointy little head.
wolf_garcia:
"The bass in "other parts" of the room aren't important particularly unless you curl up in the corner for a panic attack or some sort of modern dance move."
Hello wolf,

    I agree that good bass response throughout the entire room is not important for many but it is for some such as myself. No, I don't curl up in the corner from my panic attacks or windup there from my very creative
modern dance moves..... at least as far as you know.

    It's important for me because I have 6 seating positions spread around my 23x16 ft living room that I use for both music and ht. Only one seat is in the sweet spot, precisely between my main speakers and directly facing a 65" plasma hdtv wall mounted between them. I have my dipole panel speakers positioned about 4' away from the front wall for optimum freq. response and imaging at the sweet spot seat. This works great for music at this seat but, of course, the stereo imaging effect is compromised at the other 5 seating positions along the left and right walls although the bass response is excellent at all seats.
      But music still sounds very good from these 5 other positions and, since all 5 have a clear view of the hdtv, it works very well for ht, too. The 5.4 surround experience (5 speakers and 4 dba subs) is very good from all 6 seats in the room. The bass response is outstanding, equally deep, detailed, powerful and dynamic from all seats with still very good mid-range/treble surround sound response and perception at the 5 non-sweet spot seats.
       With the volume goosed a bit on Blu-ray movies, the impressive bass impact can normally be relied upon to have at least 1 family member or guest jumping out of their seat at least once during any action movie at a bass intensive scene.


Tim
Dear @noble100  : HT and stero MUSIC reproduction room/systems needs are different.

Maybe that's why you are the only audiophile I know that can't be aware of the difference  using a high-pass filter in the stereo music main speakers and with out that filter even the wider frequency range in those bass drivers. Not only that but you said you preffers with out the high-pass filter because better bass quality performance.

Seems to me that or you are overall bass " oriented/biased " or for a stereo MUSIC your room/system bass has poor quality levels. Something is not " functioning " for a stereo MUSIC/sound listening experiences because the differences with that wider bass range in the main speakers drivers are not " subtle ". Something is wrong or was wrong when you tested about, it's impossible not to be aware of those " huge " differences for the better using the filter.

I can't be sure what is happening down there other what you posted in this thread.

Regards and enjoy the MUSIC NOT DISTORTIONS,
R.
rauliruegas:
"Dear @noble100 : HT and stero MUSIC reproduction room/systems needs are different.

Maybe that’s why you are the only audiophile I know that can’t be aware of the difference using a high-pass filter in the stereo music main speakers and with out that filter even the wider frequency range in those bass drivers. Not only that but you said you preffers with out the high-pass filter because better bass quality performance."


Hello rauliruegas,

Why do you believe the reproduction requirements/needs of HT and stereo music are different?
I believe a single system that is able to reproduce the full 20-20,000 Hz frequency range accurately, with low distortion and proper dynamics is fully capable of reproducing both with high quality.
My combination stereo music and ht system is fully capable of reproducing the full range of audible frequencies with high accuracy, very low distortion and powerful dynamics and, therefore, performs with high overall quality for both stereo music and ht.
You also seem to have difficulty understanding why I didn’t notice a significant improvement in the performance of my Magnepan 2.7QRs main speakers when connected to the high pass filtered outputs on my sub amp rather than being run full range. I believe you need to understand the details of my system to understand why I prefer running my main speakers full range.
I built my system from the bass up because good bass response forms the solid foundation for most music and ht. Bass is also the most difficult portion of the frequency range to achieve high quality performance at in most home rooms due mainly to the extreme length of bass sound waves which are longer as the frequency decreases. For clarification, a 20 Hz deep bass full cycle soundwave is 56 feet long and a 20,000 Hz high treble full cycle soundwave is a fraction of an inch long.
The system solution I decided upon was to construct a separate high quality bass section for reproducing frequencies from 20-100 Hz, which is the frequency range of my 4 subs, and a separate high quality full range section for reproducing frequencies from 35-20,000 Hz, which is the frequency range of my main 2.7QR speakers, and blend the 2 sections together seamlessly by precise adjusting of the crossover frequency and relative volume settings of the bass section. I consider this system solution to have been a total success with the crossover set between 40 and 50 Hz and the sub amp relative volume set just under halfway at about 11 o’clock on the dial.
I’m not exactly sure why you notice such a big improvement in your system performance using hi-pass filtering while I don’t.
I use a crossover frequency of 40-50 Hz compared to your 80 Hz. Any sonic gains expected from the reduction on bass frequency amplification demands to above 40-50 Hz on my main speakers amps may not have been realized since my mono-block amps are not lacking in power with 1,200 watts into the speakers 4 ohm load, so there’s no lack of power from the bass to the treble. The sonic gains of your amps being relieved of bass amplification demands to above 80 Hz, however, seems to have been much better realized. Do you think more regular and reserve power being freed up for your speakers midrange and treble drivers could be the reason you notice improved performance in those frequencies?
Another possible explanation of why I don’t prefer using the hi-pass filters in my sub amp could be the Magnepan 2.7QR main speakers I use as mains. These are 3-way planar panels that have rather large 620 square inch bass sections which provide very high quality bass on their own but that lack deep bass impact and dynamics. Perhaps the improved bass response I noticed with running the mains full range is a result of the very high quality and articulate bass of my mains combined with the increased impact and dynamics provided by the AK Debra DBA system. I’m unsure of how well the bass quality of your ADS speakers run full range would combine with the increased impact and dynamics provided by your Velodyne subs. Perhaps you can try it sometime and find out.

Tim
Post removed 
Excerpt from the OP:
I guess I understand why any audiophile would want to hear more tight bass in their audio system, but why add a subwoofer to an existing audio system when they don’t always perform well, are costly, and are difficult to integrate with the many varied speakers offered. Additionally, why wouldn’t any audiophile first choose a speaker with a well designed bass driver designed, engineered and BUILT INTO that same cabinet? If anyone’s speakers were not giving enough tight bass, why wouldn’t that person sell those speakers and buy a pair that does have tight bass?

... but why add a subwoofer to an existing audio system when they don’t always perform well, are costly, and are difficult to integrate with the many varied speakers offered.
Almost always the objection--"poor performance, costly, and difficult to integrate."

"poor performance" When it comes to sub 100Hz frequencies, the powered subs outperform most "full range" speakers. 

If you check the response curves of most "full range" speakers, their frequency responses start dropping off at around 100 Hz. Sometimes you can compensate with good room reinforcement, but if you're on a wooden suspended floor, forget it.

"difficult to integrate..." Not if you use powered subs with the right controls. My two subs have controls for volume, crossover, and (most importantly for integration) phase. A 2-way 180 deg. toggle won't cut it. Mine have 0-180 deg. phase controls. The controls are continuous with no notches nore 2- or 3-position toggles. The volume integrates the subs' outputs with the mains, and the crossovers match the LF dropoff curves of the mains without a hump or dip where the subs pick up the lower frequency curve.

It takes me about 2-3 hours to integrate subs with my stereo, more likely 1-2 hours. For phase I use a mono recording to adjust each channel separately and make sure the channels' phase blends seamlessly with the mains.

For a final check I use the Stereophile test & demo CD, and listen to the bass frequency samples that drop from around 150-200 Hz on down to about 20 Hz. I generally get a linear dropoff down to around 36 Hz, which is a good match for my Magneplanar 1.7s, which are fantastic in the 80-20K hz range but missing in action below 80 Hz.

"...are costly,..." If you want full range reproduction, powered subs can be a stone cold bargain. Consider the true full range loudspeakers such as Wilson XLF and top line Magico. They are hundreds of thousands of dollars. Now consider a pair of KEF LS50s at $1300. Yeah, their LF limit is 80 Hz, but from that point on up to 28Khz they are Stereophile Class A loudspeakers, all for $1300. Add JL Audio Dominion D110 sub for another $1050 (or two for $2100) and you have a full range S-phile-rated Class A pair of speakers (with anechoic bass extension to 27 Hz) for $2450 to $3400, which is far, far less money than full range floorstanders that could match the KEFs in speed, image, linearity, clarity, and bass integration.

Remember that with full range speakers, the massive deep bass backwaves create a turbulent tempest in the enclosure's interior, interrupting the cone movements of the midranges and possibly the tweeters as well. Powered subs keep all that bass backwave drama in a tight box separated from the mains.
So from my perspective, quality powered subs increase performance, enhance clarity, make room placement easier, *AND* save money.

A lot of the cost of full-range floorstanding speakers goes to the herculanean efforts to keep the cabinet panels and braces from vibrating. Exhibit A: WIlson XLF or whatever has followed.

I use 4 subs but I have floor to ceiling linear arrays and two subs just won't make it. If you are clever and work with your room acoustics and you have a point source system which is just about all of you, 2 subs will work perfectly fine. In most normally sized houses I do not see the need for drivers over 12".  I think 12" is perfect. In addition to a properly designed driver the key to sub performance is a very heavy solid enclosure. Any vibration of the enclosure is distortion. If you put your hand on the enclosure at volume and you feel it buzzing away you have a problem. The best enclosures do not resonate at all and you do not have to do anything to them. If your enclosure vibrates the first thing to do is go to the local granite store and you can usually get cut offs for cheap. Just place an appropriately sized piece right on top of the sub. That can help tighten things up quite a bit. Also make sure the sub has 3 spiked feet not four. Three feet make a much better connection to the floor. No rocking. Subs have to be right up against a wall or in a corner. They are 3 to 9 db more efficient this way.
Some people are after All the response , not just down to what their neighbours are ok with. If i had two speakers that incorporated the subs involved they would weigh 250 pounds each . A four way system tri amped is far and few between and i dont think manufacturers are willing to sit on them hoping someone will buy them before some fancy pants gives them a thumbs down. Everything is a seasoned to taste affair . Pick your components and turn your obtainable mains into monsters for a much more realistic concert experience. Or bump them up a little bit in low listening levels to make the sound fuller .
One benefit of of more subs is the ability to run them all lower . Less buzzing . Less distortion . 
Post removed 
steakster,

     Subs in corners, since they couple to two walls, typically results in a 3 db+ bass boost.   It sounds like you're making the right moves, keeping your subs way from the corners and controlling the effects of a suspended floor, to keep the bass clean and accurate, detailed, smooth and natural.   


Enjoy,
 Tim
Hello brskie,

     I’d suggest going with the Treo and 1-4 moderately sized subs would definitely be the more versatile option when compared to a pair of Quatros with no subs. I’ve never compared the Treos to the Quatros by themselves but I’m still fairly certain that either’s overall performance would be improved with even just a pair of well positioned subs. I maintain this opinion even though I’m aware the Quatros have built in powered subs and claimed bass extension down to 24 Hz +/- 2 dB.
     The main issue, from my perspective, is that these are both floor standing tower speakers and that virtually every owner is going to position them in their rooms so that the optimum midrange/treble response and stereo imaging is attained at the designated listening seat.
     The bass drivers are just along for the ride, located in the room a matter of inches or feet directly below the midrange and treble drivers. The apparent assumption that this positioning will also provide optimal bass performance at the listening seat is highly unlikely bordering on fat chance and no way.  I believe it’s a distinct and very significant advantage to have independently positioned bass producing drivers in virtually any room and any system.
     I even suspect that a pair of Treos, combined with a $2,800 Audio Kinesis Swarm 4-sub distributed bass array(dba) system, would outperform a pair of Quatros without additional sub assistance. It’s also very possible a pair of Treos, combined with just a pair of good quality and well positioned subs (a used pair of Vandersteen 2wq subs for example), could outperform a pair of Quatros without additional sub assistance when judged from the designated listening seat.
     I should mention I highly respect the Quatros along with Vandersteen speakers in general and my intention is not to disparage them. It’s just that I know, through research and personal experience, the near sota bass response attainable with at least two and up to four good quality, well positioned and properly configured subs in virtually any room and system. I think a pair of Treos combined with a Swarm type bass system, at a combined price new of about $9,800, would be an excellent performer and a unique audio bargain.

Best wishes,
Tim

Hi Everyone,

     I just wanted to let you know I’ve just finished setting up my system with my new dspNexus crossover which operates 8 channels at 192K. Each channel has extremely high quality DACs and the DSP I was able to attain with my subs is like nothing I’ve ever seen. I’ve got the mains running full range and four subs measured with Room EQ Wizard and processed the results with Multi Sub Optimizer and entered the 12 biquads per channel generated into Audio Weaver which is completely customizable to any system design you have. The team at Danville Signal Processing has been awesome with their assistance. My stereo has never sounded better. The realism of the music is eerily real. This is a great addition for anyone wanting to take things to the ultimate level of signal processing with accurate powerful base. 

DSP Results

Filter Results

Thanks,

Steve

I hate subwoofers!!!  That's why I own true full range, floor standing loudspeakers.

@kennymacc but many people are limited by their wife or girlfriend to small speakers.  Lots of skinny floorstanding offerings too that are not true full range.  thus the demand.

Hi @kennymacc 

    Just curious, why don’t you like them? I have 20.1 Maggie’s which are “full range” but they can’t touch my system with my fully integrated subs. It’s breathtaking, visceral, and seamless. I will say that before I had four and used multi sub optimizer it was a challenge to try to integrate just two for me. I had room nodes so bad my Pass X-250 would draw so much current trying to play the subs “loud” enough that I’d blow the fuse, lol. You can’t overpower science. . . The advice here and the effort is well worth it to integrate subs into any system in my opinion, even if it is just to offset room issues. 
 

Thanks,

Steve 

hifidream.  I don't literally hate integrating subs, I just prefer not to.  Heck, one of the best systems I ever heard was at a High End Audio shop in San Francisco which was comprised of a pair of Magnepan 3.7i speakers with a pair of high quality subs.  This system just swept me off my feet.     

@soundsrealaudio Haha, love it.  
@kennymacc - Totally understandable, it’s a pain to integrate subs and if not done correctly can make things much worse than enhance the music. 

- Steve