High Resolution Audio: Does It Matter?

[tomelex]

this is just some interesting info I think fits here

 

[Sal1950]

Yea Mark had it nailed right on what should be defined and marketed as HDA.
He then got kicked out of his seat on the CEA/CTA board for his efforts.
He was told "off the record" that his position was " bad for commerce".

 

[Thomas savage]

Yea Mark had it nailed right on what should be defined and marketed as HDA.
He then got kicked out of his seat on the CEA/CTA board for his efforts.
He was told "off the record" that his position was " bad for commerce".

 

[Sal1950]

Tisk Tisk, have you no heart?

 

[Thomas savage]

That songs all about having hart in the face of life's knocks. Ignoring the humans nonsense and raising high, back on top.

I thought it appropriate, if you listen to the words rather than just think the title is about being flippant. That's not what the song is saying... That's not what I was saying.

 

[March Audio]

I am unsatisfied with your answer. 24 bit systems don't have a volume knob? Mine does.

1. There are no stairsteps.

2. 16bit is linear (low distortion) - we stretch and compress it all the time (linearly) with the volume control.

3. The littlest bit is said to be as linear at the rest of them when we have proper dither.

So. What's the deal?

Indeed hence why 60dB below FS is probably a more realistic range in most listening

 

[Sal1950]

That songs all about having hart in the face of life's knocks. Ignoring the humans nonsense and raising high, back on top.

I thought it appropriate, if you listen to the words rather than just think the title is about being flippant. That's not what the song is saying... That's not what I was saying.

Ah, so you do have a heart after all. I'm elated. LOL

 

[SoundAndMotion]

Hi Ray,

I’m surprised no one helped with this post.

Yes, if you arbitrarily assign a value of 6dB per bit.

Do we really do that in practice?

Yes, we do this, but it is not arbitrary. Every time you add a bit, you double the number of possible values, and therefore you either double the max value, or more likely, you halve the smallest value… either way you change by a factor of 2. Back to this “2” in a moment.

“Decibels” always requires a ratio (x1/x0), always with a specific, defined reference, x0.

dB = 20*log10(x1/x0) for volts, for example.

For dBFS, the reference is “full scale”, the maximum possible value, and all smaller values are negative, because the log of a ratio smaller than one is negative. For dB SPL, the reference is a sound pressure level of 20 micro Pascals, which is approx. the human threshold of hearing at 1kHz.

So the factor of 2 now means (with a little hand-waving, if you’ll allow) that you have increased the dynamic range by 20*log10(2) = 6.0206, or about 6.

Don't we have a volume knob which we rotate to assign however many (even fractional) dB of in-room SPL to the so-called 96dB for the 16 bits on the disc?

Yes, but…

If I turn the knob a little more to the right, for peaks of 116 dB in room, playing redbook, do I not get 7.25dB per bit from a 16bit source? (16 x 7.25 = 116)

If I play a 24 bit source at that same 116db peak in room, did I not select 4.83 dB per bit?

24 bit = 144dB at 6dB per bit, 16 bit = 144dB at 9dB per bit.

Straighten me out.

The volume control controls the gain of the amp. This is a fixed multiplier; it does not expand or compress the dynamic range of your recording. If you increase the loudest sound, you also increase the quietest sound by the same gain factor, and vice-versa for a decrease. This shifts the range, even by fractions of a dB. Perhaps you have shifted the loudest beyond the threshold of pain or the quietest down into the noise, but your (theoretical) dynamic range is constant. If you started with 96 dB range, you could have it be 50 to 146 dB SPL or -36 to 60 dB SPL.

Before anyone jumps on this simplified explanation, keep in mind it was simplified.

Cheer, SAM

 

[DonH56]

For reference, with a sinusoidal input, the SNR of an ideal N-bit ADC or DAC operating with a full-scale signal is 6.021*N+1.76 dB. The value is different if you use an input signal other than a sine wave. The SFDR, i.e. range from full-scale to the noise floor, is ~9*N (approximate as there is no closed-form solution).

Actual dynamic range does change with the volume control due to (typically) changing distortion components and fixed noise floor.

FWIWFM - Don

 

[Fitzcaraldo215]

this is just some interesting info I think fits here

Waldrep makes some really excellent points. And, he might help to clear up much confusion on the subject. The key cautionary notes for listening comparisons between hi rez and RBCD relate to the provenance of the recording listened to. To really hear the difference, it must be hi rez throughout the chain, starting with the recording. Even hi rez remasters from analog will not do. (That was one flaw in Meyer-Moran.). And, as Mark points out, that is often tough to do, especially with pop recordings. So, many user listening anecdotes about not hearing a difference with hi rez may be flawed by this.

What he did not say is that the overwhelming majority of true hi rez recordings are classical, especially from SACD. There are thousands of those, most also in Mch, mainly from small European labels like BIS, Channel Classics, Harmonia Mundi, 2L, etc. AIX, of course, on BD is a good choice for hi rez, although much of their catalog, containing a lot of pop, does not appeal to me all that much. 2L, featuring a lot of obscure Scandanavian music, is also not a favorite of mine.

Also, the question of comparing the RBCD layer with the stereo DSD layer on hybrid SACDs has its technical issues, like level matching. But, you will find that the classical labels use only one hi rez master for both stereo versions, with final downconversion for the CD layer.

BIS appears to offer the largest catalog of hi rez on SACD, and I enjoy their releases a lot. But, they switched format/resolution a few times. Their initial hi rez releases were done in DSD. Then, they switched to 44k/24 for a long period. And, for the last few years, they have used 96k/24 exclusively. But, even the 44k/24 releases sound generally quite good to me in Mch. I am also generally happy with Mch BD sound at 48k/24. I have also listened to some DSD256 and some DXD, with the rapidly dimishing sonic returns you might expect vs. more main stream hi rez at lower sampling rates. Although, easily the best recording I have heard to date was done at DSD256. However, its excellence might be due more to special care in miking and engineering rather than ultra resolution.

So, the hi rez shell games Mark alluded to are a rarity in classical music, except for the remasters from analog. I do have a lot of industry insider info from a good friend, who is a Grammy-winning recording engineer currently doing a lot of work for Channel Classics, a great label in hi rez Mch classical.

 

[Blumlein 88]

I drove from Charlotte to Carrboro today for the inspection of my new place there; 2.5 hours. I have iTunes automatically compress files to 256kbps when transferring to my iPhone. Being the old dog I am, there were a lot of 60s/early 70s recordings on there. They sounded fine. Then on came Edith and the Kingpin from Herbie Hancock's River: The Joni Letters. This is an amazing DDD recording. And even at 256kbps, even through my bog-standard Ford audio system, it was still amazing. Really stood out from those older recordings. It's about the recording, gentlemen. Always has been.

Tim

Talk about not being good for commerce, what kind of attitude is this Tim? The grand children of audio boutique designers are suffering if everyone has this attitude. Think of the children before spreading this idea about in public forums PLEASE.

 

[NorthSky]

Lol

 

[Fitzcaraldo215]

I think it is interesting to reread this thread, starting with Amir's paper at the beginning in light of the recently released Reiss paper on hi rez discussed here:

http://audiosciencereview.com/forum/index.php?threads/aes-meta-analysis-on-audibility-of-hi-res.604/

Amir's paper predates the Reiss paper, but I think you will find the strikingly similar conclusions fascinating. By hindsight, I also have to pat myself on the back for reaching similar conclusions on my own with my own imperfect listening skills via less than scientifically rigorous methods. But, I am not alone. Saner heads than my own have been on the right track for a long time, as it seems, including Amir.

As is clear, hi rez is not a breakthrough, it is just an improvement. Whether it is even audible and worthwhile or not to you with your own choice of music formats is entirely up to you. Marketing hype for hi rez audio is no greater than for anything else. But, the existence of hype does not perfectly assure that the opposite must therefore be true.

What really takes me by surprise is my impressions of other threads in the web sphere I have surveyed, as reactions to the Reiss paper have exploded. I have very distinct objectivist leanings, one reason for being active in this forum. But, it is becoming quite clear that the ostensibly "objectivist" forums are so loaded with their own cynical, contrarian biases that they cannot even read or interpret a very well done scientific paper, like Reiss', with any degree of objectivity. I have no love for total subjectivists, but extreme "objectivists" are not necessarily any better, in my view.

The best balance is right here in this forum, IMHO.

 

[amirm]

What really takes me by surprise is my impressions of other threads in the web sphere I have surveyed, as reactions to the Reiss paper have exploded. I have very distinct objectivist leanings, one reason for being active in this forum. But, it is becoming quite clear that the ostensibly "objectivist" forums are so loaded with their own cynical, contrarian biases that they cannot even read or interpret a very well done scientific paper, like Reiss', with any degree of objectivity. I have no love for total subjectivists, but extreme "objectivists" are not necessarily any better, in my view.

Amen to that.

 

[krabapple]

Well, we've known for awhile, at least where Amir is posting, that well-trained listeners can consistently differentiate hi rez from CD.

Huh? Define 'consistently'. And define 'well-trained' in a way that does not recurse back to 'passes a blind test'.

Now we have a study confirming it statistically, and even a theory of what these well-trained listeners might be hearing: Filtering artifacts. Pre-ring.

Which, if so, imply less than 'perfect' preparation and playback of an RBCD.

 

[krabapple]

You will get nowhere with a PS3 rip of an SACD because you still have the PCM vs. DSD issue.

Ah, have we proved that THAT is audible now, too?

Officially or not?

And, as the opening post of this thread describes, we do not "know" anything for sure. It is perceptual. We know how RBCD and hi rez measure, but there are still many open questions as to audibility. Given the uncertainty of all that, you just have to reach your own conclusions based on listening, unless you want to conduct your own comprehensive double blind tests with a large number of subjects and samples. I do not need to do that. I have reached my own conclusions which are good enough for me, if no one else.

And what conclusion do you think is defensible, from a sighted A/B? How many caveats would you attach?

 

[Fitzcaraldo215]

Ah, have we proved that THAT is audible now, too?

Officially or not?






And what conclusion do you think is defensible, from a sighted A/B? How many caveats would you attach?

1. Not surprisingly, you missed the point once again. ceedee was suggesting that if he had a rip of an SACD done on a PS3, he would be able to tell if the hi rez stereo program, which is in DSD, had used the same master as the CD layer, which is in PCM. My point was that was not possible, DSD vs. PCM being one of the issues. I said nothing in that post about audibility or in praise of DSD. Got it?

2. I said nothing about sighted vs. unsighted listening comparisons in making your own determination for your own use. Unsighted comparisons are to be preferred, of course. I was referring to doing your own personal comparisons vs. doing a large scale scientific study on many test subjects. That would of course require careful double blind testing to have any validity.

But, you seem to be on some sort of mission, tirelessly and tiresomely saving the world from something or other, from me, perhaps? But, it is not helpful to put words in my mouth or twist my meaning, then joust with that distortion which you, yourself, have created in your crusade.

I feel your pain about not being able to hear the difference between hi rez and CD, which have differences measurable by traditional audio measurements. But, apparently, per a different thread, you can hear the difference between WAV and FLAC versions of the same music file, which have no scientifically provable differences in their audio measurements. More power to you and enjoy!

 

[krabapple]

I feel your pain about not being able to hear the difference between hi rez and CD, which have differences measurable by traditional audio measurements.

Who ever said there were no measurable differences between the formats?
(NB: Imaginary people don't count).

But, apparently, per a different thread, you can hear the difference between WAV and FLAC versions of the same music file, which have no scientifically provable differences in their audio measurements. More power to you and enjoy!

Apparently.


Btw you forgot to answer this:
And what conclusion do you think is defensible, from a sighted A/B? How many caveats would you attach?

 

[ceedee]

1. Not surprisingly, you missed the point once again. ceedee was suggesting that if he had a rip of an SACD done on a PS3, he would be able to tell if the hi rez stereo program, which is in DSD, had used the same master as the CD layer, which is in PCM. My point was that was not possible, DSD vs. PCM being one of the issues. I said nothing in that post about audibility or in praise of DSD. Got it?

Oh sure you can tell if they're from the same master. Why wouldn't you be able to? But that's not the point; comparing SACD layers is invalid … way too many possible variables. As we covered previously.

Oh and Krabapple was being sarcastic in the FLAC vs. WAV thread … obviously. He doesn't claim to hear differences.

 

[krabapple]

Waldrep makes some really excellent points. And, he might help to clear up much confusion on the subject. The key cautionary notes for listening comparisons between hi rez and RBCD relate to the provenance of the recording listened to. To really hear the difference, it must be hi rez throughout the chain, starting with the recording. Even hi rez remasters from analog will not do. (That was one flaw in Meyer-Moran.).

Therefore a flaw in every positive (or negative) review ever posted about an analog-staged hi rez release , that attributes the improvement/flaw to hi rez itself, since the dawn of hi rez. Whose first releases were , overwhelmingly, sourced from analog (and whose most anticipated/popular releases still are).

And, as Mark points out, that is often tough to do, especially with pop recordings. So, many user listening anecdotes about not hearing a difference with hi rez may be flawed by this.

D'ya think?

BIS appears to offer the largest catalog of hi rez on SACD, and I enjoy their releases a lot. But, they switched format/resolution a few times. Their initial hi rez releases were done in DSD. Then, they switched to 44k/24 for a long period. And, for the last few years, they have used 96k/24 exclusively. But, even the 44k/24 releases sound generally quite good to me in Mch. I am also generally happy with Mch BD sound at 48k/24. I have also listened to some DSD256 and some DXD, with the rapidly dimishing sonic returns you might expect vs. more main stream hi rez at lower sampling rates.

Indeed, you might *expect*. Good word, that.

Although, easily the best recording I have heard to date was done at DSD256. However, its excellence might be due more to special care in miking and engineering rather than ultra resolution.

(sigh) isn't it always the case? Pesky *reality* pooping on the hi rez parade. What's a hi rez fan to do?

So, the hi rez shell games Mark alluded to are a rarity in classical music, except for the remasters from analog.

The shell game is thriving in all sectors, as long as people assume that 'this sounds better to me...because it's hi rez!' As the industry and its cheerleaders have always encouraged them to do. Including the enablers who say 'listen and decide for yourself', as if that was a valid way to decide whether hi rez 'matters'.