sandyk Posted June 6, 2019 Share Posted June 6, 2019 Incidentally, FWIW,not so long back Teresa couldn't stand RBCD, as something about it irritated her, but high res versions didn't . Teresa and Ishmael Slapowitz 1 1 How a Digital Audio file sounds, or a Digital Video file looks, is governed to a large extent by the Power Supply area. All that Identical Checksums gives is the possibility of REGENERATING the file to close to that of the original file. PROFILE UPDATED 13-11-2020 Link to comment
Popular Post Kal Rubinson Posted June 6, 2019 Popular Post Share Posted June 6, 2019 6 hours ago, lucretius said: So the question is: How can this benefit be achieved if some part of the audio playback chain (including speakers) does not reproduce the ultrasonic frequencies? Because the interaction that results in changes in the audible range has already occurred in the performance and can be captured without ultrasonic frequency response in the reproduction chain. Hugo9000, Ralf11, sandyk and 4 others 6 1 Kal Rubinson Senior Contributing Editor, Stereophile Link to comment
Popular Post lucretius Posted June 6, 2019 Popular Post Share Posted June 6, 2019 9 minutes ago, Kal Rubinson said: Because the interaction that results in changes in the audible range has already occurred in the performance and can be captured without ultrasonic frequency response in the reproduction chain. Overtones are overtones. If you cut the ultrasonic overtones out, they cannot affect the audible range. Teresa and Shadders 1 1 mQa is dead! Link to comment
Kal Rubinson Posted June 6, 2019 Share Posted June 6, 2019 15 minutes ago, lucretius said: Overtones are overtones. If you cut the ultrasonic overtones out, they cannot affect the audible range. Why do you think that a microphone cannot transduce intermodulations? crenca 1 Kal Rubinson Senior Contributing Editor, Stereophile Link to comment
Popular Post tmtomh Posted June 6, 2019 Popular Post Share Posted June 6, 2019 7 hours ago, lucretius said: This is from @Teresa and appears to be the main argument for hi-res: "No one (to my knowledge) has ever said we can hear ultrasonic frequencies. The reason to reproduce them is because musical instruments have overtones as high as 102.4 KHz." " … audio energy exists as upper overtones of musical instruments and has an effect on the lower frequencies which we do hear directly. When listening to music we hear the fundamental note and its overtones shape the timbre, this is why an oboe and a clarinet sound different when playing the same note as their overtone series is different. The more overtones available to shape the timbre of the fundamental tone the more accurate the timbre is IMHO." *********************** So the question is: How can this benefit be achieved if some part of the audio playback chain (including speakers) does not reproduce the ultrasonic frequencies? I would respectfully point out a logical gap in this argument for high-res. An oboe and a clarinet do indeed sound different when playing the same note, and their overtone series are indeed different. But they sound different because the overtones in the audible range are different. This is not evidence of the influence of ultrasonic frequencies on the frequencies we hear in the audible range. Now that said, I will freely admit that I don't have the detailed expertise to know whether or not the presence of ultrasonic sound waves in a listening room will change a person's auditory experience versus the same musical data with the ultrasonics filtered out. But let's assume for the moment that the presence of ultrasonics does somehow change the dispersion characteristics in the listening space of sound waves that are in the audible range. Even if that's true, my problem with this argument for high-res is, why is it always assumed that these ultrasonic effects on the audible soundwaves are positive, beneficial effects? After all, we listen to music with extra frequency information in it all the time: it's called intermodulation distortion and harmonic distortion, and generally it's considered desirable to minimize that. So if a recording has ultrasonic frequencies in it - even ones generated by the original instruments - then wouldn't those frequencies increase the likelihood of intermodulation distortion in the audible range? Granted, if every instrument is perfectly in tune, the intermod distortion will mimic harmonic distortion because it will all be octave integer distortion - but added harmonic distortion still is not what we're wanting, is it? Finally, in many (most?) situations, the ultrasonic info in a recording is not just perfect octave overtones of musical instruments - it includes potentially all manner of junk produced by microphones, recording and production equipment, and/or electronic instruments. And those ultrasonics definitely will produce increased, non-harmonic intermodulation distortion when they interact with the audible frequencies. So as with so many things in audiophilia - vinyl production and playback, tubes, filterless DACs, R2R DACs, zero-feedback amp designs - the claim being made here ultimately is that a signal with more distortion is higher fidelity, because of the distortion. I am willing to go so far as to consider that a higher-distortion signal might in some circumstances sound perceptually preferable to some people as a euphonic effect. But I cannot agree with any argument that posits euphonic distortion as a consistent, reliable, or objective cause of better sound. lucretius and Confused 1 1 Link to comment
lucretius Posted June 6, 2019 Share Posted June 6, 2019 56 minutes ago, Kal Rubinson said: Why do you think that a microphone cannot transduce intermodulations? I suspect the answer involves the difference between radio frequencies and sound frequencies. However, I'll let the technical folk answer this one. In any case, it sounds like you are suggesting that ultrasonic sound is distortion. mQa is dead! Link to comment
Shadders Posted June 6, 2019 Share Posted June 6, 2019 32 minutes ago, tmtomh said: So if a recording has ultrasonic frequencies in it - even ones generated by the original instruments - then wouldn't those frequencies increase the likelihood of intermodulation distortion in the audible range? Hi, This would not occur. If you examine an intermodulation test, then the two frequencies, assumed to be 18kHz and 19kHz are at power levels such that the power amplifier setting is 1watts, 10watts, or 100watts. A reasonable amplifier will have intermodulation at approximately -70dB for 100watts in 8ohms, and much lower for the lower powers. The ultrasonic energy in recordings is at -40dB for 10kHz and above, reducing to -60dB for 20kHz. This means the power in the 10kHz to 20kHz range will not produce intermodulation that is measurable. See the following : https://www.stereophile.com/content/benchmark-media-systems-ahb2-power-amplifier-measurements For 50watts into 8ohms, the 1kHz intermodulation product is at -76dB. If the power in the 10kHz to 20kHz is at most -40dB, then this translates to 5mW power at 10kHz, and 50uW at 20kHz. In the ultrasonics it is even lower. Even if we assume it is -76dB intermods for such low powers, this then translates to -99dBW, which is 125pico-watts of intermodulation power. Again, it will be even lower for ultrasonics - the lower power generates even lower intermodulation products, such that they cannot be measured. Of course, this assume a class A/B amplifier....... class D has its own issues. So, we do not need high resolution, and certainly do not need MQA to provide a lossy, aliasing sound, for which we can't hear the ultrasonics. Regards, Shadders. tmtomh 1 Link to comment
firedog Posted June 6, 2019 Share Posted June 6, 2019 1 hour ago, Kal Rubinson said: Because the interaction that results in changes in the audible range has already occurred in the performance and can be captured without ultrasonic frequency response in the reproduction chain 1 hour ago, lucretius said: Overtones are overtones. If you cut the ultrasonic overtones out, they cannot affect the audible range. Kal is correct. The overtones don't exist by themselves in a vacuum. BTW, are you aware that many microphones - especially many of the most well regarded vintage ones - can't capture ultrasonics, or even anything approaching 20khz? Or that tape machines in studios were often purposely setup not to be able to record anything over 15khz or so? Yet many who listen to 96k or192k digital transcriptions of these tapes would make the same claim as you - that its the (non-existant) ultrasonics in their hi-res files that is responsible for their good sound. crenca 1 Main listening (small home office): Main setup: Surge protector +>Isol-8 Mini sub Axis Power Strip/Isolation>QuietPC Low Noise Server>Roon (Audiolense DRC)>Stack Audio Link II>Kii Control>Kii Three (on their own electric circuit) >GIK Room Treatments. Secondary Path: Server with Audiolense RC>RPi4 or analog>Cayin iDAC6 MKII (tube mode) (XLR)>Kii Three . Bedroom: SBTouch to Cambridge Soundworks Desktop Setup. Living Room/Kitchen: Ropieee (RPi3b+ with touchscreen) + Schiit Modi3E to a pair of Morel Hogtalare. All absolute statements about audio are false Link to comment
Popular Post Paul R Posted June 6, 2019 Popular Post Share Posted June 6, 2019 So guys - you can argue this back and forth until the cows come home. Logic should be: 1. Do hi-res recordings sound different? No. ->. Stop 2. (Yes) Do they sound different because they are different masters? Yes -> choose the one you like best. Stop. 3. (No) Does the high res recording sound better? No -> Stop 4. (Yes) Why does the high res recording sound different and better? Go for it with the 14 mainstream theories of why, or invent your own. Personally, I usually think that 24/96 or above sounds a bit better than red book. The why I usually wind up at is the filters make a difference. I do not care what the filters are particularly, I just want the sound that pleases me the most. After all, I am the one listening to it. Shadders, lucretius, Hugo9000 and 2 others 5 Anyone who considers protocol unimportant has never dealt with a cat DAC. Robert A. Heinlein Link to comment
Archimago Posted June 6, 2019 Share Posted June 6, 2019 20 minutes ago, firedog said: Kal is correct. The overtones don't exist by themselves in a vacuum. BTW, are you aware that many microphones - especially many of the most well regarded vintage ones - can't capture ultrasonics, or even anything approaching 20khz? Or that tape machines in studios were often purposely setup not to be able to record anything over 15khz or so? Yet many who listen to 96k or192k digital transcriptions of these tapes would make the same claim as you - that its the (non-existant) ultrasonics in their hi-res files that is responsible for their good sound. Yup. Speaking of vintage recordings from old tape machines... Here's HDTrack's Kind of Blue, "So What" (1959), in 24/96, FFT averaged over about a minute of audio to clarify the sonic content: Notice it's essentially -95dBFS and lower noise from 21kHz onward. I see that HDTracks offers the 192kHz version as well. For $5.00 more of course... Not exactly good value IMO. crenca 1 Archimago's Musings: A "more objective" take for the Rational Audiophile. Beyond mere fidelity, into immersion and realism. R.I.P. MQA 2014-2023: Hyped product thanks to uneducated, uncritical advocates & captured press. Link to comment
Shadders Posted June 6, 2019 Share Posted June 6, 2019 5 minutes ago, Archimago said: Notice it's essentially -95dBFS and lower noise from 21kHz onward. I see that HDTracks offers the 192kHz version as well. For $5.00 more of course... Not exactly good value IMO. Hi, Yes - but the main content from 100Hz is at -35dB, so this is a difference of 60dB, as per the many download recordings analysed by Hifi News. Maybe they have not used all the bits - 8bits at the top going spare ? Regards, Shadders. Link to comment
Archimago Posted June 6, 2019 Share Posted June 6, 2019 14 minutes ago, Shadders said: Hi, Yes - but the main content from 100Hz is at -35dB, so this is a difference of 60dB, as per the many download recordings analysed by Hifi News. Maybe they have not used all the bits - 8bits at the top going spare ? Regards, Shadders. Indeed. I'm certainly not going to argue that KoB "needs" more than 16-bits either! Shadders 1 Archimago's Musings: A "more objective" take for the Rational Audiophile. Beyond mere fidelity, into immersion and realism. R.I.P. MQA 2014-2023: Hyped product thanks to uneducated, uncritical advocates & captured press. Link to comment
lucretius Posted June 6, 2019 Share Posted June 6, 2019 1 hour ago, firedog said: BTW, are you aware that many microphones - especially many of the most well regarded vintage ones - can't capture ultrasonics, or even anything approaching 20khz? Or that tape machines in studios were often purposely setup not to be able to record anything over 15khz or so? Yet many who listen to 96k or192k digital transcriptions of these tapes would make the same claim as you - that its the (non-existant) ultrasonics in their hi-res files that is responsible for their good sound. Huh? I am making the claim that the sample rates larger than 48kHz are unneeded (doesn't improve the audible range -- and especially when there are no or limited ultrasonic sounds in the higher frequencies) and many cases, unwanted (there exists ultrasonic sound in the higher frequencies but it is nothing but a source of distortion). mQa is dead! Link to comment
Popular Post Kal Rubinson Posted June 6, 2019 Popular Post Share Posted June 6, 2019 2 hours ago, lucretius said: I suspect the answer involves the difference between radio frequencies and sound frequencies. However, I'll let the technical folk answer this one. In any case, it sounds like you are suggesting that ultrasonic sound is distortion. Nope. I intentionally did not use that word. Intermodulation is the result of interaction of two signals. If the interaction is inherent, useful or appreciated, as in the case of interaction between the ultrasonic and in-band output from a musical instrument, it is not distortion. OTOH, if it is introduced by an external device and represents something that was not present in the original performance, the same phenomenon would be described as intermodulation distortion. It's like the home definition of a weed. If you need/want/like it, it's just a plant. crenca, Teresa, oPossum and 2 others 5 Kal Rubinson Senior Contributing Editor, Stereophile Link to comment
Popular Post John Dyson Posted June 6, 2019 Popular Post Share Posted June 6, 2019 15 hours ago, sandyk said: Hi John I wouldn't exactly call the rise in distortion from around 5kHz with the LME49720 (formely LM4562) a problem. (still well under .0001%) Incidentally, Mark ,who was on the original design team reported that the HA version (metal can) sounded better that the DIP version despite measuring the same with their Audio Precision gear. I found the same too. (Perhaps improved heat dissipation was the reason?) Kind Regards Alex LME49720.pdf 1.04 MB · 2 downloads You are pointing to a manufacturer's spec sheet. They always always give ideal distortion characteristics. What was the source/load impedance while measuring the distortion? If they specify the soruce/load impedances, they are usually not in the more challenging ranges. Here is a very illuminating document about the actual performance of op-amps... You might REALLY be disappointed... This kind of information (and experience) that distinguishes the experienced analog engineer vs. someone who dabbles. (It is okay to be a dabbler, it is just that data-sheets are not the be-all/end-all...) Datasheets are 'good', but are usually not 'enough' to do a competent design (either experience, or knowledge of underlying device physics/behavior like with BJTs can really be important.) Application notes won't solve all design problems beyond a data-sheet either :-). (BTW -- I have a wonderful location that has many of the old National/RCA/Signetics/NEC/etc *complete* databooks online -- *legally*). Opamp measurements: https://www.dropbox.com/s/avnprbaoxw1ng8m/opamp_distortion.pdf?dl=0 Databooks/etc: http://bitsavers.informatik.uni-stuttgart.de/components/ rando, Arpiben, Shadders and 1 other 3 1 Link to comment
John Dyson Posted June 6, 2019 Share Posted June 6, 2019 2 hours ago, Paul R said: So guys - you can argue this back and forth until the cows come home. Logic should be: 1. Do hi-res recordings sound different? No. ->. Stop 2. (Yes) Do they sound different because they are different masters? Yes -> choose the one you like best. Stop. 3. (No) Does the high res recording sound better? No -> Stop 4. (Yes) Why does the high res recording sound different and better? Go for it with the 14 mainstream theories of why, or invent your own. Personally, I usually think that 24/96 or above sounds a bit better than red book. The why I usually wind up at is the filters make a difference. I do not care what the filters are particularly, I just want the sound that pleases me the most. After all, I am the one listening to it. What 'sounds' better can be very different from something that IS objectively better. Simply because frequencies above about 20kHz cannot be heard directly doesn't mean that the IMD or other effects along with circuitry/software don't make a difference. Sometimes, there is the subjective sense that 96k/24 sounds better than 48k/24, and I cannot (will not) argue either way about that. John Link to comment
Paul R Posted June 6, 2019 Share Posted June 6, 2019 Well, does it really matter? Resource limitations have essentially become non-issues. Go with the higher sample rate to be on the safe side. 😎 Anyone who considers protocol unimportant has never dealt with a cat DAC. Robert A. Heinlein Link to comment
John Dyson Posted June 6, 2019 Share Posted June 6, 2019 26 minutes ago, Paul R said: Well, does it really matter? Resource limitations have essentially become non-issues. Go with the higher sample rate to be on the safe side. 😎 I agree that it is okay to use higher sample rates, but wider bandwidth and higher sample rates aren't needed or actually beneficial for listening (linear applications.) Also, higher bandwidth than needed/usable is a burden, not an asset. (What I mean by 'burden' is that a lot of electronics, and even some software, can create more artifacts when presented with unneeded signal.) It is my suspicion (and opinion of others) that the 'difference' often claimed for wider bandwidth source material is actually additional or change in distortion more than anything else. On the other hand, if I have to up/down convert over and over again -- I'd' rather keep the higher rate. That doesn't mean that a nice rolloff well above the audible range is a bad thing (e.g. starting at a dB or so at 25kHz.) When I rolloff for audible band, my stuff is essentially 0dB at 20kHz and a few dB at 21.5kHz. It is nailed entirely at 23.5kHz. When needing to support wide bandwidth (to make places like HDtracks happy -- they like to see lots of noise above 25kHz), my software doesn't always keep the audio and above-audio bands together, but separates them for processing -- it mitigates IMD to do the split before processing, then recombine. (In fact, doing the split in the audible bands is also helpful.) Link to comment
Ralf11 Posted June 6, 2019 Share Posted June 6, 2019 if I had to bet, I'd bet on filter slopes then there is the possibility that ultrasound can affect perception in the hearing range Teresa 1 Link to comment
lucretius Posted June 6, 2019 Share Posted June 6, 2019 2 hours ago, Kal Rubinson said: Nope. I intentionally did not use that word. Intermodulation is the result of interaction of two signals. If the interaction is inherent, useful or appreciated, as in the case of interaction between the ultrasonic and in-band output from a musical instrument, it is not distortion. OTOH, if it is introduced by an external device and represents something that was not present in the original performance, the same phenomenon would be described as intermodulation distortion. It's like the home definition of a weed. If you need/want/like it, it's just a plant. Isn't what you described as intermodulation also called intermodulation distortion (IMD)? See https://en.wikipedia.org/wiki/Intermodulation. In which case, it is distortion -- whether you prefer it or not is up to you. mQa is dead! Link to comment
Popular Post Kal Rubinson Posted June 6, 2019 Popular Post Share Posted June 6, 2019 1 hour ago, lucretius said: Isn't what you described as intermodulation also called intermodulation distortion (IMD)? See https://en.wikipedia.org/wiki/Intermodulation. In which case, it is distortion -- whether you prefer it or not is up to you. The wording of that article is unfortunately narrow because such interaction between signals occurs in the natural world. Here is another look at intermodulation which is closer to what we are dealing with here. It is also from wikipedia: https://en.wikipedia.org/wiki/Beat_(acoustics) lucretius, Confused, Hugo9000 and 1 other 3 1 Kal Rubinson Senior Contributing Editor, Stereophile Link to comment
Jud Posted June 6, 2019 Share Posted June 6, 2019 5 hours ago, lucretius said: Huh? I am making the claim that the sample rates larger than 48kHz are unneeded (doesn't improve the audible range -- and especially when there are no or limited ultrasonic sounds in the higher frequencies) and many cases, unwanted (there exists ultrasonic sound in the higher frequencies but it is nothing but a source of distortion). Hmm, the old familiar discussion again. Let's leave ultrasonics out of it - maybe there's some argument involving natural overtones, but all the discussion from Kal, firedog, you, and others is mostly correct on that score. You'd need mics that record well into the ultrasonic (which do exist), speakers with useful response that high (I think there were some Sonys with diamond tweeters; not sure what else would qualify), and still it would be arguable whether just reproducing the audible result rather than re-creating the intermodulation from overtones at home would be as good or perhaps even better. Nope, it seems to me the primary argument for hi res (if indeed it's better for otherwise equivalent masterings, another whole kettle of fish) is that you don't have to go through as much or as severe decimation filtering at the ADC end. 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
sandyk Posted June 6, 2019 Share Posted June 6, 2019 3 hours ago, John Dyson said: You are pointing to a manufacturer's spec sheet. They always always give ideal distortion characteristics. What was the source/load impedance while measuring the distortion? If they specify the soruce/load impedances, they are usually not in the more challenging ranges. John The 33 page Data sheet that I attached is possibly the most detailed opamp data sheet that I have seen. It does show numerous graphs of distortion into various loads etc., but you are correct in that it doesn't show the input resistance value used. However, in practise they are prone to instability/oscillation problems when directly driving cable loads of 100pF or more without a series output resistor. Years ago, I also had several of the National Data books that you referred to, but they are obsolete now due to much newer devices. Regards Alex LME49720.pdf Ishmael Slapowitz 1 How a Digital Audio file sounds, or a Digital Video file looks, is governed to a large extent by the Power Supply area. All that Identical Checksums gives is the possibility of REGENERATING the file to close to that of the original file. PROFILE UPDATED 13-11-2020 Link to comment
sandyk Posted June 6, 2019 Share Posted June 6, 2019 7 hours ago, Shadders said: So, we do not need high resolution, and certainly do not need MQA to provide a lossy, aliasing sound, for which we can't hear the ultrasonics. Richard Try telling that to highly respected Recording Engineers such as Barry Diament and Cookie Marenco , or the large percentage of A.S. members, especially Miska, who love their High Res and especially DSD. IIRC, one of Miska's favourite amplifiers had a 1MHZ bandwidth too. Many of Barry's recordings contain genuine musical content to past 55kHZ. If you are unable to hear the differences via a competent system between the RBCD version and the 24/96 or 24/192 version, or the same with high quality DSD recordings I feel sorry for you, as your hearing capabilities must be even worse that this 80 year old's hearing. Having said that, there is something about the SACD HF noise residuals that annoys me a little. Alex How a Digital Audio file sounds, or a Digital Video file looks, is governed to a large extent by the Power Supply area. All that Identical Checksums gives is the possibility of REGENERATING the file to close to that of the original file. PROFILE UPDATED 13-11-2020 Link to comment
Shadders Posted June 6, 2019 Share Posted June 6, 2019 2 minutes ago, sandyk said: Richard Try telling that to highly respected Recording Engineers such as Barry Diament and Cookie Marenco , or the large percentage of A.S. members, especially Miska, who love their High Res and especially DSD. IIRC, one of Miska's favourite amplifiers had a 1MHZ bandwidth too. Many of Barry's recordings contain genuine musical content to past 55kHZ. If you are unable to hear the differences via a competent system between the RBCD version and the 24/96 or 24/192 version, or the same with high quality DSD recordings I feel sorry for you, as your hearing capabilities must be even worse that this 80 year old's hearing. Having said that, there is something about the SACD HF noise residuals that annoys me a little. Alex Hi Alex, I was intending this response to illustrate that the power levels at 20kHz+ is so low, that intermodulation products are therefore extremely low, so as to be below the noise floor and inaudible. I agree that higher bit depth is beneficial, at 48kHz, but 96kHz+ is not required for audible information - as the ear cannot hear it. The anecdotal evidence here is that no one has ever complained about class D amplifiers - which have vastly greater significant noise at 20kHz+, compared to class A/B. Maybe the experience is that the difference between 16bit and 24bit is the difference heard ?, not the frequency extension. The fact that no hifi press has complained about class D high frequency issues, just shows you that it cannot be heard - so, the effect of MQA is purely the inband changes of its processing, not whether it is lossy high resolution. Regards, Richard. Link to comment
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