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Post by ROWUK on Aug 18, 2019 4:26:55 GMT 10
I am not sure that most audibility thresholds are a major "problem" in music playback. Even at live concerts, we have noise, reflections from the side walls and ceiling, balance issues based on proximity to the stage. In row 15 we hardly have response above 12KHz - and no one is bothered.
I believe that we can learn to deal with many things. I am also sure that through experience we can either blend out issues or get posessed by them - it is purely an emotional issue, not a technical one. So are the audibility thresholds for those that cannot blend out issues - or is there a threshold that would be a common denominator or starting point for something called "realistic playback"? Do we need psychological manipulation to appreciate recorded music?
When considering playback geometry, perhaps the goal is not "reproduction", rather a creation of a plausible space - a new, exclusive audio event. This is certainly possible with 2 speakers and acoustic relevant recordings. For studio pop recordings, I often think about why "pinpoint" localization is desirable. It NEVER happens live. Even when I sit in a club and play small group jazz, the other performers on stage with me are not pinpoint localizable. If we think about "live" bass - how often do we even get close at home? The softness and size regardless of venue is something that hardly I have ever experienced in audio. It is a distortion of perspective - is it measurable? Do we need experience in live venues to have an audibility threshold?
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Post by Audiophile Neuroscience on Aug 18, 2019 13:03:43 GMT 10
So the concept of "accuracy" is a very seductive term until we understand the provisos that go along with it - "accuracy" is defined relative to audibility - measurements which are considered below auditory thresholds are considered inaudible & therefore differences in measurements at this low level are not considered of audible importance. So "accuracy" should really be termed "below audible threshold" but, AFAIK, these thresholds were established using mono signals with simple tones, not binaural signals with complex dynamic signals (such as music) In a broader sense accuracy means how strongly the measure represents the true value of what is being measured. An accurate test tells you no more or less than the true value of what the tool measures. The question then is what do you make of that measure and in particular the concept of validity. Validity takes on different meanings depending on context, a valid argument may be logical flow from premises, whereas in testing procedures it generally means how strongly (accurately) you are measuring what you think you are measuring. This often means a need for concurrent validity i.e comparison to a gold standard to verify the original test is doing its job and that involves knowing sensitivity and specificity measures. Once establishing all of the above then comes external validity which means can you generalize the results outside the one test situation and internal validity, the extent (strength) that there is only one explanation for the relationships between variables. that may seem like a lot of statistical mumbo jumbo but it just means that a measurement is meaningless and useless unless it satisfies certain parameters.An amplifier measured as bigger will obviously not necessarily sound better although a correlation may exist. The flawed logic is easy to spot. I'm not sure I understand fully about measurements below audibility. I would think the same tenets hold true in that I would ask is it a valid measure. It may be incredibly precise but have little to do with audility. Isn't that what THD of x.000000234 means? A precisely meaningless measurement. So my humble question remains what are these things that are being measured below audibility and do they matter in the first place? IF (a big if) you assume they are a valid measure of audibility I have no problem then that they are more sensitive in detecting their target than the human ear. It would mean they are measuring below audibility, defining the threshold of audibility as well as subsequent JND (just noticeable difference). I think, as you say, there is no such beast for the perception of complex musical experiences. This brings us to another related term that is often used "transparency" & it is argued that it is a binary choice, there are no degrees of "transparency" - an audio device, it is argued, is either transparent or it's not. Again this is related to auditory perception - can we tell the difference between two audio devices? if we can't then it is considered "transparent" if its measurements are considered to identify an "accurate" device. I have always thought of transparency as shades of I'm not dismissing measurements, in fact I'm hoping that new measurements, new ways of measuring or new ways of analysing measurements, can bridge the divide between measurements & auditory perception. In fact I'm always interested in new devices +1 My criteria for what/where is auditory truth is tied up in music reproduction that makes the most believable illusion & engages my interest the most. When I find that I'm not engaged with music that I know well, it's usually the fault of the reproduction system. One thing I find is that there's no "ultimate truth" (or at least I haven't experienced it yet) - that we often believe the sound can't get any better & then we hear something which is better, more realistic, more engaging. +1 I find it difficult to put one's finger on exactly what is different in the reproduced soundfield which makes for a more realistic, more believable illusion. My premise is that once the individual sounds are more realistic, the whole presentation becomes more interesting & engages attention. To paraphrase Barry Diament, for me it is when you get a sense of the gear getting out of the way of the music. It leaves no signature, no stamp, it disappears. Just like live acoustic sound it is immediately compelling and mesmerizing I recently purchased a DAC which measures pretty exemplary according to all the standard measurements to see what/where the latest DAC chips are at, sonically. So the sound is pretty much what you get from all DACs that are designed for best measurements - nothing obviously wrong with the sound but it's not engaging - it reproduces all the notes in the right place but something is missing that engages the auditory sense & lessens the desire to listen to more music. When compared to a DAC that does present a higher level of realism I find it misses some stability or purity to the sound - for instance the subtle amplitude modulation in a singer's voice who is holding a note just isn't presented realistically - it seems curtailed - doesn't fade to silence in the way we experience in the real world. It might seem like a trivial thing when trying to itemise it to a specific in this way but when this occurs with all the reproduced sounds, it effects the whole presentation in a fundamental way This is what/where I find a move towards more "truth" in audio - the truth being "realism" +1
Cheers David
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Post by Deleted on Aug 18, 2019 16:31:14 GMT 10
Interestingly i had always assumed that the majority of audio objectivists would have leaned towards a materialistic world view i.e all things must be proven. Which seems at odds with an idiological stance that is comfortable with things not necessarily being readily explicable.
Mark
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Post by Deleted on Aug 18, 2019 16:43:48 GMT 10
Nelson Pass has some jems of wisdom sprinkled into his talks, papers and interviews. Being a physicist he does regard theory and measurements as important. His stance is that if you find a preference in listeners to different topologies or circuit tuning then you need to find out why and he has done some interesting experiments into this. For example he has discovered that listeners prefer distortion to be out is phase to the signal as this gives a feeling of depth and energy. For him, measurements serve the music but he's always pushing to understand what to measure next. www.passlabs.com/press/audio-distortion-and-feedback
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sandyk (RIP Alex, 1939 - 2021)
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About Me: Retired ex Principal Telecommunications Technical Officer with 43 years at Telstra (Australia)
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Electronics hobbyist for >65 years with DIY projects including Loudspeakers, Stereo FM tuner, S/W Regen Receiver, Superhet AM ,
Synchrodyne PLL AM tuner (Phase Lock Loop),Stereo Tape Deck, Amplifiers including I.C. types, Class A, Class AB 100W/Ch. (ETI5000) 240W/Ch. Mosfet (AEM6000) ,several DACs , numerous PSUs including VERY low noise (<4uV) types etc.for myself and friends
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Post by sandyk (RIP Alex, 1939 - 2021) on Aug 18, 2019 17:09:13 GMT 10
Nelson Pass has some jems of wisdom sprinkled into his talks, papers and interviews. Being a physicist he does regard theory and measurements as important. His stance is that if you find a preference in listeners to different topologies or circuit tuning then you need to find out why and he has done some interesting experiments into this. For example he has discovered that listeners prefer distortion to be out is phase to the signal as this gives a feeling of depth and energy. For him, measurements serve the music but he's always pushing to understand what to measure next. www.passlabs.com/press/audio-distortion-and-feedback
It's a shame that Douglas Self is so anti subjective
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sandyk (RIP Alex, 1939 - 2021)
Global Moderator
Posts: 226
About Me: Retired ex Principal Telecommunications Technical Officer with 43 years at Telstra (Australia)
I am also a Moderator in Hi Fi Critic Forum
Electronics hobbyist for >65 years with DIY projects including Loudspeakers, Stereo FM tuner, S/W Regen Receiver, Superhet AM ,
Synchrodyne PLL AM tuner (Phase Lock Loop),Stereo Tape Deck, Amplifiers including I.C. types, Class A, Class AB 100W/Ch. (ETI5000) 240W/Ch. Mosfet (AEM6000) ,several DACs , numerous PSUs including VERY low noise (<4uV) types etc.for myself and friends
Audio Industry Affiliation: NIL
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Post by sandyk (RIP Alex, 1939 - 2021) on Aug 18, 2019 17:53:37 GMT 10
Interestingly i had always assumed that the majority of audio objectivists would have leaned towards a materialistic world view i.e all things must be proven. Which seems at odds with an idiological stance that is comfortable with things not necessarily being readily explicable. Mark Mark
Most E.E.s for example, do fall into that category, with many even refusing to accept the results of their so called " Gold Standard" DBTs, even if correctly implemented , when the results don't go the way that they expected.
Alex
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Post by Audiophile Neuroscience on Aug 18, 2019 18:38:58 GMT 10
Interestingly i had always assumed that the majority of audio objectivists would have leaned towards a materialistic world view i.e all things must be proven. Which seems at odds with an idiological stance that is comfortable with things not necessarily being readily explicable. about an hour ago scumbag said: Nelson Pass has some jems of wisdom sprinkled into his talks, papers and interviews. Being a physicist he does regard theory and measurements as important. His stance is that if you find a preference in listeners to different topologies or circuit tuning then you need to find out why and he has done some interesting experiments into this. For example he has discovered that listeners prefer distortion to be out is phase to the signal as this gives a feeling of depth and energy. For him, measurements serve the music but he's always pushing to understand what to measure next. www.passlabs.com/press/audio-distortion-and-feedbackCombining your posts I would comment that some subscribe to reductionist physicalism as a form of bottom up processing and Nelson Pass possibly more a top down processing guy. Do you measure what you hear or do you hear what you measure?
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Post by ROWUK on Aug 20, 2019 5:47:44 GMT 10
I am not so sure what Mr. Pass is really "listening to". I see practical circuits, but not really Sound centered. Except for his B1 preamp, nothing has tickled my fancy - AmpCampAmp or First Watt products. My reference has been with high efficiency speakers. Maybe his stuff helps lower efficiency more?
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sandyk (RIP Alex, 1939 - 2021)
Global Moderator
Posts: 226
About Me: Retired ex Principal Telecommunications Technical Officer with 43 years at Telstra (Australia)
I am also a Moderator in Hi Fi Critic Forum
Electronics hobbyist for >65 years with DIY projects including Loudspeakers, Stereo FM tuner, S/W Regen Receiver, Superhet AM ,
Synchrodyne PLL AM tuner (Phase Lock Loop),Stereo Tape Deck, Amplifiers including I.C. types, Class A, Class AB 100W/Ch. (ETI5000) 240W/Ch. Mosfet (AEM6000) ,several DACs , numerous PSUs including VERY low noise (<4uV) types etc.for myself and friends
Audio Industry Affiliation: NIL
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Post by sandyk (RIP Alex, 1939 - 2021) on Aug 20, 2019 11:43:51 GMT 10
I am not so sure what Mr. Pass is really "listening to". I see practical circuits, but not really Sound centered. Except for his B1 preamp, nothing has tickled my fancy - AmpCampAmp or First Watt products. My reference has been with high efficiency speakers. Maybe his stuff helps lower efficiency more? Robin It's a shame that you have never heard Nelson Pass's big Class A (100W?) monoblocks in a very expensive and revealing system as both David and myself were able to. Their presentation of " The Storm" even though down converted to Stereo made me involuntarily jump a little, just like a real nearby lightning strike. Regards Alex
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Post by Deleted on Aug 22, 2019 8:39:09 GMT 10
I am not so sure what Mr. Pass is really "listening to". I see practical circuits, but not really Sound centered. Except for his B1 preamp, nothing has tickled my fancy - AmpCampAmp or First Watt products. My reference has been with high efficiency speakers. Maybe his stuff helps lower efficiency more? I admit that I am a NP fanboy. I have read just about everything he's published, interviews he conducted and listened to a lot of his presentations at the Burning Amp Festival. He does a lot of listening and he gets a lot of people to listen to his gear when he is designing it. Some of his First Watt circuits are, from a purely engineering point of view, highly unpractical but they are intended to represent a train of thought on a particular topology. Here is a bit of an insight into the man:https://parttimeaudiophile.com/2018/02/21/an-interview-with-hifi-legend-nelson-pass/ " JS:You are famous for continuing to experiment, especially with your side brand, First Watt. How much better-sounding do you think amplifiers can get? Do you think there are still some major advances waiting to be discovered? NP: I don’t know how much better. I assume there are advances, but I think they will have more to do with progress in cognitive perception than in electronic parts and topology. I intend to keep plugging away, mostly because I still find it interesting and fun. " " NP: I like measurements, and I use them all the time, but they don’t get the last word. Generally, there isn’t much conflict between what we measure and what we like to hear. I’ve spent decades working to correlate good sound with measurements, and we have a reasonable picture of what works, and you see that in our products. These represent our own listening tastes, and appeal to a large enough portion of customers to keep us in business. With low-order harmonics, there is agreement that low-order distortion is much less offensive than high-order harmonics and IM (Inter modulated) sidebands, and this drove the development of the Threshold 800A back in 1975, where the nature of the distortion was considered as important as the size of the “single number.” By 1991 when I started Pass Labs, I began to focus more on the specific character of second and third harmonics, and slowly settled into a character where negative-phase second harmonic dominates at low levels, segueing into symmetric third harmonic at higher power. The second fosters an illusion of expanded space and localization, and the third seems to improve dynamics. The distortion of these amplifiers is still quite low, but they are not sterile.
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Post by Deleted on Aug 22, 2019 8:45:01 GMT 10
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Post by Deleted on Aug 22, 2019 8:52:18 GMT 10
Interestingly i had always assumed that the majority of audio objectivists would have leaned towards a materialistic world view i.e all things must be proven. Which seems at odds with an idiological stance that is comfortable with things not necessarily being readily explicable. about an hour ago scumbag said: Nelson Pass has some jems of wisdom sprinkled into his talks, papers and interviews. Being a physicist he does regard theory and measurements as important. His stance is that if you find a preference in listeners to different topologies or circuit tuning then you need to find out why and he has done some interesting experiments into this. For example he has discovered that listeners prefer distortion to be out is phase to the signal as this gives a feeling of depth and energy. For him, measurements serve the music but he's always pushing to understand what to measure next. www.passlabs.com/press/audio-distortion-and-feedbackCombining your posts I would comment that some subscribe to reductionist physicalism as a form of bottom up processing and Nelson Pass possibly more a top down processing guy. Do you measure what you hear or do you hear what you measure? Yes, I laboured through a thread on (I think) DIYaudio a few weeks ago about a guy who took great lengths to do a double blind test on 10 samples of music. Some were played directly from a hard drive and others were bit perfect ones that were being streamed. They measured both to make sure they were "bit perfect". The subject of the test got 9 out of 10 right. Cue endless debate and obfuscation.
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sandyk (RIP Alex, 1939 - 2021)
Global Moderator
Posts: 226
About Me: Retired ex Principal Telecommunications Technical Officer with 43 years at Telstra (Australia)
I am also a Moderator in Hi Fi Critic Forum
Electronics hobbyist for >65 years with DIY projects including Loudspeakers, Stereo FM tuner, S/W Regen Receiver, Superhet AM ,
Synchrodyne PLL AM tuner (Phase Lock Loop),Stereo Tape Deck, Amplifiers including I.C. types, Class A, Class AB 100W/Ch. (ETI5000) 240W/Ch. Mosfet (AEM6000) ,several DACs , numerous PSUs including VERY low noise (<4uV) types etc.for myself and friends
Audio Industry Affiliation: NIL
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Post by sandyk (RIP Alex, 1939 - 2021) on Aug 22, 2019 9:40:07 GMT 10
Combining your posts I would comment that some subscribe to reductionist physicalism as a form of bottom up processing and Nelson Pass possibly more a top down processing guy. Do you measure what you hear or do you hear what you measure? Yes, I laboured through a thread on (I think) DIYaudio a few weeks ago about a guy who took great lengths to do a double blind test on 10 samples of music. Some were played directly from a hard drive and others were bit perfect ones that were being streamed. They measured both to make sure they were "bit perfect". The subject of the test got 9 out of 10 right. Cue endless debate and obfuscation. Several years ago I sent well respected E.E. and Magazine editor Martin Colloms copies of "Dire Straits -Private Investigations" tracks via the Internet which sounded different due to PSU changes etc. with one version, yet still had identical .md5 checksums. Martin and an assistant performed a series of 6 separate DBT sessions over a period of several months, with 8 repeats in each session. Martin did however have a decided advantage, as he had previously heard a Master copy of this particular track, and knew it well. They obtained 48 out of 48 positive results. The results were published in Hi Fi Critic magazine Vol.6 No.1, but detailed much more in several Hi Fi Critic forum threads. However, most E.E's in various forums still refuse to accept the results, despite the DBT sessions being correctly implemented. Are you able to provide a link to this DIY Audio thread ? I am a DIY Audio member also, and went through the same type of exercise in DIY Audio more than 10 years ago, even sending a comparison CD to moderator Netlist (Hugo) Hugo did a hatchet job on both myself and Electronics Tech Erin from Melbourne who had also confirmed my results. This reminds me that I should contact Erin and let him know about this new forum.
Alex
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Post by Audiophile Neuroscience on Aug 22, 2019 9:47:17 GMT 10
I admit that I am a NP fanboy. I have read just about everything he's published, interviews he conducted and listened to a lot of his presentations at the Burning Amp Festival. He does a lot of listening and he gets a lot of people to listen to his gear when he is designing it. Some of his First Watt circuits are, from a purely engineering point of view, highly unpractical but they are intended to represent a train of thought on a particular topology. Here is a bit of an insight into the man:https://parttimeaudiophile.com/2018/02/21/an-interview-with-hifi-legend-nelson-pass/ " JS:You are famous for continuing to experiment, especially with your side brand, First Watt. How much better-sounding do you think amplifiers can get? Do you think there are still some major advances waiting to be discovered? NP: I don’t know how much better. I assume there are advances, but I think they will have more to do with progress in cognitive perception than in electronic parts and topology. I intend to keep plugging away, mostly because I still find it interesting and fun. " " NP: I like measurements, and I use them all the time, but they don’t get the last word. Generally, there isn’t much conflict between what we measure and what we like to hear. I’ve spent decades working to correlate good sound with measurements, and we have a reasonable picture of what works, and you see that in our products. These represent our own listening tastes, and appeal to a large enough portion of customers to keep us in business. With low-order harmonics, there is agreement that low-order distortion is much less offensive than high-order harmonics and IM (Inter modulated) sidebands, and this drove the development of the Threshold 800A back in 1975, where the nature of the distortion was considered as important as the size of the “single number.” By 1991 when I started Pass Labs, I began to focus more on the specific character of second and third harmonics, and slowly settled into a character where negative-phase second harmonic dominates at low levels, segueing into symmetric third harmonic at higher power. The second fosters an illusion of expanded space and localization, and the third seems to improve dynamics. The distortion of these amplifiers is still quite low, but they are not sterile. Hi Mark. I applaud NP for listening and trying to correlate measurements with, and be concordant with subjective listening experiences. For me, listening is the end game, its the part that pleases me. NP ( as far as I understand) states that he produces designs with certain sonic characteristics,like his children, and probably this is where I struggle. I don't mean from an engineering POV that there may be designs better suited for difficult speakers etc but from a sonic POV, having different sonic characters. Personally I go for neutrality and transparency to the extent that quality can be guessed. I have heard oodles of NP amps and owned one. They all to my ear sounded lovely and "warm". I don't want gear with a noticeable sonic signature that draws attention to itself. Combining your posts I would comment that some subscribe to reductionist physicalism as a form of bottom up processing and Nelson Pass possibly more a top down processing guy. Do you measure what you hear or do you hear what you measure? Yes, I laboured through a thread on (I think) DIYaudio a few weeks ago about a guy who took great lengths to do a double blind test on 10 samples of music. Some were played directly from a hard drive and others were bit perfect ones that were being streamed. They measured both to make sure they were "bit perfect". The subject of the test got 9 out of 10 right. Cue endless debate and obfuscation. I participated in that thread and think it produced some very interesting outcomes beyond the p=0.01 = 1 in 100 chance of guessing.
Mani (the subject) is a physicist by background and once the test protocol was altered he was able to hone in on the differences. Like many others I see blind audio testing in audio fora a scientifically flawed methodology but blinding to eliminate bias an absolutely necessary part of any test methodology. IOW it is difficult, if not impossible as attested to by the red pill/blue pill thread, to set up a proper blind test. Secondly, eliminating one bias does not make the whole methodolgy valid especially if by doing so it introduces other biases and inter-dependent variables.
Thats just my perspective as a (medical) scientist and I know other scientists who will say, well its better than nothing so lets run with it. The only audio truth here, I believe, is we just don't know. I believe some (most ?) will wanna believe what they wanna believe no matter how much evidence you throw at them. We find what we (think) we know and see what we look for.
Cheers
David
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Post by Deleted on Aug 22, 2019 10:58:01 GMT 10
I have heard oodles of NP amps and owned one. They all to my ear sounded lovely and "warm". I don't want gear with a noticeable sonic signature that draws attention to itself. If you're ever up in Brisbane, I would invite you to have a listen to my Pass Labs XA25. This is a very low distortion, zero feedback, Class A design which might provide a revelation as far as the sonic signature of PL amps I am running it with a PS Audio BHK preamp which is a decidedly low distortion / colouration take on tubes (it's a hybrid Mosfet/ double triode design). Mark
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