plissken Posted July 8, 2017 Share Posted July 8, 2017 2 minutes ago, christopher3393 said: ...another small step toward normalizing contempt? If given a choice between normalizing contempt and self delusion. I mean if I had to make a sighted choice. Link to comment
plissken Posted July 8, 2017 Share Posted July 8, 2017 1 hour ago, 4est said: What do you mean by this in context? I meant in the context that has been openly talked about: Q: What equipment constitutes 'transparent' playback A: A lot of mastering grade equipment Response: Well if it's good enough and isn't missing any information. That's why you need a subjective high end audiophile to provide that. You CAN NOT add information once it is lost in the production process. We have sound REPRODUCTION equipment. What ever it is given is what it has. No matter DSP, Upsampling, EQ, cables, lifters, Hookum sticks. You can only have a reproduction chain that does the least amount of damage to the source as it makes it way through our systems. That's why I'm a shortest path first. pkane2001 1 Link to comment
AJ Soundfield Posted July 8, 2017 Share Posted July 8, 2017 11 minutes ago, christopher3393 said: ...another small step toward normalizing contempt? No, utter contempt of logic, reason, scientific method, intellectual honesty, ridicule of measuring "measureists" , etc, etc. all considered quite normal. No steps. Link to comment
Popular Post Jud Posted July 8, 2017 Author Popular Post Share Posted July 8, 2017 Been too busy to do much posting the past week or so. Looking in, I see a lot of pretty uninformative sniping back and forth, and a choice posed between contempt and self-delusion. I’ll take neither, thanks very much, and opt for good conversation with friends instead, during which I may learn a thing or two. Speaking of which, @semente, we were having such a conversation a few days ago when I had to leave off. Later today or tomorrow I’ll try to get back to that. Right now, more work to do. daverich4, MikeyFresh, mourip and 2 others 5 One never knows, do one? - Fats Waller The fairest thing we can experience is the mysterious. It is the fundamental emotion which stands at the cradle of true art and true science. - Einstein Computer, Audirvana -> optical Ethernet to Fitlet3 -> Fibbr Alpha Optical USB -> iFi NEO iDSD DAC -> Apollon Audio 1ET400A Mini (Purifi based) -> Vandersteen 3A Signature. Link to comment
AJ Soundfield Posted July 8, 2017 Share Posted July 8, 2017 11 minutes ago, Jud said: Right now, more work to do. No matter what the case involves, I'll be your expert witness. I've trained myself and passed all my own tests A+ I can hear stuff others can't. I know more about audio than...the scientists know, believe me. Link to comment
jabbr Posted July 8, 2017 Share Posted July 8, 2017 12 hours ago, plissken said: You can apply any post processing you want. You not add lost fidelity. Regardless if the loss is in choice of mastering equipment or the choices of the mastering or mixing engineer. This is stemming from someone asking what hardware was 'transparent'. I answered that question. 11 hours ago, jabbr said: That depends entirely on what you mean by "lost fidelity" exactly. In many cases a deconvolution does exactly that, restores fidelity. If by "lost fidelity" you mean "lost information" then no, but that's an important reason to "oversample" which allows introduction of error at a level less than the LSB. 1 hour ago, plissken said: Oversample a 192kbps mp3 all you like. MP3 lossy compression is obviously lossy. We aren't presumably dealing with MP3 in the context of this forum although the principles are important for audio in general. Using a real (for us) situation like CD Redbook, 16/44.1 if the mastering engineer applies an equalization profile its possible it could run into the headroom available in 16 bits, and information might be lost. Instead if the file is supplied as 24 bits there might be enough headroom that the equalization is reversible by applying an "invert" equalization (just the opposite of the original eq) and then no information will be lost. This would be termed a "reversible" operation. If the mastering equalization is a very simple convolution, the reverse equalization would be a very simple deconvolution, and in this case reversible. So back to my original question: do you consider "loss of fidelity" only irreversible convolutions or do you consider reversible convolutions (where the deconvolution restores full fidelity)? The functional analysis convolution-deconvolution had been developed precisely to "restore" signals that have been modified. Teresa 1 Custom room treatments for headphone users. Link to comment
plissken Posted July 8, 2017 Share Posted July 8, 2017 4 minutes ago, jabbr said: MP3 lossy compression is obviously lossy. We aren't presumably dealing with MP3 in the context of this forum although the principles are important for audio in general. Using a real (for us) situation like CD Redbook, 16/44.1 if the mastering engineer applies an equalization profile its possible it could run into the headroom available in 16 bits, and information might be lost. Instead if the file is supplied as 24 bits there might be enough headroom that the equalization is reversible by applying an "invert" equalization (just the opposite of the original eq) and then no information will be lost. This would be termed a "reversible" operation. If the mastering equalization is a very simple convolution, the reverse equalization would be a very simple deconvolution, and in this case reversible. So back to my original question: do you consider "loss of fidelity" only irreversible convolutions or do you consider reversible convolutions (where the deconvolution restores full fidelity)? The functional analysis convolution-deconvolution had been developed precisely to "restore" signals that have been modified. I understand inverse filters. It's still not restoring information that isn't there. Again: Someone asked what equipment tends to be transparent. The answer I provided was a lot of mastering grade equipment. The retort is that it could err on capturing information. Ok. So what then? Nothing you can do about that regardless of ANY and ALL processing you do. I don't care if it's biquad filtering. Linkwitz Transform, convolution-deconvolution, up sampling, transcoding, etc... Link to comment
jabbr Posted July 8, 2017 Share Posted July 8, 2017 6 minutes ago, plissken said: I understand inverse filters. It's still not restoring information that isn't there. Deconvolution is a generalization of "inverse filter" and in the same way that a bandwidth limited analog signal can be entirely represented in 16/44.1 and then reconstructed, a deconvolution can restore a signal that has been altered. Back to the question: do you know the information isn't there? That is the crux of the question. If you are sure the information isn't there then it can't be re-created. Like refocussing an image to remove "blur" seemingly lost information can be restored. It really depends. OK you added that clarification -- yes "mastering grade" equipment would tend to be transparent, and I assume works at high bitrate, depth for the reasons I've outlined. Custom room treatments for headphone users. Link to comment
plissken Posted July 8, 2017 Share Posted July 8, 2017 5 minutes ago, jabbr said: do you know the information isn't there? That is the crux of the question. If you are sure the information isn't there then it can't be re-created. Like refocussing an image to remove "blur" seemingly lost information can be restored. It really depends. Don't get off on tangent that I didn't bring into the conversation. AGAIN: Question by other: What equipment constitutes transparent playback Answer by me: Probably most mastering grade audio equipment Retort by other: It may not capture everything and that's why we need subjective audiophile approached systems. You are barking up the wrong tree. Systems can apply dither and other methods to effect mathematically approximation but it still is not a true reconstruction in the XOR sense. Look, I totally get what you are saying and these systems can be really good, but they aren't mathematically perfect. Link to comment
pkane2001 Posted July 8, 2017 Share Posted July 8, 2017 21 minutes ago, jabbr said: The functional analysis convolution-deconvolution had been developed precisely to "restore" signals that have been modified. It's not so simple in the real world. EQ-convolved signal is further corrupted by noise and other signals (e.g., leakage currents, jitter, EMI, feedback loops, etc.) For deconvolution to recover the 'original' signal, you need a very precise model of the corrupting signal. In most real-world cases, this is very hard to derive. Because of this, an estimate is commonly used as the deconvolution kernel. An estimate may help with signal recovery in some cases, but it can also destroy or corrupt signal in others. There are other complexities related to deconvolution, for example that the process is iterative and has to be applied over many small increments. The number of iterations is itself a variable, and has to be estimated based on some other measure which is often not known precisely. -Paul DeltaWave, DISTORT, Earful, PKHarmonic, new: Multitone Analyzer Link to comment
jabbr Posted July 8, 2017 Share Posted July 8, 2017 4 minutes ago, plissken said: Don't get off on tangent that I didn't bring into the conversation. AGAIN: Question by other: What equipment constitutes transparent playback Answer by me: Probably most mastering grade audio equipment Agreed ... I think we all are guilty of responding to short quips out of context, as well as writing that is too brief to convey the context or intent... Custom room treatments for headphone users. Link to comment
AJ Soundfield Posted July 8, 2017 Share Posted July 8, 2017 15 minutes ago, jabbr said: yes "mastering grade" equipment would tend to be transparent I wonder how many audiophiles would prefer a TASCAM over a piece of $50k audiophile bling, in a sighted evaluation, 2 months or not? Hmmm Link to comment
pkane2001 Posted July 8, 2017 Share Posted July 8, 2017 1 hour ago, plissken said: You can only have a reproduction chain that does the least amount of damage to the source as it makes it way through our systems. That's why I'm a shortest path first. That's been my approach, as well: shorten and simplify. This often has helped drive the choice of components for my systems. I guess some might call it a bias -Paul DeltaWave, DISTORT, Earful, PKHarmonic, new: Multitone Analyzer Link to comment
Jud Posted July 8, 2017 Author Share Posted July 8, 2017 14 minutes ago, pkane2001 said: That's been my approach, as well: shorten and simplify. This often has helped drive the choice of components for my systems. I guess some might call it a bias Though of course all such approaches have their advantages and disadvantages once one gets down to specifics. Many folks like to include the extra step of DSP for room equalization, for example. One never knows, do one? - Fats Waller The fairest thing we can experience is the mysterious. It is the fundamental emotion which stands at the cradle of true art and true science. - Einstein Computer, Audirvana -> optical Ethernet to Fitlet3 -> Fibbr Alpha Optical USB -> iFi NEO iDSD DAC -> Apollon Audio 1ET400A Mini (Purifi based) -> Vandersteen 3A Signature. Link to comment
mansr Posted July 8, 2017 Share Posted July 8, 2017 51 minutes ago, AJ Soundfield said: I wonder how many audiophiles would prefer a TASCAM over a piece of $50k audiophile bling, in a sighted evaluation, 2 months or not? Hmmm My Tascam is great. Guess I'm not a real audiophile. Link to comment
jabbr Posted July 8, 2017 Share Posted July 8, 2017 59 minutes ago, pkane2001 said: For deconvolution to recover the 'original' signal, you need a very precise model of the corrupting signal. In most real-world cases, this is very hard to derive. The room correction that @Jud just mentioned is an example of a deconvolution that is measured rather than estimated. Custom room treatments for headphone users. Link to comment
AJ Soundfield Posted July 8, 2017 Share Posted July 8, 2017 1 minute ago, mansr said: My Tascam is great. Guess I'm not a real audiophile. Just another poor deaf Mid-Fi measureist who begrudges those who can afford to hear better. Wait, did I just sound contemptuous??? Nah.... Link to comment
pkane2001 Posted July 8, 2017 Share Posted July 8, 2017 Just now, jabbr said: The room correction that @Jud just mentioned is an example of a deconvolution that is measured rather than estimated. I'm not aware of any DSP that uses deconvolution to apply EQ. Convolution -- yes. Deconvolution is a complex mathematical process that doesn't have a simple solution. Convolution is much, much easier in comparison. -Paul DeltaWave, DISTORT, Earful, PKHarmonic, new: Multitone Analyzer Link to comment
AJ Soundfield Posted July 8, 2017 Share Posted July 8, 2017 4 minutes ago, pkane2001 said: I'm not aware of any DSP that uses deconvolution to apply EQ. DSP "room correction" also has nothing to do with the original signal(s). It is based purely on one transduction of it. Link to comment
plissken Posted July 8, 2017 Share Posted July 8, 2017 14 minutes ago, jabbr said: The room correction that @Jud just mentioned is an example of a deconvolution that is measured rather than estimated. 2+X=4. No information is missing. It simply hasn't been calculated yet. When we end up with 2 as the answer we know what the original hard value was. 2+X+X=4 can be computed, the answers are literally infinite and we may, or more likely, may not be able to reconstitute the original missing values. But do we care if the end goal is an answer of 4 if nothing else is negatively impacted? Link to comment
jabbr Posted July 8, 2017 Share Posted July 8, 2017 18 minutes ago, pkane2001 said: I'm not aware of any DSP that uses deconvolution to apply EQ. Convolution -- yes. Deconvolution is a complex mathematical process that doesn't have a simple solution. Convolution is much, much easier in comparison. Convolution and deconvolution are a pair and map to division in the Fourier domain. Consider the system as the convolution and the deconvolution is a Fourier domain divisor that results in 1. In room correction, the deconvolution is simply 1/impulse response. It is really as simple as dividing the Fourier domain signal by the measured impulse response. To clarify deconvolution is simply 1/convolution in the Fourier domain. By measuring an impulse response, the deconvolution is thus measured. Of course software like HQPlayer applies this transform in the time domain in realtime in SDM so @Miska could provide the math Custom room treatments for headphone users. Link to comment
pkane2001 Posted July 8, 2017 Share Posted July 8, 2017 2 minutes ago, jabbr said: Convolution and deconvolution are a pair and map to division in the Fourier domain. Consider the system as the convolution and the deconvolution is a Fourier domain divisor that results in 1. In room correction, the deconvolution is simply 1/impulse response. It is really as simple as dividing the Fourier domain signal by the measured impulse response. To clarify deconvolution is simply 1/convolution in the Fourier domain. By measuring an impulse response, the deconvolution is thus measured. Of course software like HQPlayer applies this transform in the time domain in realtime in SDM so @Miska could provide the math As I said, not so simple in the real world, in the presence of noise and other distortions that are also convolved with the signal. plissken 1 -Paul DeltaWave, DISTORT, Earful, PKHarmonic, new: Multitone Analyzer Link to comment
Popular Post christopher3393 Posted July 8, 2017 Popular Post Share Posted July 8, 2017 Back to the original question, if you don't mind. In his big book (Sound Reproduction, p.345) Floyd Toole mentions that disputes btw subjectivists and objectivists are not new, then includes the following quote from a '60s article on the origin of psychoacoustics: Quote In 1852, as Helmholz began his research, the sciences and the arts were at loggerheads. The cold rationalism seemingly preached by Darwin’s biology, Faraday’s new atomic chemistry, and Gustav Magnus’ physics were being strenuously opposed by a hostile school of arch-Romanticists, who believed that exposure of the roots of art as mere extensions of matter and energy meant the complete destruction of all beauty. So maybe this is all a bit bigger than we tend to recognize...Maybe. Here's a little presentation (more like a tease) that places the notion of objectivity in a larger context than usual for this forum. Hope you find it interesting: https://prezi.com/j1s4xv9nis5l/historicizing-objectivity/ semente and Superdad 2 Link to comment
semente Posted July 8, 2017 Share Posted July 8, 2017 1 hour ago, christopher3393 said: Back to the original question, if you don't mind. In his big book (Sound Reproduction, p.345) Floyd Toole mentions that disputes btw subjectivists and objectivists are not new, then includes the following quote from a '60s article on the origin of psychoacoustics: So maybe this is all a bit bigger than we tend to recognize...Maybe. Here's a little presentation (more like a tease) that places the notion of objectivity in a larger context than usual for this forum. Hope you find it interesting: https://prezi.com/j1s4xv9nis5l/historicizing-objectivity/ Thanks, that's a nice summary. But I wonder why Dürer was stated as an example, since he never got to see the Pope's Rhinocerus... "Science draws the wave, poetry fills it with water" Teixeira de Pascoaes HQPlayer Desktop / Mac mini → Intona 7054 → RME ADI-2 DAC FS (DSD256) Link to comment
jabbr Posted July 8, 2017 Share Posted July 8, 2017 2 hours ago, pkane2001 said: As I said, not so simple in the real world, in the presence of noise and other distortions that are also convolved with the signal. Life is implementation dependent Custom room treatments for headphone users. Link to comment
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