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This was posted at Tweaker's Asylum by jmkochevar and I think it is
worthy of a repost here where it might get wider distribution.
After reading, do you recognize you know?
I don't know, I think it's perpetual.
I like to keep many systems and rotate things. It keeps it fresh.
The article is good. It points out many situations I have considered or even felt. Though some are just silly but then again I really don't have the money to really play. yet
Taping speaker location - I don't do that, measuring tape works just as well.
As for the great (or not so much) advice by Klaus R. below... If reading books and technical papers leads one to become unscientific junk (AKA "audio DBT") apologist, and is used to justify one's own inability/unwillingness to hear differences between electronics, cables etc. - then thanks but no thanks. I suspect plugging ears with fresh bananas (dried might work, too) will help to achieve the same result, with much less time and effort wasted.
Jeff Dorgay had a couple of comments that interested me. One was "you can enjoy music on an iPod Nano, a million dollar system, or anywhere in between," and the other was "finally have the system I want." In other words, opposed to point #1 in the unease article, there can be an end point to assembling a system.
Reviewer Art Dudley, writing for Hi-Fi Heretic, wrote, "the purpose of a hi-fi is to play your records with an acceptable degree of fidelity, and thus bring music into your home." I became a fan of Linn in the mid-'80's, particularly due to their emphasis on listening for musical values rather than hi-fi artifacts and the acknowledgement that different people will have differing levels of musical expectation from their systems. Living with a system that doesn't meet your expectations won't let you get full value out of your music collection, but if a modest system allows you to thoroughly enjoy your records, then spending more is a waste of money.
My local dealer, through a series of in-store and in-home demonstrations, helped me determine what level of playback equipment it would take to satisfy my expectations. Then he outlined a purchasing plan that let me get a system into my home immediately and provided for cost-effective trade-ins to let me build my system over time with minimal loss. It took me three years, but I ended up with a system that made me happy for almost 20 years (when components began to fail from age and use). There's no need for audiophile unease when you've been able to hear in advance what it takes to satisfy you.
But nervosa I don't have, thank heaven!
Knowledge is the remedy. Read textbooks and/or technical/scientific papers about audio-related issues in physics, acoustics, room acoustics, psychoacoustics, musical instrument acoustics, sensory evaluation and other disciplines I don't think of at the moment.
Having acquired that knowledge, the next time a "designer who has single-handedly unearthed new laws of physics" wants to tell you that tiny metal bowls operate by "conversion of the room's low frequencies into high frequencies to cancel unwanted resonances", you will say, well, of course, frequency transformation, that's the trick, could have guessed it myself, now please leave me alone, I've got better things to do than listening to a quack telling fairy tales.
I doubt if you'll find many people that have them all. Or am I wrong? I can certainly identify with some of them in my own audio life, although I am also into denial.
I've avoided cheap-skateitis by experience, but I don't have all that much money or the room to go too far in the hi-end price direction.
"What did the Romans ever do for us?"
"Unease"? Yes, I think I know that feeling. Sometimes I have myself convinced that I am not living in a state of unease. But inevitably, one or more audiophiles stop by to annoy and to listen and my fragile stance begins to topple. The system begins to sound worse (or, not as good as before). I find that I can't wait for their neurotic asses to head back home again so that my system can relax and start sounding great again.
Really the best synopsis of the personal side of audiophilenervosia.
Somehow, I've managed to avoid all that. And when audiophiles hear my (currently more modest than it's ever been) system, they go "wow." As do non-audiophiles.
So -- my question is -- are too many audiophiles worrying about *the wrong thing*? Such as tweaks that make sonic differences so subtle that their very existence is controversial?
Focus too much on a tiny difference in imaging or a bit of grain, at the expense of the things that really do matter?
I think this is because when other people are present, there is now a direct acoustic reference that often makes the system sound "electronic" by comparison.............
"1. You will live with a persistent sense that all is not quite well, that you could do better, and that your system is always in need of something."
This is why the live reference, attending live concerts, is paramount. Because it often makes the difference in knowing what that "something" actually is.
"2. In an attempt to compensate for your unease you will develop a highly cynical reaction to reviewers who you will come to believe are at best delusional and at worst corrupt, on the payroll of manufacturers who provide them with audio goodies and more."
Although I do have such cynicism myself, for me it's because I've too often tried the raved products, and ended up disappointed. It's more of a case of "Fool me once, shame on you..... Fool me twice..... "
"3. A further ambivalence is invariably induced by the way audio products are priced. You have every reason to doubt the sanity of a world where a pair of interconnect cables can cost more than a car, and where glib reviewers speak of windows being opened, blacks being blacker, and highs being cleaner as a result. Difficult as you find it to admit, you secretly want to try these in your own system to determine if they actually might do something, which you secretly fear is so."
This was my case, until Item 2 took over..........
"5. You will start to listen to music you never really cared for in the past. Your spouse will become suspicious that your rock and serious instrumental tendencies have given way to smoky voiced chanteuses with, heaven help you, backing bands of players you hardly recognize."
This was almost never the case with me, but this comment raises another issue I was not overly aware of- I did know a few audiophiles who often bought certain recordings to best demonstrate the system, even though the music itself was.... uhhhhhh.... blah............ (Some people classify Diana Krall as falling into this musical category, but I don't. I actually enjoy her music.)
"6) To convince yourself that you are sensible, you will have one product in your rig that is 'killer' for the price."
I cannot speak for others, but having extra $$$ in the bank is a big deal for me. And the more "killer" items for the price in the system, the better.
"7) In an attempt to appear cost-sensitive, you will dabble in DIY. This could take many forms, but your new-found obsession with affordable paper-in-oil capacitors and high-quality resistors will serve as a shield against claims that you have become a nutter."
I only go to DIY if the alternative IMO is overpriced. Too many non-DIY options, however.
Whether or not people here think I'm a "nutter", I don't really care.......
"9. You have become blase about double-blind reviewing. You wish reviewers would do it but you can’t bring yourself to try at home."
Funny...... I try it at home, but wouldn't put much stock in a reviewer doing it..........
"10. Your home will become a temple to your religion. Cables will be dressed, risers bought, pucks placed on tops and speaker positions taped to the floor so you can always move them an inch or two around during a private listening service, safe in the knowledge that your little 'undo' trick will work."
My "temple" looks more like the repair bays of an auto shop than a "boutique" audio store......... And all my cables rest messily on the carpet............
The problem is that the sound field is different on different seats in the same venue, as has been shown my measurements:
Meyer, “Directivity of the bowed stringed instruments and its effect on orchestral sound in concert halls”, J. of the Acoustical Society of America 1972, No. 6 (pt 2), p.1994
Takatsu, “Acoustical design and measurement of a circular hall, improving a spatial factor at each seat”, J. of Sound and Vibration 2000, p.263
This fact makes the live reference a moving target. Further, you don't know where the mikes are placed during the recording of e.g. a symphony. Add the fact that loudspeakers radiate very differently as compared to musical instruments. I for one, in view of the above, have put the idea of using live concerts as reference to rest.
“The problem is that the sound field is different on different seats in the same venue, as has been shown my measurements:”
It’s not so much the “sound field” that is of benefit from the live reference, but training the listener on timbral and dynamic characteristics of the real thing. A definitive reference that helps one migrate toward that sonic ideal with his home sound reproduction.
Or in other words, if one hears an oboe on a recording, how would he know whether it sounded like how it was supposed to if he had never heard an oboe in the flesh?
“This fact makes the live reference a moving target.”
Maybe in regard to soundstage and perspective, but IMO there is a common tonal quality that I think provides an invaluable reference for seeking more lifelike sound from a home audio system.
“Further, you don't know where the mikes are placed during the recording of e.g. a symphony. Add the fact that loudspeakers radiate very differently as compared to musical instruments. I for one, in view of the above, have put the idea of using live concerts as reference to rest.”
This is all relative. My contention is if one does not attend live concerts, how would he know whether the sound he’s hearing from an audio system is “right?”
Prior to attending live concerts, I had pre-conceived notions of how live music probably sounded like, which after actual experience, turned out to be *far* off base. (For example, I thought live orchestral music was much louder than what it actually was. And I never thought live rock music could sound clean to where aside from the electric guitars, everything sounded “acoustical”, even when amplified.) And had I never attended a live concert, I would have tailored the sound of my system toward those pre-conceived notions, rather than what was experienced. And I believe the end result would have been a vastly-inferior sonic presentation.
> It’s not so much the “sound field” that is of benefit from the live reference, but training the listener on timbral and dynamic characteristics of the real thing. A definitive reference that helps one migrate toward that sonic ideal with his home sound reproduction.>
Meyer shows frequency response measured at different locations in the hall for celli and first and second violins. Takatsu shows IACC (interaural cross-correlation coefficient) at various location in the hall.
The former relates to timbre, the latter to soundstage.
It would appear that also parameters such as clarity (C80) and lateral energy fraction are affected.
> Or in other words, if one hears an oboe on a recording, how would he know whether it sounded like how it was supposed to if he had never heard an oboe in the flesh?>
Even if you know how the real instrument sounds, the recorded sound reproduced via loudspeakers will sound different because of the very different radiation behaviour:
 Caussé et al., “Perceptual evaluation of a programmable radiation pattern loudspeaker simulating a real instrument”, 127th Meeting of the Acoustical Society of America 1994
 Caussé et al., Radiation of musical instruments and improvement of the sound diffusion techniques for synthesized, recorded or amplified sounds”, ICMC Proceedings 1995, p.359
 Misdariis et al., “Perceptual effects of radiation control with a multi-loudspeaker device”, Acoustics ’08, Paris, France
 Otondo et al., “Perceived influence of changes in musical instrument directivity representation”, Proceedings of the Stockholm Music Acoustics Conference, 6.-9. August 2003 (SMAC 03), Stockholm, Sweden
Once you realize these fundamental shortcomings of 2-channel stereo and the fundamental shortcomings of the usefulness of live concert hall experience and sound of musical instruments as reference, you realize that one should go to concerts for the pleasure of attending the concert rather than using the concert to train one's ears. YMMV, as usual.
"Meyer shows frequency response measured at different locations in the hall for celli and first and second violins. Takatsu shows IACC (interaural cross-correlation coefficient) at various location in the hall."
These kinds of measurements do not relate to timbre, etc. They relate to objective physical properties, not subjective perceptions which are the result of extensive processing by the brain. The human hearing system is not a measurement device. It correctly perceives timbre so that the type of object creating a sound can be accurately recognized under a wide variety of acoustic conditions. This ability has obvious evolutionary benefits, e.g. recognizing food, mates, and threats.
Reproduced sound will not sound different if the recording/playback is tonally flat and undistorted and the correct acoustic environment presented. If the acoustic environment is warped, then the brain will make an automatic compensation and one of the ways this will manifest is that the tonal quality will sound incorrect. If the instruments fit comfortably in a typical listening room, there will be no great problem in reproducing them accurately with first rate equipment given an appropriate recording.
If one wants to produce and reproduce recordings that sound like live concerts one must go to concerts and lots of them. One has to become familiar with many different venues, seating locations, and ensembles and how these interact acoustically. If all one wants to do is babel about how it is impossible to reproduce the live concert experience, than none of this effort is needed. Success will never be achieved by looking at a bunch of measurements. Measurements are useful only when equipment is on a design bench or repair shop.
"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar
> > Meyer shows frequency response measured at different locations in the hall for celli and first and second violins. Takatsu shows IACC (interaural cross-correlation coefficient) at various location in the hall. < <
> These kinds of measurements do not relate to timbre, etc. <
“Timbre is that attribute of auditory sensation in terms of which a listener can judge that two sounds similarly presented and having the same loudness and pitch are dissimilar” (American National Standards Association, New York, 1960).
The response curves at the different locations show differences of up to 5 dB, if you had two loudspeakers having two of these different curves as on-axis response you would not doubt for a second that they will sound different.
IACC relates to spaciousness, hence to soundstage.
> It [human hearing system ] correctly perceives timbre so that the type of object creating a sound can be accurately recognized under a wide variety of acoustic conditions. <
My daughter has a new flute, and I still have mine which is about 40 years old. You’d immediately recognize each of the two as flute, you’d also note immediately that they sound different. In the above mentioned paper Meyer addresses different seating arrangements: “ So the sound of the first violins is brilliant and very vigorous, while the sound of the second violins is a little dark and poor.” “The difference in timbre between the first and second violins (in the European seating arrangement) may be advantageous in passages where the same phrase must be be played by both groups alternatively.” No doubt you recognize both groups as violins, yet they sound different.
Meyer further elaborates: “ The greatest difference between the two groups (first and second violins) is measured by the microphone near the first violins, because the masking of the second violins by the musicians of the first violins is strongest here. The first violins are relatively loud here, especially in the lower frequency range, where they have no directivity. The higher-frequency sound does not reach this place in the angular range of preferred sound radiation, nor by a reflection from the ceiling, so the spectrum at this place has quite a different character than at other places in the hall.”
> Reproduced sound will not sound different if the recording/playback is tonally flat and undistorted and the correct acoustic environment presented. <
It must and will sound different because many musical instruments radiate different portions of their operating range into different directions, whereas loudspeakers don’t make such directional distinction, and because human hearing is directional, meaning that it makes a spectral difference whether the same frequencies come from the front, or from the sides, above or from behind. Searchers at French IRCAM (Institute for research and coordination of acoustics and music) have found that there is a perceptual difference between an instrument and its reproduction via loudspeakers and that when the directivity of the instrument is simulated by a dodecahedron loudspeaker arrangement, the perceptual gap is closed. This is the reason why directivity behaviour of instruments is analyzed, as to include the correct behaviour in acoustic modeling of performance venues (auralization).
> If all one wants to do is babel about how it is impossible to reproduce the live concert experience, than none of this effort is needed. Success will never be achieved by looking at a bunch of measurements. Measurements are useful only when equipment is on a design bench or repair shop. <
Without science and measurements you would not be able to hear a single note of your favorite music in your home, unless of course you were rich and had Karajan and Wiener Philharmonics come to your home and perform. If you reject science and measurements you should do that also when you GP uses both for diagnosis when you’re seriously ill, or when your audiologist wants to install the hearing aid with frequency response tailored to your particular impairment. If you think live concerts are useful as sonic reference for judging audio gear, be my guest. I no longer do.
> The response curves at the different locations show differences of up to 5 dB, if you had two loudspeakers having two of these different curves as on-axis response you would not doubt for a second that they will sound different.
Yes, but as Toole points out, the brain is remarkably good at deconvolving the contributions of the room and the original source. Comb filtering of a signal fed to a loudspeaker doesn't sound at all like comb filtering from natural reflections. The brain seems to integrate multiple arrivals to evaluate timbre, and to use the comb filtering to judge the nature of the acoustic space and position of the source instead. In fact, reflections seem to increase the ear's sensitivity to resonances in the source, by IIRC more than 10 dB.
So, in practice, frequency response distortions in a loudspeaker will be heard as such, whereas frequency response distortions introduced by a room may not be, depending on their nature.
Also, arguably, there are factors in the perception of sound in a concert hall that are invariant with respect to the sort of response variation to which you refer. If there weren't, we wouldn't be able to tell immediately whether we were listening to live or reproduced music. Arguably, some loudspeakers do a better job of reproducing the cues that suggest that we are in a concert hall. OK, knock out the "arguably" since some loudspeakers clearly do. So while we can't create "you are there" realism, we can get part of the way there.
> > The response curves at the different locations show differences of up to 5 dB, if you had two loudspeakers having two of these different curves as on-axis response you would not doubt for a second that they will sound different. < <
> Yes, but as Toole points out, the brain is remarkably good at deconvolving the contributions of the room and the original source. <
The point I wanted to make is that the sound at different parts of the concert hall is different, so there is no such thing as a live concert hall reference sound. If you read those parts of Meyer's, "Acoustics and the performance of music" (Verlag Das Musikinstrument 1978) that relate to the sound field at different part of the hall, with reference to the different instrument sections, it becomes quite clear from text and measurements (frequency response, octave level models, sonagrams, octave level analyses) that there are perceptible differences. The reference is hence a moving target.
Sure, but wouldn't the most accurate loudspeaker then be the one that reproduces the perspective on the recording? Which in most good recordings is an orchestra perspective, actually more like the perspective from an imaginary balcony over the front of the stage.
In my book the reference, in the sense of faithfulness to the original, is indeed the recording, not the live event. But whatever your reference is, the technical goals for loudspeakers should be clear: flat response, correct time alignment, low distortion, live-like SPL possible.
How are orchestras recorded? Close mike for every instrument, one mike for each instrument section, one or more mikes at different positions in the audience, what? Is the final mix representative of a particular seat in the hall?
It varies, from a single stereo pair flown above the front of the orchestra to individual mics for the instrument sections and soloists. While it's possible to screw anything up, in general, the simpler the mic technique, the better and more natural the recording.
You can't put conventional microphones where the audience would be, it doesn't sound right. The microphone doesn't "hear" what the ear does.
So in the first case the mike would capture the sound similar to the sound at the conductor's place? No one in the audience knows how it sounds at the conductor's position, and worse, no one in the audience knows how it sounds at a position above the front of the orchestra.
And in the second case the result is determined by what knobs the sound engineer turns and how he turns them, being similar to no position in the hall at all? No one knows how it sounds at this virtual position.
So what's the use of taking live concert as reference when no place in the audience is close to what the recording technique delivers?
I think you're making it out to be more difficult than it is. On a good pair of speakers in a reasonable acoustic, you'll hear pretty much what the microphone records. If the instrument is recorded from 2" away, it will sound like it's coming from the plane of the speakers. If it's recorded from 30' away, it will sound like it's coming from, if not 30', then 20', as it would in real life, since the brain tends to misjudged distance.
For a clear example of this effect, listen to the cow bell recordings on the Stereophile test disks. You can hear the distance of the cow bell as it moves from the front to the back of the stage. Different microphone techniques are used and while they produce different perspectives, it's a matter of precise location.
In practice, naturally mike recordings do a fairly good job of putting the orchestra on a simply miked recording where it should be -- at a distance from the listener, And they maintain, approximately, overall balance and timbre. The speakers aren't reproducing the sound from below, but from the front, and this reduces though it doesn't entirely eliminate the effect of the unusual microphone perspective.
In my experience, multi-miked recordings are less successful at producing an illusion of reality. They rarely sound natural, either in tonal balance or spatiality.
Sure, nothing can create a completely convincing illusion, particularly in the case of two channel stereo since two channels can't produce the sense of envelopment one hears in a concert hall. But the best recordings, played on the best speakers, have an uncanny ability to transport the listener into a different space.
I'd like to complement you on your ability to stay on topic and keep your posts both useful and reasonable. I strive to do as well but often fail :)
In spite of the previous paragraph I'd like to offer a slightly different experience:
I have an amazing number of well recorded surround SACDs which give a much more realistic (in the sense of being there) experience than this thread might lead one to believe. (Don't get me wrong I also have the a lot of ping-pong MC recordings and completely artificial recordings: some fun, some not.) To me it obviously more realistic to hear the orchestra clearly in front of you while at the same time hearing applause all around you... I know it sound like being there because I have listened to a lot of live performances as well as participating in bands, choirs, etc.
In my case I simply have well engineered equipment and minimal processing: no time alignment, no room correction, no diversion of bass to a sub. I just put four speakers up at equal distance from the sweet spot on as big of a circle as would fit in my room. There is no issue of soundstage depth or width, you are just there...
Thanks, I've been in so many Internet food fights over the years that I go out of my way now to keep things reasonable.
Which, however, isn't necessary here because I agree with you 100%. Two channel stereo can be very impressive, but there's no way it can transport you into the concert hall. At best, it's like peering through a window.
Also, as J. Gordon Holt used to point out, you can't get the tonal balance right on all material with two channel stereo. Flat response works well for small ensembles, but you need a 2-4 dB downward slope for orchestral material.
I seriously envy you your SACD collection! Multichannel is on my list, but I have so much to do just to reconstitute my two-channel setup that it's going to be a while before I can swing it. Maybe when I get my permanent speakers -- I've been using a pair of MMG's as temporary speakers since I can't fit my old Tympanis in my new room, and I'm thinking that I may end up using the MMG's for surrounds, if they fit.
Record playback is it's own art form, and recorded music is a thing distinct from (though obviously related to) live musical performance in a natural setting. All I have to do is listen and this fact becomes obvious to me. And while I came to this conclusion by listening (not by reading about it), I do not consider myself to be unscientific. But I will say that the gap between live sound and recorded sound played back through two loudspeakers seems to close as the musical event portrayed becomes simpler and/or smaller in size. Orchestral-sized events are the worst "live reference" one could possibly choose if one wants to fine tune one's system, in the hope that our loudspeakers will one day sound like live music. And while I am not rich enough to own (or even audition) the finest and most expensive loudspeaker systems in the world, I doubt that the very best loudspeakers are essentially better than the more affordable ones at blurring the distinction between "live" and "recorded" sound. The best loudspeakers might distort the recording less than the cheaper ones will, but they can never compete with or replace live music. Loudspeaker playback can sound real enough to suspend disbelief at times, but for the most part it is it's own strange thing.
> But I will say that the gap between live sound and recorded sound played back through two loudspeakers seems to close as the musical event portrayed becomes simpler and/or smaller in size. Orchestral-sized events are the worst "live reference" one could possibly choose if one wants to fine tune one's system, in the hope that our loudspeakers will one day sound like live music. <
I dunno. Some loudspeakers are clearly better at reproducing large ensemble works than others. Such as large line sources. And anything that can play loud, deep, and clean, with a uniform on-axis and polar response. Sure, we can't completely reproduce the concert hall experience, particularly with two-channel stereo, but we can produce a remarkable sense of being transported into another and larger acoustical space, one in which the walls of the listening room seem to melt away.
I think it was Earl Geddes who said that when the performance venue has about the same size and acoustic characteristics as the playback room then there might be a chance that reproduced music sounds like live.
> I doubt that the very best loudspeakers are essentially better than the more affordable ones... <
At blurring the distinction between "live" and "recorded" sound or otherwise. Loudspeakers have different radiation behaviour as compared to musical instruments so the perceptual gap will remain open, regardless of price.
As for the question if the very best loudspeaker are better than affordable ones, the answer depends on who you ask! Floyd Toole has obtained objective criteria for subjective loudspeaker quality. He said (some 5 years ago or so) that loudspeakers meeting these criteria can be made for something like $800/pair, you'd need to spend more for deeper bass. If I look at high-end loudspeakers in any price range, many of them perform poorly, according to these criteria.
We all know from experience that loudspeaker playback doesn't sound like the real thing, and science simply gives us some possible explanations.
The problem with Toole's theory is that AFAIK there aren't any $800 loudspeakers that sound as real as the best ones. Or if there are, I wish someone would let me know, so I can buy them. I don't see how there could be, because AFAIK the technology to make a state-of-the-art loudspeaker at that price doesn't exist.
Toole has tried to correlate objective measurements with subjective listener preference. He found that a particular behaviour of amplitude response (on and off-axis) is preferred in blind listening tests. What he says is that there is no need to spend big money in order to obtain this preferred behaviour, hence the price figures indicated.
What is state of the art in loudspeaker design? In Toole's book its flat response on-axis and smooth behaviour off-axis. To that add a clean waterfall plot and correct time alignment. That whole package possibly cannot be made for $800, especially if on top of that you want high SPL with low distortion.
That's exactly the problem I have. As far as I know, it isn't possible to make a loudspeaker that covers the whole audio range, has smooth on-axis response and good dispersion, and plays cleanly at a level that's adequate to reproduce all performances of un-amplified acoustical instruments at that price. Also, while Toole's criteria are good ones insofar as they go (although as I think he himself points out, it's an open question whether time alignment is necessary to the reproduction of music as opposed to test signals), I don't think they're the only criteria that affect loudspeaker performance. For example, state-of-the-art imaging and soundstage depth are difficult to achieve: arguably only a few esoteric line sources do it, or come close, without compromising maximum output. Similarly, there are issues of non-linear distortion, diaphragm breakup, and room interactions. In the absence of acoustical room treatment, dipoles and cardioids seem to have certain advantages. The upshot is that state-of-the-art reproduction seems to remain the province of large, expensive, and esoteric devices -- ribbons, line sources, large electrostatics, and dynamics that use exotic cone and cabinet materials and construction and servo woofer control. What's more, there doesn't seem to be a loudspeaker, no matter how elaborate or refined, that's state-of-the-art in every respect.
Not at that price range, no. But you don't need to pay astronomical prices either. In my opinion the speakers of the link below come close to the ideal. They use waveguides and DSP, no magic ingredients.
Time alignment: whilst not absolutely necessary, it makes a difference, even to the tin ear that I am :-)
"State-of-the-art imaging", what exactly is that and how do you know that the speakers are delivering those particular goods? What is the reference when judging imaging?
Soundstage depth: this would relate to distance perception in rooms. Nielsen in AES paper 3069 references some of the relevant literature. His introductory comments are quite interesting: "Sound reproduced through a normal set of stereo loudspeakers or a pair of headphones often lacks the impression of depth. This may be due to improper recreation of the oroginal sound field at the listener's ear. However, it may also be because the perception of depth by the hearing is not as good as we expect it to be. A reproduction cannot be better than the reality."
State-of-the-art reproduction: it would appear that only wave field synthesis is capable of recreating the original sound field, but that's a technology I'm not at all familiar with and anyway, there seems to be a problem in terms of home user acceptance.
Blumlein refers to the reproduction of depth in his original stereo patent, and I've seen a stereophonic demonstration film he made in the 30's in which the speaker's distance from the microphone is reproduced to spectacular effect. That affect won't occur to any significant degree with a monophonic recording. So while I think it's probably the future of sound reproduction, wave field synthesis isn't necessary to create a sense of depth in the stereo sweet spot, beyond the crude approximations of stereophony, anyway (MS stereo is really first order WFT with a single sample).
Room reflections seem necessary for this. In fact, according to Toole, first-order Ambisonics in an anechoic chamber didn't provide any sense of front-back localization at all! The same is true of headphone reproduction of conventional stereo recordings, which also lacks any contribution from the HRTF. That being the case, it's not surprising that it doesn't reproduce front-back perspective. That can be introduced in headphone listening with head tracking and real-time room and HRTF emulation -- see the latest issue of Stereophile for an interesting example.
To the best of my knowledge, very little is known about the psychoacoustical basis of depth perception. Toole's book, for example, essentially says "We have no idea." The reproduction of depth has something to do with recorded ambiance and listening room reflections, and it seems to be best reproduced by loudspeakers with uniform polar frequency and, according to one source, phase response.
AFAIK, to reproduce depth, two things are required: recorded reflections, and the ability to reproduce it in the listening room at an angular separation from the loudspeakers. Headphones and anechoic chambers don't satisfy these criteria. Neither does a loudspeaker with non-uniform frequency or phase response -- the issue here is apparently that the brain must be able to relate the reflections to the original source to interpret them as reflections or, perhaps, that spectral distortions introduced by the reproducer or room interfere with the brain's ability to localize the sound and gauge the acoustic on the basis of comb filtering and the HRTF.
The speakers in your link measure beautifully, and I'm all in favor of the use of DSP in loudspeakers. IMO, the high end industry is hopelessly stick-in-the-mud when it comes to the application of new technology. But, and it's a big but, I don't think a handful of measurements can completely characterize the audible performance of a speaker. The measurements aren't comprehensive enough and don't entirely reflect behavior in an actual listening room, and even if they were and they did, our understanding of psychoacoustics is too primitive to correlate the measurements completely with what we hear.
"I think it was Earl Geddes who said that when the performance venue has about the same size and acoustic characteristics as the playback room then there might be a chance that reproduced music sounds like live."
Exactly. It works great with one or two instruments in a large living room with full range speakers that have very flat on axis and power response The fine tuning required adjusts balances the remaining errors to a certain extent, e.g. by making minute changes in microphone position and aiming one can balance things off to the necessary tolerance.
If one moves about in the listening room one gets a different response from the live instrument. Once the differences between live and recording are down below this threshold then there won't be significant differences between live and recorded. Indeed, that may have been part of the "trick" when I did my piano experiments, since the reproduced piano was about 8 feet to the right of the real piano and along a wall, not in the corner. So of course it sounded slightly different, but so would the actual instrument if it had been moved. One needs to reach a threshold where the willing suspension of belief can take place. If one is overly obsessive one will never reach this point. However, if one has this kind of personality it is likely that one finds most activities frustrating and unsatisfactory and the solution for such a miserable life is not to be found in equipment, technology or other material possessions.
It goes without saying that the designers of the microphones and speakers (and other equipment) used science and measurement in their development and manufacturing process. However, science and engineering can only go so far and that is the point where the art of recording and reproducing music begins.
"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar
The way I see it, different types of loudspeakers specialize in different types of radiation patterns and they exist in order to cater to the personalized preferences of different types of listeners. There may be loudspeaker designs that qualify as "best overall", but the "jack of all trades, master of none" ideal may not appeal to everyone. Certain types of loudspeakers seem to capture the radiation patterns, dynamics, and timbres of certain types of instruments better than other loudspeakers do. If you like to listen to those types of instruments then you are free to specialize. And of course, certain loudspeaker designs are more expensive to produce than others are. Your choice of "favorite loudspeaker" might depend on what you consider to be objective criteria or it might depend on the kind of music you like to listen to... and, how much you want to pay! More expensive loudspeakers are definitely required if we want the deepest and most accurate bass, regardless of the topology. But I think many of us (consciously or unconsciously) accept the fact that as we optimize our systems for certain aspects of playback (or even for "best overall" level of playback), we simultaneously sacrifice playback capabilities in certain ways.
Radiation patterns of loudspeakers and musical instruments have absolutely nothing in common. A picture says more than 1000 words, they say, so I have prepared an overview (Word file, for the time being in German) of patterns of different instruments, taken from literature I was able to locate. Feel free to drop me a mail off-board for a copy.
As Toole has found it's not so much the type of pattern that matters as how well the response curves behave. Good behaviour is not a question of money, but of good engineering. Geddes speakers are an example.
Absolutely nothing? Or, is it a question of degree? No loudspeaker mimics the radiation patterns of musical instruments exactly but certain loudspeakers would seem to come closer than others in some instances, and sometimes that edge in similarity is what tips the scale in that speakers favor in those instances. The large radiating surfaces and dipole dispersion patterns of my old Magnepan 1.6 speakers had nothing to do with how realistic piano music sounded when I used them for this purpose? Are you saying that in-room frequency response was the only reason that piano music sounded so lifelike with these loudspeakers? I guess it's possible that frequency response is the only thing that matters in every case, but somehow I find that hard to believe.
I don't think that there's any evidence that frequency response is the only thing that matters. And a lot of evidence that while it's extremely important, it isn't.
"I for one, in view of the above, have put the idea of using live concerts as reference to rest."
It is not necessary to produce an illusion that corresponds to a particular location in a particular concert hall. Actually, the sound at a fixed location changes according to the audience, and that has proven to be a great problem in recording in some empty concert halls. (Recording in full concert halls presents other obvious problems.) One appreciates this after doing sufficient time in a variety of concert halls from multiple seating positions and different types and sizes of musical ensembles. If one has this experience, then one can recognize that reproduced sound is realistic. As with the live concerts, it is necessary to employ a large number (dozens) of reference recordings and become familiar with their impact.
If one hopes that scientific measurements will somehow resolve these difficulties, forget it. The recording and reproduction of music is more art than science.
"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar
I find that if you have at least twenty friends over the sound improves dramatically as all those bodies soak up sound. Organic live random kinetic acoustic treatment rules!
it's not a joke. it's true. it can happen.
twenty people means twenty more handphones in the near proximity.
that got to do some havok with the system's sonic purity.
also, an alarm clock will change a system's sound. imagine what twenty wrist watches will do.
I'm actually serious about that, though....
Ha ha, I fell into that trap for a while, then I realized that some of my albums sounded completely fine to me while others sucked. The ones that sucked... the loudest ones. In fact, the better my system got, the worse they were sounding. "Where the heck is this crackle coming from? Is something wrong with my speakers?" Nope, it was just clipping distortion. So I sold my heavily compressed cds (except the odd ones where I REALLY liked the music) and have drastically reduced my new music purchases.
Conclusion: My system is just fine, the Loudness War is the problem.
"Conclusion: My system is just fine, the Loudness War is the problem."
Hopefully the bastards perpetrating this nonsense will soon find themselves looking for careers outside the music business.
"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar
I know quite a number of people like that. I was almost one of them, until I realized one day that I was actually enjoying music less while it was in competition with the sound. I eventually settled on a system and promptly forgot about tweaking and upgrading, and my enjoyment of the music came back with a vengeance.
Quote from kerr: "... I eventually settled on a system and promptly forgot about tweaking and upgrading and my enjoyment of music came back with a vengeance."
Congrats, my friend. I think you have achieved a level of audio wisdom that freed you from the audiophile madness. I had a similar experience and now enjoy the music and my system (which has no audio component newer than ten years old) more than I ever did in those "myth of Sisyphus" days of the never ending search for audio nirvana.
> I think you have achieved a level of audio wisdom that freed you from the audiophile madness <
But once an OCD, always an OCD. I used to spend obscene amounts of money on audio gear. Now I spend obscene amounts of money on music software! :)
I play the piano and have a baby grand downstairs. The thought that a stereo system is going to closely reproduce the sound of a fine piano is laughable on its face. So it's a question of setting and accepting limits and enjoying the music. I have a couple more component upgrades planned and then I'm done.
After all, Beethoven is way more interesting than my power amp.
"I play the piano and have a baby grand downstairs. The thought that a stereo system is going to closely reproduce the sound of a fine piano is laughable on its face."
No problem. Done with recording gear purchased for $500 in mid 70's, and played back on a $1600 amp and $4500 speakers purchased c. 1990. Piano was a Steinway B (7 foot). Key thing was to have a dry recording (little reverb) and play it back in the room in which the recording was made. The speakers have to be full range, i.e. flat down to sub 30 Hz. The power capability needs to equal the sonic output of the piano, with perhaps 6 dB additional headroom. For best results it was necessary to tweak the speaker position so the size of the piano image is realistic.
You can find two such recordings from my website.
"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar
I don't believe you. Kenzo's new thread bears directly on this topic so hopefully an interesting discussion will result.
This is not a difficult demonstration. It has been done many times. It was done publicly in the 1960's. Acoustic Research sponsored a live vs. recorded demonstration involving the Fine Arts Quartet, which I heard in Payne Hall at Harvard University.
When I did it, the speakers and the piano were not in the same location, as I wasn't about to move the heavy piano about on the carpet. So the location of the piano and the location of the speakers were not exactly the same, hence it was possible to tell a difference between the two by the directionality. However, at a normal listening distance (20 feet) in the back of the room this was of little effect and the room was sufficiently reverberant as to cover up for these differences. The key thing to recognize is that the equipment was not attempting to reproduce the ambiance of the original room. It did not have to. That was provided because the recording was made with minimal reverberation (the microphones were just inside the opened lid, and then played back in the same room as the live instrument.) It was necessary to get the tonal balance correct. This was done by adjusting the microphone positions and tweaking the speaker aiming. It was also necessary to get the levels well matched and the polarity correct.
There was some tape hiss from the two track 7.5 ips recording. (It was necessary to record with very conservative levels, otherwise tape saturation would have introduced audible distortion, hence the hiss. As it turned out in the back of the room there was room noise that drowned out the hiss. Incidentally, it was not possible to achieve the desired effect with a Nak CR-7 cassette deck. If Dolby was used it was not transparent to the dynamics of the instrument. If Dolby was disabled the piano sound was accurately reproduced with lots of hiss at low recording level, but if the recording level was increased to make the hiss inaudible then tape saturation distortion destroyed the effect. (In the AR demonstrations they avoided a problem by continuously playing the tape during the live portions so the tape his would not be a give-away.)
One conclusion that I reached was that room acoustics are the critical factor. The room and its effects are vastly more important than any other component of a good record-playback system. Same room comparisons side-step this problem by canceling out room effects.
One thing to keep in mind: Even with this degree of accuracy, which I would say is "good enough for all practical purposes," listening to recorded music is not the same as listening to live music. The musical performance and intent differs on each live event, while a recording is always the same. To me as a music lover, this is vastly more important than any minute differences in sound quality between live and recorded music.
"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar
" Once this was all Black Plasma and Imagination." -Michael McClure
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