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  • #31
    Re: How much SPL do you really need?

    Originally posted by Pallas View Post
    Interesting on the woofers. I didn't know Seas made an XLS competitor. Where's the crossover now? Perhaps the new woofers are forcing the crossover to the relatively small (Seas Excel 8") and unloaded midranges down too far? I could often see the poor little guys moving.
    I don't know the "history" of the L26, or if it was even available when ORION was first introduced . . . and it is not "inexpensive". The W/M crossover has been lowered by about 20Hz., more to acomodate the change from "H" frame to "W" than any deficiency in the driver, I suspect, and that change comes mostly to get the "force cancelling" mount . . . ORION 4 doesn't "rock", where the original ORION sometimes did. Beyond that I wouldn't discount "business" reasons as much as performance in accounting for the change, there are . . . benefits . . . that derive from an "all Seas" driver lineup.

    I haven't completed the 3.3 "upgrade" on mine yet, so I can't comment on whether it results in the "poor little guys" (they are Seas W22EX for those not "in the know") "moving" noticably more than they used to . . . but I'm pretty sure that they are up to it. I've never heard even a hint of problem with them at the higher crossover, certainly no compression or "rounding-off" of peaks. Using the recommended 60 Watt midrange amplifier the amp would clip before the driver exhibited any stress, and that clipping would be easy to test for, and audible. It doesn't happen at realistic listening levels . . . and a properly gain-staged system will limit upstream from the crossover/amp/driver anyway.

    I have heard quite a number of "high efficiency" loudspeakers in pro applications . . . everything has it's place. In my house I have no desire or need for the sound levels they can produce, so I have no reason to deal with, or endure, their deficiencies. Re. another commenter's posts about HT installations . . . if I were installing a "dedicated high-end HT" in a 20x40 sound deadened room I'd probably put three Econowaves (or some commercial equivalent) across the front wall . . . (and listen to music elsewhere . . .). As it is the 70" JVC HD-ILA sits neatly behind and between my ORION, and they (plus subwoofers) get as loud as I ever want when watching movies. Without "compression", I might add . . .
    "It suggests that there is something that is happening in the real system that is not quite captured in the models."

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    • #32
      Re: How much SPL do you really need?

      Originally posted by Deward Hastings View Post
      I don't know the "history" of the L26, or if it was even available when ORION was first introduced . . . and it is not "inexpensive".
      Not sure where that came from, but it's not that expensive, either. Though at four per speaker pair, it does seem to add ~$400 to the cost of the Orions compared to the old bass drivers. Not chump change, to be sure.

      Originally posted by Deward Hastings View Post
      The W/M crossover has been lowered by about 20Hz., more to acomodate the change from "H" frame to "W" than any deficiency in the driver, I suspect, and that change comes mostly to get the "force cancelling" mount . . .
      Interesting. I wonder if there will be an "Orion 4.1" that moves the xover back up a bit. The little Excel 8 seemed to be going awfully low for an unloaded driver at AXPONA.

      Originally posted by Deward Hastings View Post
      I can't comment on whether it results in the "poor little guys" (they are Seas W22EX for those not "in the know")
      Great car audio midbass, that little Excel...

      Originally posted by Deward Hastings View Post
      I've never heard even a hint of problem with them at the higher crossover, certainly no compression or "rounding-off" of peaks. Using the recommended 60 Watt midrange amplifier the amp would clip before the driver exhibited any stress, and that clipping would be easy to test for, and audible. It doesn't happen at realistic listening levels . . . and a properly gain-staged system will limit upstream from the crossover/amp/driver anyway.

      I have heard quite a number of "high efficiency" loudspeakers in pro applications . . . everything has it's place.
      In other words, you can't compare them to a set of high-efficiency speakers designed for high-fidelity in a small room. So you don't really have a leg to stand on here, now do you?

      Originally posted by Deward Hastings View Post
      As it is the 70" JVC HD-ILA sits neatly behind and between my ORION, and they (plus subwoofers) get as loud as I ever want when watching movies. Without "compression", I might add . . .
      With all that diffraction from having such a giant box between your speakers, no doubt it's hard to hear subtle dynamic details!

      Seriously, speakers of that caliber deserve better than to be subjected to a giant diffraction generator between them. Measure the speakers in room with and without the thing between them, and you'll see exactly what I mean. If anything, I'd expect an open-baffle to suffer even more from such diffraction than a monopole, let alone a good narrow directivity monopole!
      --
      "Based on my library and laboratory research, I have concluded, as have others, that the best measures of speaker quality are frequency response and dispersion pattern. I have not found any credible research showing that most of the differences we hear among loudspeakers cannot be explained by examining these two variables." -Alvin Foster, 22 BAS Speaker 2 (May, 1999)

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      • #33
        Re: How much SPL do you really need?

        Originally posted by Pallas View Post
        In other words, you can't compare them to a set of high-efficiency speakers designed for high-fidelity in a small room.
        Correct. I cannot compare directly to the null set.

        Originally posted by Pallas View Post
        With all that diffraction from having such a giant box between your speakers, no doubt it's hard to hear subtle dynamic details!
        Well . . . "all that diffraction" is in your imagination. Placing the "giant box" in and a bit behind the dipole null all but eliminates any "diffraction" problem . . . which would have no effect on "subtle dynamic details" in any case. If it were a problem I'd fix it . . . but it isn't.
        "It suggests that there is something that is happening in the real system that is not quite captured in the models."

        Comment


        • #34
          Re: How much SPL do you really need?

          Originally posted by Deward Hastings View Post
          Correct. I cannot compare directly to the null set.
          Are you seriously claiming that there are no high-efficiency speakers designed for high fidelity in a small room?

          Originally posted by Deward Hastings View Post
          which would have no effect on "subtle dynamic details" in any case.
          I agree. What I'm saying is that you've so lowered the potential resolution of your system by shoving a giantic angular box between your speakers, that perhaps you have other problems to address before comparing your speakers with ones designed along the lines that my listening experience has shown me I prefer.

          Not to say, of course, that one couldn't reasonably prefer something else. Whenever there is difference, one cannot necessarily predict preference. But one has to actually have experience to form a preference. You seem not to have the requisite experience to form a credible preference. Which may be how you wish to keep it, as going in a different direction would likely result in financial losses from selling your current gear. But don't pretend your position is based on anything other than blind path dependence.

          But seriously, measure your Orions with and without that hulk squatting between them. Also, note how much "fresher" your ears feel with the speakers properly set up, i.e. without that thing between them. Diffraction effects are a leading cause of listener fatigue.
          --
          "Based on my library and laboratory research, I have concluded, as have others, that the best measures of speaker quality are frequency response and dispersion pattern. I have not found any credible research showing that most of the differences we hear among loudspeakers cannot be explained by examining these two variables." -Alvin Foster, 22 BAS Speaker 2 (May, 1999)

          Comment


          • #35
            Re: How much SPL do you really need?

            Originally posted by Pallas View Post
            Are you seriously claiming that there are no high-efficiency speakers designed for high fidelity in a small room?



            I agree. What I'm saying is that you've so lowered the potential resolution of your system by shoving a giantic angular box between your speakers, that perhaps you have other problems to address before comparing your speakers with ones designed along the lines that my listening experience has shown me I prefer.

            Not to say, of course, that one couldn't reasonably prefer something else. Whenever there is difference, one cannot necessarily predict preference. But one has to actually have experience to form a preference. You seem not to have the requisite experience to form a credible preference. Which may be how you wish to keep it, as going in a different direction would likely result in financial losses from selling your current gear. But don't pretend your position is based on anything other than blind path dependence.

            But seriously, measure your Orions with and without that hulk squatting between them. Also, note how much "fresher" your ears feel with the speakers properly set up, i.e. without that thing between them. Diffraction effects are a leading cause of listener fatigue.
            You do realize, that to the side of a dipole speaker, radiation is greatly reduced. That's why Deward is saying that diffraction effects are minimal, because the radiation to cause diffraction is very low relative to the front/rear field.

            High efficiency speakers tend to be large, and thus, not suited to a small room.
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            • #36
              Re: How much SPL do you really need?

              You do realize, that to the side of a dipole speaker, radiation is greatly reduced. That's why Deward is saying that diffraction effects are minimal, because the radiation to cause diffraction is very low relative to the front/rear field.
              I do realize what he thinks he's saying. I'm saying he's wrong, because the null is relatively small, the giant reflective hulk is between and behind the speakers (emph. added), and he's ignoring the impact of back wave reflections. Arguably, on an open baffle such effects are more deleterious because backwave reflections that are already smearing the midrange just get worse as they reflect again and again.

              High efficiency speakers tend to be large, and thus, not suited to a small room.
              Not really. Consider something like the Danley Sound Labs SH-100. It's about 20" H by 20" W by 10" D, and 95dB/W/m. Even a GedLee Abbey 12a isn't a huge speaker, at 29" H by 15" W by 12" D, and is probably ~92dB/W/m. The best cone-dome speaker known to ,e, JBL's LSR6332, is 25.0" H by 15.5" W by 11.5" D and rated 93dB/W/m. (Interestingly, Harman uses those in their traveling listening room, not the big Revels.) In actual rooms, they can all present smaller than conventional cone-dome speakers because they have restricted directivity up high. That means they can be closer to the front wall without sonic penalty.

              What those speakers don't have is very extended bass. But who cares? They can still produce high SPL down low, because they have big drivers. And one can use the front wall for more LF reinforcement without the sonic penalties one incurs from wide-dispersion speakers put against the wall. Besides, the sonic benefits of distributed subwoofers are so well documented in the literature today that anyone who still persists in spouting "full range speaker" dogma just looks ignorant. So reasonably sized, efficient, controlled directivity, and comparatively bass shy is simply the smart way to do speakers in 2011.

              And in fact I would argue that the smaller the room, the narrower the pattern should be. Thus, the larger the speakers should be, to maintain pattern control down as low as possible.
              --
              "Based on my library and laboratory research, I have concluded, as have others, that the best measures of speaker quality are frequency response and dispersion pattern. I have not found any credible research showing that most of the differences we hear among loudspeakers cannot be explained by examining these two variables." -Alvin Foster, 22 BAS Speaker 2 (May, 1999)

              Comment


              • #37
                Re: How much SPL do you really need?

                On a set of really good speakers with adequate power, music doesn't "sound loud," or at any rate doesn't sound louder at high actual SPL than it does at low actual SPL.
                I've seen this concept mentioned before, and frankly, I think it is false. Is there any quality data to back this up???

                My understanding of "loudness" is that it depends on many variables (frequency, duration, spl, variability from one person to another, etc).
                I have no doubt that distortion can contribute to perceived loudness. I have experienced this for myself. So I concede that high distortion sound will sound louder at a given spl. But, to claim that there is no difference in perceived loudness between sounds of different spl with equivalent distortion seems ridiculous.

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                • #38
                  Re: How much SPL do you really need?

                  Originally posted by Pallas View Post
                  I do realize what he thinks he's saying. I'm saying he's wrong . . . and he's ignoring the impact of back wave reflections.
                  You've got your theory . . . and some totally ignorant speculation about what I'm "ignoring" . . . and I've got about 30 years experience with full range dipoles that says your theory is wrong. So do a lot of other people . . .

                  Originally posted by Pallas View Post
                  Not really. Consider something like the . . .
                  A bunch of HT horns (and I've already said I'd use Econowaves if I were making a big HT) that would probably sound their best flush mounted in the walls. Fine for movie sound tracks . . . not a real good choice for music.

                  Originally posted by Pallas View Post
                  And in fact I would argue that the smaller the room . . . the larger the speakers should be
                  That's . . . useful . . . :rolleyes:
                  "It suggests that there is something that is happening in the real system that is not quite captured in the models."

                  Comment


                  • #39
                    Re: How much SPL do you really need?

                    Originally posted by mtmpenn View Post
                    I've seen this ["sounds loud"] concept mentioned before, and frankly, I think it is false. Is there any quality data to back this up???
                    I don't know of any studies, but seriously, just go listen to some speakers!

                    Originally posted by mtmpenn View Post
                    I have no doubt that distortion can contribute to perceived loudness. I have experienced this for myself. So I concede that high distortion sound will sound louder at a given spl.
                    So we're in broad agreement, then.

                    Originally posted by mtmpenn View Post
                    But, to claim that there is no difference in perceived loudness between sounds of different spl with equivalent distortion seems ridiculous.
                    It is ridiculous. And not at all what I'm claiming. Indeed, I'm claiming the opposite. What I'm claiming is simply the increase in SPL is perceived differently as a result of...something. I don't know what the factor is, however. An relative increase of some order of distortion? Diffraction perception, which is known to vary in perceptibility with level? Simply the difference in small-signal performance and large signal performance?

                    But on really great speakers, instead of "sounding loud" the music just swells with increased level. One doesn't know how actually loud things are unless there's an external stimulus: trying to talk to the person next to you, not hearing your phone ring when the ringer's on full-blast and you can feel it vibrating in your pocket, something like that.


                    Which is why a good case can be made, IMO, that some people (namely, those who will instinctively take any system "to 11" for long periods of time) should, to protect their hearing, go for speakers that start to "sound loud" at dangerous levels, rather than more accurate ones.

                    Originally posted by Deward Hastings View Post
                    You've got your theory . . . and some totally ignorant speculation about what I'm "ignoring" . . . and I've got about 30 years experience with full range dipoles that says your theory is wrong.
                    Given that you've not mentioned anything about comparative measurements of the speakers with and without the hulk between them, let's just assume you're waving your hands here and moving on, OK?

                    As you concede, theory is with me here, so the onus is on the person staking a claim that's inconsistent with current theory to provide data to show that, in a given situation, the theory does not hold.

                    Originally posted by Deward Hastings View Post
                    A bunch of HT horns (and I've already said I'd use Econowaves if I were making a big HT) that would probably sound their best flush mounted in the walls.
                    You should really check things out before you go off making wild and incorrect assumptions. I intentionally posted three speakers (only two of which use horns, albeit modern horns without diffraction slots) from different worlds that could work in a system designed for music enjoyment. The first is a compact speaker designed primarily for (according to DSL's website) PA-type uses, but happens to have qualities that make it useful in small rooms as well. The second, on Dr. Geddes' website, does not list a potential usage, only (exemplary) measurements. The third is actually a three-way direct radiator (no reasonable person would call the small waveguide on the tweeter a "horn") marketed as a midfield studio monitor. Though Harman International uses it in their flagship demo rooms. Rather than the big Revels, which I at least find interesting.


                    (You may further note that there is no giant box between the front three speakers.)

                    Also, what's wrong with flush-mounting? So long as the walls around the speaker are clean, that's a great option if it's feasible in a given room. I think most would do well to translate William Cowan's configuration into their own rooms:


                    I've not heard that room, mind. But the execution is thorough and sound, as one can see from his measurements.


                    But someone into audio gear rather than music I can see how flush-mounted speakers can be distressing, though: nobody gets to see how much you spent on your precious gear!

                    Originally posted by Deward Hastings View Post
                    Fine for movie sound tracks . . . not a real good choice for music.
                    You obviously prefer the timbral and spatial colorations inherent in dipoles. Nothing wrong with that, of course. My preference is simply different. After having actually sought out and listened to every practical configuration under the sun (standard, quasi-omni, bipole, open baffle/dipole, cardoid, controlled directivity with separate waveguide, small point-source coax, large point-source coax, coax with horn jutting out from the polepiece, dynamic line source monopole and dipole, electrostat, and probably several I'm forgetting.) I've found that I personally gravitate to speakers that take the room out of the equation as much as possible, which means speakers with controlled, narrow directivity from the midrange up, cross-fired (axes cross ahead of the listening position) in fairly live rooms. With distributed subwoofers. Such systems, in my experience, measure cleaner at the listening position than others, but ultimately it's all about preference. Given that the two types of systems sound obviously different, one can reasonably prefer one or the other. Neither preference is "right," simply different. It's not like we're talking about amps/wires/digital sources here, where differences rarely exist and thus claiming a preference based on sound (as opposed to any other factor) is as a rule unreasonable.

                    Keep in mind that I'm only writing about speakers designed for the enjoyment of music. Cinema sound is not important to me.

                    Originally posted by Deward Hastings View Post
                    That's . . . useful . . . :rolleyes:
                    It is for people who aren't shackled by thirty years of path dependence, as you boast of being. However, I was imprecise. What I should have written is that the smaller the room, the more important narrow pattern control becomes, and the less important LF extension and efficiency become. Unfortunately, that tends to require wider speakers.
                    --
                    "Based on my library and laboratory research, I have concluded, as have others, that the best measures of speaker quality are frequency response and dispersion pattern. I have not found any credible research showing that most of the differences we hear among loudspeakers cannot be explained by examining these two variables." -Alvin Foster, 22 BAS Speaker 2 (May, 1999)

                    Comment


                    • #40
                      Re: How much SPL do you really need?

                      Originally posted by Pallas View Post
                      As you concede, theory is with me here,
                      Um . . . no. Everybody's got a "theory" (or two) . . . tested against reality your theory is wrong. That's all . . .

                      Originally posted by Pallas View Post
                      a compact speaker designed primarily for (according to DSL's website) PA-type uses,
                      Just a few posts ago you were dismissing experience with and perceptions of "high efficiency" pro speakers, and then here you turn around and offer one as an example ? ? ?

                      As for the rest of your "hand waving" . . . :p
                      "It suggests that there is something that is happening in the real system that is not quite captured in the models."

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                      • #41
                        Re: How much SPL do you really need?

                        I thought I would throw in one more aspect to this discussion that has been sort of touched on but not directly - loudspeakers are not linear devices. As you apply more power, there is more power compression. As you drive the cone farther away from small signal excursions, there will be more distortion from motor and compliance non-linearities. In short, if you want clean loud sounds, even if this is just for transients to cover your crest factor desires, than you should consider over designing your loudspeaker in terms of excursion capabilities and so on. For instance, I like to try and design for 110dB@1m SPL when the driver is reaching Xmax. There is no way I am going to listen to the system at that volume, but this gives me some peace of mind that it will be able to reproduce dynamics cleanly at my listening position, 10'+ away from the speakers.

                        I realize that the original question was about the SPL level for listening, but because of where this thread wandered off to, I thought I would add this comment to the mix. It seemed like the OP was attempting to get to some answer related to speaker design criteria, but maybe I was reading in to it too much.

                        -Charlie
                        Charlie's Audio Pages: http://audio.claub.net

                        Comment


                        • #42
                          Re: How much SPL do you really need?

                          Originally posted by Deward Hastings View Post
                          Just a few posts ago you were dismissing experience with and perceptions of "high efficiency" pro speakers, and then here you turn around and offer one as an example ? ? ?
                          Most PA speakers are bad sounding. A few are not.

                          Originally posted by charlielaub View Post
                          I thought I would throw in one more aspect to this discussion that has been sort of touched on but not directly - loudspeakers are not linear devices. As you apply more power, there is more power compression. *** In short, if you want clean loud sounds, even if this is just for transients to cover your crest factor desires, than you should consider over designing your loudspeaker in terms of excursion capabilities and so on.
                          I think we're in broad agreement, and I think this is restating what you meant more or less. But as you allude to with your first two sentences, how those levels are reached may be important, not just if those levels can be reached. Consider the following drivers complements with similar volume displacement (parameters largely taken from real-world drivers, though names have been deleted because they cloud rather than illuminate things):
                          2x 7" midwoofer, each one 12.5mm xmax, 84.7dB/W/m: 655cc total swept volume.
                          1x 12" midwoofer, 6mm xmax, 95dB/W/m: 655cc swept volume.

                          I believe the two will change sonic character in different ways with increasing level, despite having the same theoretical SPL limits, because of how they reach that SPL. The 2x7" complement requires both more power (and thus has more compression) and more throw (compliance, inductance, and other things vary over stroke, too) to reach those compared to the single 12.
                          Last edited by Pallas; 05-12-2011, 01:59 PM.
                          --
                          "Based on my library and laboratory research, I have concluded, as have others, that the best measures of speaker quality are frequency response and dispersion pattern. I have not found any credible research showing that most of the differences we hear among loudspeakers cannot be explained by examining these two variables." -Alvin Foster, 22 BAS Speaker 2 (May, 1999)

                          Comment


                          • #43
                            Re: How much SPL do you really need?

                            Originally posted by penngray View Post
                            Simply not true. There are standards that you can google.
                            Do you have a link that says 90dB for 30 minutes will damage hearing?? All my links and even work standards say 8 hours.
                            OSHA is famous for protecting some of the ears, some of the time. Work standards are a bare legal minimum.

                            As I pointed out before, 90dB measured how? The legally enforced standard least likely to damage your hearing, as opposed to protecting some of the people some of the time, is directive 2003/10/E. This table sums it up in a nutshell. Personally, I'd try to stay in the "providing protection is mandatory" category, but thats just me. 92db A-weighted for 30 minutes a day equivalent. So, yeah. But note the A.

                            Originally posted by penngray
                            Several facts.

                            1. A common distance in custom HT rooms is 15 feet.

                            2. Peaks in movies can be 25 to 30 dB.

                            3. If you are listening at 15 feet and you want clean peaks when listening at 75 dB you will need speakers that can do 115dB. Not only the speakers but the amps have to handle the peaks cleany.
                            Hate to nitpick, but two out of three are definitely not facts.

                            Listen, the very short version is that films are mixed in calibrated rooms and each speaker never sees more than 105dB. It can't, because the headroom isn't there. And it isn't there because that is insanely loud.

                            Buy an SPL meter. Set it to C-weighted, slow. Play pink noise out of one speaker and turn it up until it reads 85. See how long you want to stay in that room. That's reference level in a theater, and you get 20dB of headroom for peaks above that.

                            Now lets test your 90dbA. Set your meter to A-weighted, slow, and turn it up to 90dB. Now sit in that room for 8 hours, and let me know what you think of OSHA.

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                            • #44
                              Re: How much SPL do you really need?

                              Originally posted by spasticteapot View Post
                              I'm curious - how much SPL, regardless of frequency, do you think is required at the listener for a hi-fi experience? 90dB at your ears seems to be a general minimum for continuous listening, but what about high-power transients?
                              Hi-Fi... Opinions vary. There is a big difference beween a system most people find adequate for home audio and a sytem that is suitable for a mastering studio that is capable of maintaining very high quality audio during high SPL crests. I think its useful to look at the requirements for the latter.

                              For mastering, you can look toward both Dolby's and Bob Katz's current recomendations for digital mastering, which are very similar. And Katz will tell you his remain very similar Ioan Allen's, 1970's pre-digital era Dolby, recomendations for mastering on analog tape.

                              Those sources have recommended a mastering level for high quality audio that falls between 85_dB to 86_dB at -20_dBFS signal level at 1_kHz, summed with uncorrelated phase at the listening position. That is 82_dB to 83_dB at 1_kHz at -20_dBFS separately from each of a stereo pair at the listening position.

                              For mastering, Dolby recommends using loudspeakers capable operating within linear range at 3_dB headroom above 0_dBFS, and asssociated amplification capable of 3_dB clean headroom above that.

                              The level at 1 meter includes the SPL reducion over the propagation distance, -6_dB for each doubling of distance from a point source. For example you would need to add 12_dB for a 4 meter propgation distance to the 1_kHz radiatior. For most speakers, 1_kHz is radiating mostly into 2pi from the face of the baffle, so the room isn't going to provide much help at the recommended 1_kHz used in setting levels, can be lumped into the headroom IMO.

                              As for levels at other frequencies, flat in-room response is a good nominal target, though IMO some contour would be desirable to more closely match whatever contour was seemingly used in the mastering, likely not flat.

                              Going with the high side of that...
                              83_dB at 1_kHz at -20_dBFS at 4 meters distance from one loudspeaker is
                              83+20+12 = 115_dB at 1_kHz at 0_dBFS at 1 meter distance.
                              3_dB of headroom gets you to 118_dB at 1_kHz at one meter, separately from each of a stereo pair, operating within linear range (Xmax? Xlinear?), at half power for the amplifier headroom.

                              But again, most people are not willing to dedicate the resources needed for that extreme for the purposes of high quality home audio. As I recall, I think the Linkwitz Orion can provide ~105_dB of SPL at one meter, which is 13_db below the figures detailed above, and the Orion enjoys a reputation for prodiving good quality home audio on a wide spectrum of recorded material. I think the discrepancy in capability is because the music recordings that we buy, the worst of it suffering excessive dynamic compression, but the best of it still being compressed enough in the recording and mastering processes to allow good sounding playback on home audio systems that are neither capable of providing the clean SPL on crests that we would experience with the loudest of live symphony orchestra sound nor even the somewhat lower capacity to accomodate dynamic crest levels that are suggested for mastering high quality audio.

                              Regardless any of that, nominal listening level at home would have to be similar to that used in mastering, and both similar to that experienced listening to the symphony orchestra live, else there is a nonlinear distortion in loudness perception imposed across the frequency range, illustrated clearly in the ISO:226 equal loudness contours. And the change is not perceived the same as a change in propagation distance. So there really is an appropriate listening level where straying to far from that appropriate level begins to impose excessive nonlinear distortion in the perception of loudness across the range of frequencies. The higher levels mentioned above describe the loudspeaker's ability to accomodate the dynamics on crests without imposing distortion associated with excursion beyond the linear range.




                              The attached image below from a reprint of an article published in the February 2009 issue of The Hearing Review provides some info on live SPLs at listening positions in the audience and also among the musicians, the full article at this link. It is the peak SPLs that are of interest in avoiding mechanical clipping in loudspeakers, representing the high levels witnessed on brief crests in the music.


                              edit: I started writing this earlier and was distracted by work. When I got back to it, I didn't read the other comments before posting. I now see that Deward has already chimed in with info on the Orions which I think serve well here as an example of a domestic loudspeaker that seems to enjoy a generaly positive acceptance among those who report on listening to them.
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                              • #45
                                Re: How much SPL do you really need?

                                I hope I don't open up a bad can of worms, but... How do you guys who want to watch a movie at 75db, find 75db? All my source material sounds different and levels are all over the place.

                                I can use pink noise to match the main speakers to a sub from a listening position and set the sound to 75db, but if I stick in a movie or CD, at the same volume level, it may or may not be loud enough to play at the same level.

                                Do people really try and find the reference level when they watch a movie, or do they just stick it in, and play back at the level they want? Like me, and everyone else I know would do.

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