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#1
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Mind Stretchers
"Gary Eickmeier" wrote in message
... OK, I have been sufficiently worked over for now. I thank you all - or both - for some great discussion. You have read what I said, and that is all I can ask. NOW, assuming I am all washed up, that my statements that there is no stereo theory even at this late date in audio history is wrong, I sit at your feet as a student. How does stereo work? Strictly speaking Stereo over speakers doesn't work because it can't work. It's just like a car with 110% thermodynamic efficiency. It is an acceptable illusion or at least an illusion that many find acceptable. |
#2
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Mind Stretchers
"Arny Krueger" wrote in message
... Strictly speaking Stereo over speakers doesn't work because it can't work. It's just like a car with 110% thermodynamic efficiency. It is an acceptable illusion or at least an illusion that many find acceptable. Hi Arn - For the record (so to speak) - when I use the term "stereo" I am using it as shorthand for any and all loudspeaker based auditory perspective systems. This would include 3 channel, DD 5.1 surround sound, or any number of speakers placed around a room to try and reconstruct a sound field that mimics the original. I realize that to some, "stereo" means strictly two channel, but that is not what I mean. But if I use "surround" or "multichannel" in all discussions, people will think I am limiting the discussion to more than two channels, which I am not. Stereo can work with two or more speakers and the general principles apply to all of these. I hope that most of you are listening in surround sound to all recordings, even two channel. If so, you are at least partially agreeing with me on the reconstruction principle. If not, I've got my work cut out for me.... Gary Eickmeier |
#3
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Mind Stretchers
On Mon, 28 May 2012 11:13:04 -0700, Gary Eickmeier wrote
(in article ): "Arny Krueger" wrote in message ... Strictly speaking Stereo over speakers doesn't work because it can't work. It's just like a car with 110% thermodynamic efficiency. It is an acceptable illusion or at least an illusion that many find acceptable. Hi Arn - For the record (so to speak) - when I use the term "stereo" I am using it as shorthand for any and all loudspeaker based auditory perspective systems. This would include 3 channel, DD 5.1 surround sound, or any number of speakers placed around a room to try and reconstruct a sound field that mimics the original. I realize that to some, "stereo" means strictly two channel, but that is not what I mean. But if I use "surround" or "multichannel" in all discussions, people will think I am limiting the discussion to more than two channels, which I am not. Stereo can work with two or more speakers and the general principles apply to all of these. I hope that most of you are listening in surround sound to all recordings, even two channel. If so, you are at least partially agreeing with me on the reconstruction principle. If not, I've got my work cut out for me.... Gary Eickmeier Frankly, I find that the recording industry has a hard enough time doing two channel stereo correctly, much less four channels, or five or seven.... Now for movies where the extra channels have explosions and other sound effects pan-potted to them, it's fine, but I have yet to hear a music surround recording where I thought that the surround was any more than a gimmick. |
#4
Posted to rec.audio.high-end
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Mind Stretchers
Gary Eickmeier wrote:
For the record (so to speak) - when I use the term "stereo" I am using it as shorthand for any and all loudspeaker based auditory perspective systems. This would include 3 channel, DD 5.1 surround sound, or any number of speakers placed around a room to try and reconstruct a sound field that mimics the original. I realize that to some, "stereo" means strictly two channel, but that is not what I mean. But if I use "surround" or "multichannel" in all discussions, people will think I am limiting the discussion to more than two channels, which I am not. Stereo can work with two or more speakers and the general principles apply to all of these. Mr. Eickmeier, you have a lonn history of taking a term, redefining it for the purposes of some agenda, without letting anyone else know about your surreptitious redefinition, and then proceeding to argue from that point. For the record, "surround sound" was NEVER designed as a means of recreating the original sound field. Things like 5.1 surround and the like were developed as effects systems used in conjunction with video and the like. James Jophnston has elsewhere described how completely innappropriate surrtound-sound systems are for recreating sound fields. Perhaps you might want to research the subject before you hold forth on it. As to the "definition" of stereo sound, you may well like to redefinf it however you like, but you should note that there's an 80 jump on your claim to the definition, and should you disagree, you might want to take it up with the kind folks at Bell Labs. I hope that most of you are listening in surround sound to all recordings, even two channel. If so, you are at least partially agreeing with me on the reconstruction principle. If not, I've got my work cut out for me.... Yes, among other things, you have a LOT of reading up to do, not the least of which is on fundamental definitions. -- +--------------------------------+ + Dick Pierce | + Professional Audio Development | +--------------------------------+ |
#5
Posted to rec.audio.high-end
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Mind Stretchers
On Tue, 29 May 2012 03:30:00 -0700, Dick Pierce wrote
(in article ): snip As to the "definition" of stereo sound, you may well like to redefinf it however you like, but you should note that there's an 80 jump on your claim to the definition, and should you disagree, you might want to take it up with the kind folks at Bell Labs. Now here, you and I agree. Bell Labs defined stereo for the ages back in the early 1930's as I have mentioned at least once in this thread. Mr. Eickmeier's attempt to redefine it is fraught with problems, to say the least. |
#6
Posted to rec.audio.high-end
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Mind Stretchers
"Dick Pierce" wrote in message
... Mr. Eickmeier, you have a lonn history of taking a term, redefining it for the purposes of some agenda, without letting anyone else know about your surreptitious redefinition, and then proceeding to argue from that point. Mr. Pierce, what a treat! Thank you for taking the time to share your extensive knowledge. For the record, "surround sound" was NEVER designed as a means of recreating the original sound field. Things like 5.1 surround and the like were developed as effects systems used in conjunction with video and the like. James Jophnston has elsewhere described how completely innappropriate surrtound-sound systems are for recreating sound fields. Perhaps you might want to research the subject before you hold forth on it. Hey, what a great idea! But, indeed, I have been reading voraciously about all this for over 30 years now! But I didn't stumble across a statement like that - do you have any references or quotes to help us out here?. As to the "definition" of stereo sound, you may well like to redefinf it however you like, but you should note that there's an 80 jump on your claim to the definition, and should you disagree, you might want to take it up with the kind folks at Bell Labs. Gosh, it sure seems like you know something there that I don't - but. I have quoted the research from Bell Labs in my various papers and writings. My favorite reference is William B. Snow's 1953 paper that is republished in the AES Anthology of Stereophonic Techniques. In it, he defines all of the auditory perspective systems. Yes, among other things, you have a LOT of reading up to do, not the least of which is on fundamental definitions. Thanks for the tip. So let me read to you for a minute: From R. Vermeulen's paper on Stereo Reverberation (JAES, vol. 6, no. 2, pp. 124 - 130, 1958 April): NECESSITY FOR AUGMENTED REVERBERATION It is true that by suitable positioning of the microphone we can pick up reverberation sound from the hall and reproduce the plolongation of the sound. But here again, we are apt to make the same mistake in that we reproduce only one and - of course - the only measurable characteristic of the sound field, viz, the reverberation time, but neglect its spatial distribution. The loudspeakers of a stereophonic set can never reproduce the sound field in the concert hall with any accuracy in the home; how indeed could they do so with only the data from two microphones at their disposal? Neither can they deliver to the listener's ears exact copies of the instantaneous sound pressure at the place of the microphones, if only because the listeners are free to move their heads and are sitting at different places. The loudspeakers can only produce a quite different sound field, which will nevertheless give an impression that resembles the original in certain respects. But not in all rexpects, beause they are only capable of simulating sound sources in the space between them. Thus stereophony can only widen the "hole in the wall of the concert hall" to a "large window" but it cannot give the listener the impression that he is present in the auditorium. It cannot imitate the sound reflected from all sides by the ceiling and the walls. This does not matter as long as the reproduction takes place in the concert hall itself where the ceiling and the walls are present to produce reverberated sound with the desired properties. In a living room, however, the absence of enough reverberated sound or at least its different character places the listener in the positon of an outsider." He goes on to describe how to simulate the reverberant field by means of a distribution of loudspeakers. Permit me one more quote, this time from Blauert (the well-known Spatial Hearing book, p 282) in describing the two basic approaches to transmitting a spatial impression across a distance of space and time: "In principle two approaches to solving this problem are possible. One consists of generating a sound field in the playback room that corresponds largely to that in the recording room. Such an electroacoustically generated sound field is called a 'synthetic sound field.' The second approach proceeds from the assumption that an optimal acoustical reproduction is attained if the subject's ear input signals are collected, transmitted, and reproduced. Processes employing this technique are called binaural or 'head related' since a head, usually a dummy head, is used in collecting the ear input signals." His "synthetic sound field" is a large collection of microphones leading to a similar number of speakers around the subject in an anechoic environment, in an attempt to duplicate the original field as much as possible, or necessary. Surround sound in the home theater system is a simplification of this approach, which most of us realize by common sense. You might want to do some more reading on this subject, starting with those two sources. It is possible that you could use some reinforcement in acoustics and psychoacoustics. Gary Eickmeier |
#7
Posted to rec.audio.high-end
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Mind Stretchers
On 5/30/2012 2:41 AM, Gary Eickmeier wrote:
"Dick wrote in message ... large snip Thanks for the tip. So let me read to you for a minute: From R. Vermeulen's paper on Stereo Reverberation (JAES, vol. 6, no. 2, pp. 124 - 130, 1958 April): NECESSITY FOR AUGMENTED REVERBERATION It is true that by suitable positioning of the microphone we can pick up reverberation sound from the hall and reproduce the prolongation of the sound. my emphasis. Quite a relevant point that I've been endeavoring to have you understand. Thank you for pointing out the reference - there is no "spatial" information in the signal. Level and arrival time. That's it. But here again, we are apt to make the same mistake in that we reproduce only one and - of course - the only measurable characteristic of the sound field, viz, the reverberation time, Note - time...the *only* measurable characteristic. There is no other recording parameter to capture "spatial" information. Here's your answer to your "smartass" question. Rhetorical on your part evidently. but neglect its spatial distribution. The loudspeakers of a stereophonic set can never reproduce the sound field in the concert hall with any accuracy in the home; how indeed could they do so with only the data from two microphones at their disposal? Wow, this guy's good. You indeed can never reproduce the sound field in the venue when using only two microphones for the recording. Why? Simply because, as he states above, the spatial information is not encoded in the signal. Note, recordings using 3 mics, or any number of close-miked instruments panned into place will suffer the exact same effects. Wonder where I've heard that before... snip He goes on to describe how to simulate the reverberant field by means of a distribution of loudspeakers. And corresponding microphones. This in no wise supports your method of taking a signal devoid of non-temporal spatial information (i.e. no incident angle info) and by bouncing the entire - direct and reverberant - signal off the wall(s), thereby introducing an artificially delayed acoustic wave superimposed on the directly radiated signal (which also contains both the direct and reverberant data). While you may sense that as spaciousness, it is clearly less accurate. And as Mr. Pierce accurately observed, morphing the term "stereo" to incorporate any number of speakers in any configuration is, IMO, clearly a dodge. If you want to discuss surround sound - the term you clearly know is universally applied - say so. Keith |
#8
Posted to rec.audio.high-end
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Mind Stretchers
Actually I suspect that 4 mikes is enough to establish a
soundfield and am quite sure that 16 would be. That is for the soundfield impinging on one spot of course. The four mikes would be four omnis in a spaced tetrahedron, say 10 inches on a side. The sixteen would be in groups of four coincident ones at the points of the same tetrahedron. These would consist of one omni and three figure 8 ones, the three figure 8 ones being pointed up-down, east-west and north-south. Or, alternatively, four cardioids pointing out from the center of the tetrahedron. This would allow computerized localization of a single sound source generating a sine wave, or localization of the original and reflections of a point impulse source. Of course doing this for a whole orchestra would be an immense and probably somewhat impractical computer programming job. The accuracy would decrease at low frequencies of course. Doug McDonald |
#9
Posted to rec.audio.high-end
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Mind Stretchers
"Doug McDonald" wrote in message
... Actually I suspect that 4 mikes is enough to establish a soundfield and am quite sure that 16 would be. That is for the soundfield impinging on one spot of course. The four mikes would be four omnis in a spaced tetrahedron, say 10 inches on a side. The sixteen would be in groups of four coincident ones at the points of the same tetrahedron. These would consist of one omni and three figure 8 ones, the three figure 8 ones being pointed up-down, east-west and north-south. Or, alternatively, four cardioids pointing out from the center of the tetrahedron. This would allow computerized localization of a single sound source generating a sine wave, or localization of the original and reflections of a point impulse source. Of course doing this for a whole orchestra would be an immense and probably somewhat impractical computer programming job. The accuracy would decrease at low frequencies of course. OK as long as we are stretching minds here, permit me to do another thought experiment - which could easily be a real experiment if we had time etc. We will record a singer with one mike, a drum kit with another, a piano and perhaps a bass, all with their own microphones. They are playing in a good hall or studio. While recording the piano on the left side of the room we also catch the early reflected sound from front and left side wall. Similarly for all the other instruments and voice. The recording now contains information about both the direct sound of that performer and some of the reverberant from near them. We will play back each channel to a fairly omnidirectional speaker placed in a position similar to the performer it is reproducing. The singer, for example, will be a sound image that is nailed in the center of your room and pulled out from the front wall of the room. You can now walk all around and magically hear the singer where she belongs, three dimensionally singing right there in front of you. Any problems so far? We recorded her with but one mike, paid no attention whatsoever to the human hearing mechanism, HRTF, spacing of ears, dummy heads, none of it. When we listen to her on playback, we each use our own human hearing mechanism and HRTF and all that to hear her, each in our own way in our own head, so there is no question of worrying about any of that. The piano will be played from a speaker or speakers on the left side, and if it is basically omnidirectional it will cast some reflected sound toward the front and left side walls just as the live piano did, and you recorded. The spatial impression we will all get from this arrangement on playback will be the same for all of us and very similar to the live event, and again we can walk all around and the piano will remain nailed right there where it belongs. Similarly for all instruments, the whole system becoming more like a "model" of the live event than a "picture" taken from one spot in the studio with a fixed perspective. Is this getting spooky or what? Stay with me. What we have here is a field-type system, a system which was recorded and reproduced with no reference whatsoever to the human hearing mechanism or the position of a typical listener to the live event. We play it back by positioning the speakers in another acoustic space, in a certain way that models the playback situation after the original, and we have a "stereo" phonic, meaning "solid" sounding reproduction of the original. If the original was played in a more live acoustic, like a church or a cave or a good concert hall, we would have preserved most of the temporal aspect of that reverberation, and on playback it is up to us to recostruct the spatial aspect with correct radiation patterns and positioning of the speakers and enhancent from some surrond speakers, fed by either additional mikes or signal processing. If we take that approach, we get a pretty good impression of the sound of the original event, even though the temporal aspect of our playback room is superimposed on the recording a little. But wait - what if we use quite directional speakers on the same recording? Well, this would be a big mistake, because then all of the sound, the direct and the reverberation, would be forced to come from the location of that player, an unnatural sounding situation. The piano, for example, would have all of its output coming from the speaker box rather than from both the speaker and the left side wall. It would be more "accurate" if you compare the wrong aspects to each other - the electrical input signal would be JUST LIKE the acoustical output of the thing - but the resultant sound would be nothing like the original - accurate but not realistic! What a mess. This experiment is the paradigm for the field-type system that we call "stereophonic sound" in general, presented to you as a basis for understanding the simplification of it that we call - well, the same word is unfortunately used. The extremely fortunate psychoacoustic principle that permits us to simplify this more elaborate model down to fewer speakers and microphones is called summing localization. This is the idea that you can image anywhere between two coherent sources by means of intensity or time difference or a combination of the two, permitting the impression of many instruments from just two or more mikes and speakers. So the "big picture" of what we are doing with "stereo" is something like close miking the soundstage rather than each individual instrument, but the principle remains the same. We can get away with reproducing an entire symphony orchestra with just two speakers if we position them in a certain way and let them reflect a certain amount of their output from the appropriate wall of the playback room etc etc in a way that models the playback after the (typical) live event. This grand simplification can be engineered with time/intensity trading so that you can walk across the room and have the imaging remain solid and hear them from some degree of variable perspective. You can also engineer the directivity index of the speakers so that the RANGE OF RATIOS of direct to reflected sound is similar to that in the (typical) concert hall with the very much greater distance of the listener from the source. As I said, there is very much more to study about all of this, but we will get nowhere until we can understand the basic principle and how it differs from what we have been doing (or not paying any attention to) for so many years. It's a whole deal. Gary Eickmeier |
#10
Posted to rec.audio.high-end
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Mind Stretchers
On Thu, 31 May 2012 07:44:41 -0700, Doug McDonald wrote
(in article ): Actually I suspect that 4 mikes is enough to establish a soundfield and am quite sure that 16 would be. That is for the soundfield impinging on one spot of course. The four mikes would be four omnis in a spaced tetrahedron, say 10 inches on a side. I suggest that 4 omni-directional microphones, that close together. would yield mono unless some precautions were taken to isolate the microphones from each other (as in Kimber's Iso-Mike setup. http://www.isomike.com/gallery/gallery.html). |
#11
Posted to rec.audio.high-end
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Mind Stretchers
On Thu, 31 May 2012 11:05:01 -0700, Gary Eickmeier wrote
(in article ): "Doug McDonald" wrote in message ... Actually I suspect that 4 mikes is enough to establish a soundfield and am quite sure that 16 would be. That is for the soundfield impinging on one spot of course. The four mikes would be four omnis in a spaced tetrahedron, say 10 inches on a side. The sixteen would be in groups of four coincident ones at the points of the same tetrahedron. These would consist of one omni and three figure 8 ones, the three figure 8 ones being pointed up-down, east-west and north-south. Or, alternatively, four cardioids pointing out from the center of the tetrahedron. This would allow computerized localization of a single sound source generating a sine wave, or localization of the original and reflections of a point impulse source. Of course doing this for a whole orchestra would be an immense and probably somewhat impractical computer programming job. The accuracy would decrease at low frequencies of course. OK as long as we are stretching minds here, permit me to do another thought experiment - which could easily be a real experiment if we had time etc. We will record a singer with one mike, a drum kit with another, a piano and perhaps a bass, all with their own microphones. They are playing in a good hall or studio. While recording the piano on the left side of the room we also catch the early reflected sound from front and left side wall. Similarly for all the other instruments and voice. The recording now contains information about both the direct sound of that performer and some of the reverberant from near them. We will play back each channel to a fairly omnidirectional speaker placed in a position similar to the performer it is reproducing. The singer, for example, will be a sound image that is nailed in the center of your room and pulled out from the front wall of the room. You can now walk all around and magically hear the singer where she belongs, three dimensionally singing right there in front of you. Any problems so far? We recorded her with but one mike, paid no attention whatsoever to the human hearing mechanism, HRTF, spacing of ears, dummy heads, none of it. When we listen to her on playback, we each use our own human hearing mechanism and HRTF and all that to hear her, each in our own way in our own head, so there is no question of worrying about any of that. The piano will be played from a speaker or speakers on the left side, and if it is basically omnidirectional it will cast some reflected sound toward the front and left side walls just as the live piano did, and you recorded. The spatial impression we will all get from this arrangement on playback will be the same for all of us and very similar to the live event, and again we can walk all around and the piano will remain nailed right there where it belongs. Similarly for all instruments, the whole system becoming more like a "model" of the live event than a "picture" taken from one spot in the studio with a fixed perspective. Is this getting spooky or what? Stay with me. What we have here is a field-type system, a system which was recorded and reproduced with no reference whatsoever to the human hearing mechanism or the position of a typical listener to the live event. We play it back by positioning the speakers in another acoustic space, in a certain way that models the playback situation after the original, and we have a "stereo" phonic, meaning "solid" sounding reproduction of the original. If the original was played in a more live acoustic, like a church or a cave or a good concert hall, we would have preserved most of the temporal aspect of that reverberation, and on playback it is up to us to recostruct the spatial aspect with correct radiation patterns and positioning of the speakers and enhancent from some surrond speakers, fed by either additional mikes or signal processing. If we take that approach, we get a pretty good impression of the sound of the original event, even though the temporal aspect of our playback room is superimposed on the recording a little. But wait - what if we use quite directional speakers on the same recording? Well, this would be a big mistake, because then all of the sound, the direct and the reverberation, would be forced to come from the location of that player, an unnatural sounding situation. The piano, for example, would have all of its output coming from the speaker box rather than from both the speaker and the left side wall. It would be more "accurate" if you compare the wrong aspects to each other - the electrical input signal would be JUST LIKE the acoustical output of the thing - but the resultant sound would be nothing like the original - accurate but not realistic! What a mess. This experiment is the paradigm for the field-type system that we call "stereophonic sound" in general, presented to you as a basis for understanding the simplification of it that we call - well, the same word is unfortunately used. The extremely fortunate psychoacoustic principle that permits us to simplify this more elaborate model down to fewer speakers and microphones is called summing localization. This is the idea that you can image anywhere between two coherent sources by means of intensity or time difference or a combination of the two, permitting the impression of many instruments from just two or more mikes and speakers. So the "big picture" of what we are doing with "stereo" is something like close miking the soundstage rather than each individual instrument, but the principle remains the same. We can get away with reproducing an entire symphony orchestra with just two speakers if we position them in a certain way and let them reflect a certain amount of their output from the appropriate wall of the playback room etc etc in a way that models the playback after the (typical) live event. This grand simplification can be engineered with time/intensity trading so that you can walk across the room and have the imaging remain solid and hear them from some degree of variable perspective. You can also engineer the directivity index of the speakers so that the RANGE OF RATIOS of direct to reflected sound is similar to that in the (typical) concert hall with the very much greater distance of the listener from the source. As I said, there is very much more to study about all of this, but we will get nowhere until we can understand the basic principle and how it differs from what we have been doing (or not paying any attention to) for so many years. It's a whole deal. Gary Eickmeier From experience, I can tell you that this doesn't work. The direct sound from the instrument is so much louder than any hall reverb, that once you pad-down the gain on the microphone preamp/mixer so as to not overload the electronics, the reverb will be completely lost . That's one of the things that some engineers/producers like about close-up multimiking. The sound from the instrument being miked is so dominate compared the sounds of instruments around it or any hall acoustics that it is quite isolatory. I.E. essentially all you get on that track is the sound of that instrument, with other instruments around it or any hall acoustics being severely attenuated. In places where that isolation isn't enough, of course, they use sound absorbent panels called gobos. These types of recordings often rely on artificial reverb added to the mix during production. As I've said before, I find this kind of overproduction both unnecessary and extremely artificial sounding. The concert goer does not hear those instruments so close-up and they sound different in the hall than they do close-up on the stage. For instance, from the audience, a dozen violins playing together sounds like a string section, but that same dozen violins, individually close-miked and then electronically mixed together in a mixing console, sounds like 12 individual violins. It does NOT sound like a string section, This is true of other instruments as well. There is a story told about a famous 20th Century composer (I believe it was Copland, but don't quote me) who was listening to the playback of one his works recorded by Columbia in the late 1960's using multi-mike/multi-track techniques. At one point in the playback, the composer jumped up and yelled "what's that tuba doing in the sound?" A beaming producer piped up and said. "We're real proud of that. We were having a difficult time getting that on tape, so we used a contact microphone on it and now you can hear it perfectly!" "You idiot, " responded the composer, "that tuba line is there to help keep the brasses on time, It's not meant to be heard by the audience!" So much for multi-miking and multi-track technology. Only one stereo pair is needed for suburb stereo sound, if the engineer knows what he is doing. All the spatial cues are there, Width, height, and depth (also called front-to-back). In a properly made, real stereo recording, the triangle shimmers up in the air, hovering over the percussion section (just as in real life), you can hear that the brasses are behind the woodwinds and you can close your eyes and pick-out each instrument (during solos) with holographic precision. If you need reverb, that can be added with another stereo pair in the back of the hall. |
#12
Posted to rec.audio.high-end
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Mind Stretchers
On Thu, 31 May 2012 11:05:01 -0700, Gary Eickmeier wrote
OK as long as we are stretching minds here, permit me to do another thought experiment - which could easily be a real experiment if we had time etc. We will record a singer with one mike, a drum kit with another, a piano and perhaps a bass, all with their own microphones. They are playing in a good hall or studio. While recording the piano on the left side of the room we also catch the early reflected sound from front and left side wall. Similarly for all the other instruments and voice. The recording now contains information about both the direct sound of that performer and some of the reverberant from near them. First problem - every mic picks up a different view of the reflections of the room. The strongest reflections often don't come from objects near the musical instrument, because on a stage the only such thing near is the floor and the floor does not give a distinct reflection because every part of it is a different distance away from the mic and the instrument. Secondly, floors reflect sound away from the mic and the instrument because the angle of reflection is the complement of the angle of incidence. Far better - close mic the instruments, and also mic the room. We will play back each channel to a fairly omnidirectional speaker placed in a position similar to the performer it is reproducing. The singer, for example, will be a sound image that is nailed in the center of your room and pulled out from the front wall of the room. You can now walk all around and magically hear the singer where she belongs, three dimensionally singing right there in front of you. Any problems so far? The biggest problem with this is that while the listener can partially dereverberate the room, his ability to do so is limited. In many rooms the many reflections from the omni speakers give you a real mess. Been there, done that with Ohm F's. The second problem is that listeners don't want to walk around speakers as a rule. They want to sit in their favorite seat, so anything you invest or pay for that "walk around" realism is lost and not appreciated. Most speakers are used in suboptimal places in suboptimal rooms. This very much favors directional speakers. If you have a fairly dead listening room (not a bad idea), the best you can say is that omni speakers are at least not a serious problem. Speakers with controlled directivity will still sound at least as good. Again, I've heard this comparison just lately and Gary knows where. ;-) |
#13
Posted to rec.audio.high-end
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Mind Stretchers
On 5/31/2012 11:02 PM, Audio Empire wrote:
On Thu, 31 May 2012 07:44:41 -0700, Doug McDonald wrote (in ): Actually I suspect that 4 mikes is enough to establish a soundfield and am quite sure that 16 would be. That is for the soundfield impinging on one spot of course. The four mikes would be four omnis in a spaced tetrahedron, say 10 inches on a side. I suggest that 4 omni-directional microphones, that close together. would yield mono unless some precautions were taken to isolate the microphones from each other (as in Kimber's Iso-Mike setup. http://www.isomike.com/gallery/gallery.html). I'm not proposing that the 4-mike arrangement would be "playable". The 16 mike one would, of course, since it is a gross superset of both the standard coincident cardioid pair and the spaced cardioid pair. It could mimic those exactly, if the mikes were ideal examples of their nominal pattern, using linear combinations. I was in fact referring to using these for a computerized soundfield analysis. Doug McDonald |
#14
Posted to rec.audio.high-end
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Mind Stretchers
"Arny Krueger" wrote in message
... On Thu, 31 May 2012 11:05:01 -0700, Gary Eickmeier wrote The biggest problem with this is that while the listener can partially dereverberate the room, his ability to do so is limited. In many rooms the many reflections from the omni speakers give you a real mess. Been there, done that with Ohm F's. The second problem is that listeners don't want to walk around speakers as a rule. They want to sit in their favorite seat, so anything you invest or pay for that "walk around" realism is lost and not appreciated. Most speakers are used in suboptimal places in suboptimal rooms. This very much favors directional speakers. Hi Arn - No, nothing I have been trying to relate favors directional speakers. We talked about the spatial nature of speakers and rooms being audible, so that if that characteristic is very different from live it will not, cannot, sound the same. Here is another paradigm for you to digest: Think of an experimenter who wants to investigate this spatial business. He puts three omnidirectional speakers on the stage of a concert hall, runs some pink noise thru them, and records them. He gets back home and plays the recording on his "hi fi" system with its highly directional speakers. But no matter how he equalizes it, it just doesn't sound the same. Comes the dawn, he realizes the problem. His live sound had a completely different spatial pattern than his reproduction attempt at home. It couldn't sound the same! If you have a fairly dead listening room (not a bad idea), the best you can say is that omni speakers are at least not a serious problem. Speakers with controlled directivity will still sound at least as good. Again, I've heard this comparison just lately and Gary knows where. ;-) Yes, and it's no big secret - it is part of public knowledge: http://home.provide.net/~djcarlst/SLReport10.05.pdf I would also direct your attention to Siegfried Linkwitz's listening room, with its highly reflective front end. These properties were duplicated in the test room, which was good, and which reinforced what I have been saying for 30 years. The speakers were positioned as I have recommended as well. Gary Eickmeier |
#15
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Mind Stretchers
On Sat, 2 Jun 2012 09:08:53 -0700, Gary Eickmeier wrote
(in article ): "Arny Krueger" wrote in message ... On Thu, 31 May 2012 11:05:01 -0700, Gary Eickmeier wrote The biggest problem with this is that while the listener can partially dereverberate the room, his ability to do so is limited. In many rooms the many reflections from the omni speakers give you a real mess. Been there, done that with Ohm F's. The second problem is that listeners don't want to walk around speakers as a rule. They want to sit in their favorite seat, so anything you invest or pay for that "walk around" realism is lost and not appreciated. Most speakers are used in suboptimal places in suboptimal rooms. This very much favors directional speakers. Hi Arn - No, nothing I have been trying to relate favors directional speakers. We talked about the spatial nature of speakers and rooms being audible, so that if that characteristic is very different from live it will not, cannot, sound the same. Here is another paradigm for you to digest: Think of an experimenter who wants to investigate this spatial business. He puts three omnidirectional speakers on the stage of a concert hall, runs some pink noise thru them, and records them. He gets back home and plays the recording on his "hi fi" system with its highly directional speakers. But no matter how he equalizes it, it just doesn't sound the same. Comes the dawn, he realizes the problem. His live sound had a completely different spatial pattern than his reproduction attempt at home. It couldn't sound the same! No, it couldn't sound the same, and not necessarily for the reasons you give. First of all, unless the pink noise (defined as 1/f or, noise with equal power density over the entire spectrum) is close-miked, the recording venue will alter the spectrum. Secondly, and most importantly, microphones are not flat in frequency response, so therefore when recorded, the microphones will change the character of the noise so that it is no longer "pink". |
#16
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Mind Stretchers
"ScottW" wrote in message
... I find the arguments posed lend themselves greatly to favoring directional speakers. If the spatial nature of the original venue is captured in the recording and one wishes to create the illusion of the original venue in the playback room, limiting the interaction of the original recording with the playback room enhances the illusion. And how exactly does that work? Does the sound from each speaker enter the appropriate ear and fool you into hearing "into" the recorded acoustic space? Tell me just what you think is happening with stereo. Omnidirectional speakers at home isn't going to fix that. He's got a better chance at coming close through a near field setup with directional speakers than omnis in a new room creating a unique to that room spatial pattern. Maybe if you put the speakers almost on top of your ears, that would be the best stereo of all. No, nobody is confusing stereo with binaural. How could I even think it. http://home.provide.net/~djcarlst/SLReport10.05.pdf I don't understand how this subjective assessment of "auditory scene" has any relevance to accurate recreation of a sound field. You're kidding, right? I'm fairly confident the Orions dynamic capability (ability to create the illusion of the raw power of an orchestra) is well beyond anything a box with RS in wall speakers can create yet that didn't seem to be a factor in your assessment. I wonder why? Why do you say that? Where did you get that? Scottie, you're a great man - I read your stuff in the Recording magazine - but like most others you have not thought all that much about stereo theory beyond "two ears, two speakers." But it just does not work that way. Everyone here is just spouting back to me what he already believed before, and not trying to see what I am saying. I don't know how I can "unhook" you guys from your preconceptions. If someone could just give me a nod, an inkling, some interest or partial agreement, maybe you see my point about the spatial nature of the original vs the reproduction, anything but all this "I didn't believe that before so it can't be true" crap. Just give me something. I can't see where I have left out anything of the explanation. Just start your next post with "Gary, that is an interesting point about the________________________ Gary Eickmeier |
#17
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Mind Stretchers
"Gary Eickmeier" wrote in message
... "Arny Krueger" wrote in message ... The biggest problem with this is that while the listener can partially dereverberate the room, his ability to do so is limited. In many rooms the many reflections from the omni speakers give you a real mess. Been there, done that with Ohm F's. The second problem is that listeners don't want to walk around speakers as a rule. They want to sit in their favorite seat, so anything you invest or pay for that "walk around" realism is lost and not appreciated. Most speakers are used in suboptimal places in suboptimal rooms. This very much favors directional speakers. Hi Arn - No, nothing I have been trying to relate favors directional speakers. We talked about the spatial nature of speakers and rooms being audible, so that if that characteristic is very different from live it will not, cannot, sound the same. It can't sound the same no matter what, at least at the current state of technology. Here is another paradigm for you to digest: Think of an experimenter who wants to investigate this spatial business. He puts three omnidirectional speakers on the stage of a concert hall, runs some pink noise thru them, and records them. He gets back home and plays the recording on his "hi fi" system with its highly directional speakers. But no matter how he equalizes it, it just doesn't sound the same. Comes the dawn, he realizes the problem. His live sound had a completely different spatial pattern than his reproduction attempt at home. It couldn't sound the same! Excluded middle argument. If you have a fairly dead listening room (not a bad idea), the best you can say is that omni speakers are at least not a serious problem. Speakers with controlled directivity will still sound at least as good. Again, I've heard this comparison just lately and Gary knows where. ;-) Yes, and it's no big secret - it is part of public knowledge: http://home.provide.net/~djcarlst/SLReport10.05.pdf I would also direct your attention to Siegfried Linkwitz's listening room, with its highly reflective front end. These properties were duplicated in the test room, which was good, and which reinforced what I have been saying for 30 years. The speakers were positioned as I have recommended as well. So Gary are you pulling an AL Gore on us and claiming to have invented LEDE? ;-) |
#18
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Mind Stretchers
"Arny Krueger" wrote in message
... "Gary Eickmeier" wrote in message ... I would also direct your attention to Siegfried Linkwitz's listening room, with its highly reflective front end. These properties were duplicated in the test room, which was good, and which reinforced what I have been saying for 30 years. The speakers were positioned as I have recommended as well. So Gary are you pulling an AL Gore on us and claiming to have invented LEDE? ;-) No, LEDE is just the opposite of what should be done. If you can't see that, then I have failed to communicate. There ARE a lot of researchers and writers, however, who have gone before me and said very similar things to what I am advocating, so I am not a screwball advocating some iconoclast nonsense. Just trying to synthesize everything that is known and a few details that I have discovered about it. This whole discussion is interesting to me because - well, primarily because I am trying to tell fellow lovers of good sound what causes some of the audible effects and problems that have consequences on system setup and can improve their sound, and also partly because it shows how stead and unmovable the audio industry is. It is more like "camps" of warring factions rather than truly interested enthusiasts. You have encountered this EXACT phenomenon with high end audiophile resistance to double blind testing and especially the ABX approach and all that it taught you. So how does it feel to be scorned and laughed at by certain camps? You can write your ass off and it will not penetrate. I have great respect for most of the respondents in this group, including you, so I was hoping to get at least some agreement on some areas or inroads, but it's more like trying to convince a Chevy man to get a Ford. I just hope upon hope that some of the correspondents are not right, that it is just a matter of taste and I am tilting at windmills. There HAS to be something more scientific about it than that. Gary Eickmeier |
#19
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Mind Stretchers
On 6/6/2012 5:55 PM, Gary Eickmeier wrote:
"Arny wrote in message ... "Gary wrote in message ... big snip I just hope upon hope that some of the correspondents are not right, that it is just a matter of taste and I am tilting at windmills. I haven't seen any correspondents saying that it is *just* a matter of taste. Quite the opposite. Everyone has acknowledged that there are many areas, especially in the recording process, where clearly things can improve. What is clear, however, is that you consistently refuse to acknowledge that preference plays a major role, and thus there simply cannot be any universally acknowledged *best*, or most realistic presentation. There HAS to be something more scientific about it than that. There is nothing remotely unscientific about evaluating and understanding listener preferences, and recognizing how such preferences impact the universality or efficacy of any particular engineering solution. As long as you continue to think there is *a* single correct way to create realism, you will be tilting at windmills. Keith |
#20
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Mind Stretchers
"KH" wrote in message
... On 6/6/2012 5:55 PM, Gary Eickmeier wrote: big snip I just hope upon hope that some of the correspondents are not right, that it is just a matter of taste and I am tilting at windmills. I haven't seen any correspondents saying that it is *just* a matter of taste. Quite the opposite. Everyone has acknowledged that there are many areas, especially in the recording process, where clearly things can improve. What is clear, however, is that you consistently refuse to acknowledge that preference plays a major role, and thus there simply cannot be any universally acknowledged *best*, or most realistic presentation. I haven't talked all that much about preference, that is not the point of the thread. I couldn't have refused to acknowledge preference's role in audio. There HAS to be something more scientific about it than that. There is nothing remotely unscientific about evaluating and understanding listener preferences, and recognizing how such preferences impact the universality or efficacy of any particular engineering solution. As long as you continue to think there is *a* single correct way to create realism, you will be tilting at windmills. Didn't talk about a single best way, acknowledged many times that there are many ways to make a recording, for example, such as Blumlein, spaced omni, ORT-F, etc. Just talking about what is audible about speakers and rooms, and attempting to offer a new way to look at the big picture of sound in rooms and compare that to the live situation. I offered in the What Can We Hear thread that the spatial nature of sound was the main stumbling block, or difference, between live and reproduced. I said that we can hear speaker positioning and different radiation patterns and offered some reasons for certain positioning and the result of mis-positioning them. If a hole in the middle effect is a matter of preference, then more power to you. If a boxy sound in speakers is a preference, then hey. For me, it really helps in my recording efforts to be able to "see" sound patterns or the probable implications of microphone positioning or technique w respect to the final result, because often I cannot hear that final result until I get home and produce the recording and play it on my big system. On the recording site, all I have is a headphone to make sure the channels are all working and I am getting some good strong signal. I place the mikes more visually than anything else, because there is no monitoring setup isolated from the performers. In setting up a home audio system, I appreciate a more visual understanding of sound as a basis for room treatment, speaker selection, and positioning. Within all of those ranges, there are a lot of possible preferences, but that was not what I was hoping to talk about, and you are right, that would be pointless. If ANYBODY got ANYTHING out of this thread, please tell me. Gary Eickmeier |
#21
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Mind Stretchers
On 6/7/2012 6:34 PM, Gary Eickmeier wrote:
wrote in message ... On 6/6/2012 5:55 PM, Gary Eickmeier wrote: big snip I just hope upon hope that some of the correspondents are not right, that it is just a matter of taste and I am tilting at windmills. I haven't seen any correspondents saying that it is *just* a matter of taste. Quite the opposite. Everyone has acknowledged that there are many areas, especially in the recording process, where clearly things can improve. What is clear, however, is that you consistently refuse to acknowledge that preference plays a major role, and thus there simply cannot be any universally acknowledged *best*, or most realistic presentation. I haven't talked all that much about preference, Well, yes. Quite. That's the point I was making; you want to divorce preference from "realism" in reproduction, and that is a basic error IMO. that is not the point of the thread. And that is, again IMO, your basic misunderstanding of the goal of reproduction in the home. Given that such reproduction must try to create an illusion of the recorded event, in very large part it is a matter of preference, and trying to examine the problem without acknowledging that such a constraint exists is perfectly reasonable; for your personal satisfaction. If you want to extrapolate your 'theory' to a broader audience, you are doomed to failure if you ignore that basic precept. I couldn't have refused to acknowledge preference's role in audio. Actually, you've done so repeatedly. Explicitly by your continual insistence that box speakers are "wrong*, direct sound is *wrong*, that in essence, anything you don't like, or that doesn't represent *your* internal reference for realism is *wrong*. You do so implicitly by choosing to ignore any references to preference that others bring up. This thread being the exception. There HAS to be something more scientific about it than that. There is nothing remotely unscientific about evaluating and understanding listener preferences, and recognizing how such preferences impact the universality or efficacy of any particular engineering solution. As long as you continue to think there is *a* single correct way to create realism, you will be tilting at windmills. Didn't talk about a single best way, acknowledged many times that there are many ways to make a recording, for example, such as Blumlein, spaced omni, ORT-F, etc. That's a dodge Gary. You have acknowledged that recordings can improve, but have repeatedly insisted that your reflected sound method is the only approach to realism in reproduction. That is a simple fact. Just talking about what is audible about speakers and rooms, and attempting to offer a new way to look at the big picture of sound in rooms and compare that to the live situation. I offered in the What Can We Hear thread that the spatial nature of sound was the main stumbling block, or difference, between live and reproduced. And no one has argued that point, with the stipulation that capturing that nature in the recording does not happen today. I said that we can hear speaker positioning and different radiation patterns and offered some reasons for certain positioning and the result of mis-positioning them. If a hole in the middle effect is a matter of preference, then more power to you. If a boxy sound in speakers is a preference, then hey. And these statements clearly demonstrate that you are not getting my point. You appear unable to accept that others may simply not *hear* it your way. Neither of these descriptions, "a hole in the middle" or "boxy sound" is of any interest to any of us here (to my knowledge). But all of your writing leads me to conclude that if a particular implementation sounds a particular way to *you*, then that is the only way it could be interpreted (or interpreted correctly). Thus anyone who prefers such an implementation must, perforce, like the sound as *you* perceive it to be, i.e. conforming to your own internal definitions. If my system sounds real to me, and you hear it and state, as fact, "it sounds like a hole in the middle", you are simply being *wrong* about *my* perception of it. When I hear most dipoles, and certainly 901's (unless augmented with significant additional directly radiated sound - like the L-100's I mentioned previously), I hear an artificially large, diffuse soundstage, with directional clues that seem totally wrong. My perception is not open to your agreement or disagreement. You really need to understand that point. snip In setting up a home audio system, I appreciate a more visual understanding of sound as a basis for room treatment, speaker selection, and positioning A point without controversy. Within all of those ranges, there are a lot of possible preferences, but that was not what I was hoping to talk about, I know. And the only cogent reasons I can see to ignore preferences in such a discussion would be if you deny, or are unaware of their effects, or you believe yours preferences to be correct, and others must be brought to "see the light". and you are right, that would be pointless. Again, your interpretation of what I wrote is 180° off the mark. I said ignoring preference in the discussion renders the discussion moot. It is pointless to discuss your preferences in the context of right and wrong. It certainly is appropriate to discuss your preferences, why you hold them relative to certain implementations, what cues or facets of reproduction trigger your perception of realism, how you can record to preserve those clues, and how you arrive at a setup that optimally reproduces those perceptual clues. However, stating that listening to direct radiating speakers is "wrong" because they don't fit your visual model is a value judgment you simply do not get to make for the world at large. If ANYBODY got ANYTHING out of this thread, please tell me. Well, I don't know. Answer the question you ignored before, and I'll tell you if there was anything to be learned, IMO: If you and I completely disagree about whether a specific stereo implementation (yours, mine, AE's, etc.) is realistic or not, is one of us wrong? Yes or no? Irrespective of that question, however, I can say that if you really believe what you stated previously, namely; "Yes... well... as I agreed earlier, the recording is a **new work of art**, using the original as a stepping off point..."emphasis mine and: "...an audio reproduction event is also a NEW event, a new work of art if you will, and not JUST a replica of the live event. I have made a few recordings now that I enjoy more than the live event I was recording!" then one thing I have gotten is that there's virtually no overlap between your goals, and mine (or most anyone else's here unless I miss my guess). Mine is reproduction, yours appears to be creation of some new "performance" event. The two are not congruent; your creation-of-event vision being the very antithesis of "hi fidelity". Keith |
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