What sampling / bit rate would equal vinyl?

[claytonJ2]

OK, yes, I'm posing a controversial question, but honestly and with the best of intentions. I recognize that there's no quantification of either medium that will be fair to both formats. That at some point you have to call in a cognitive expert to weigh in on what the ear is capable of hearing and what can be perceived. To even pose such a question is like bringing up politics or religion. Vinyl junkies swear there is a difference: It's the only medium that contains actual music.
Adherents of digital encoding of audio point out all the many benefits and practicalities and the emergence of better and better technologies. Plus, most new vinyl contains music that was processed digitally at some point anyway, so they might say that fans of vinyl are deluding themselves.
But I'd like to put such things aside and ask if there has ever been a study to quantify what is required to reproduce audio digitally what is possible with analog. For that matter, how do either compare to actually being there? Can digital one day exceed vinyl or has it already? What's the bitrate of the human ear?

 

[Phelonious Ponk]

OK, yes, I'm posing a controversial question, but honestly and with the best of intentions. I recognize that there's no quantification of either medium that will be fair to both formats. That at some point you have to call in a cognitive expert to weigh in on what the ear is capable of hearing and what can be perceived. To even pose such a question is like bringing up politics or religion. Vinyl junkies swear there is a difference: It's the only medium that contains actual music.
Adherents of digital encoding of audio point out all the many benefits and practicalities and the emergence of better and better technologies. Plus, most new vinyl contains music that was processed digitally at some point anyway, so they might say that fans of vinyl are deluding themselves.
But I'd like to put such things aside and ask if there has ever been a study to quantify what is required to reproduce audio digitally what is possible with analog. For that matter, how do either compare to actually being there? Can digital one day exceed vinyl or has it already? What's the bitrate of the human ear?

You seem to understand the issues. Given that understanding, you must know that there is no answer to your question, and that it is likely to ramble on with often-repeated arguments, eventually turn sour, and end with a locked thread. So why not play your hand up front and be done with it? What do you think?

My ears tell me that given exactly the same master of the same recording, the only thing redbook (16/44.1) misses is the noise, distortion and designed limitations of vinyl. The Nyquist-Shannon sampling theorem supports my ears, theoretically (in the scientific, not philosophical sense) , anyway. Others believe that vinyl contains an immeasurable quality that brings it closer to live music than digital ever gets. We all hear what we hear and believe what we believe. As to your other questions:

has (there) ever been a study to quantify what is required to reproduce audio digitally what is possible with analog

There have not only been studies that quantified what is required to reproduce audio digitally, audio has, in fact, been reproduced digitally. What is possible with analog is long-established and has been measured and studied ad-infinitum. It is only what is heard, but cannot be measured, that is controversial. Science will not help you there; blind listening tests won't even be helpful as the differences between digital and vinyl are not subtle, it is the subjective quality of those differences that is in question.

how do either compare to actually being there?

How do they compare to being where? This subject has been beaten pretty hard around here. Is the "there" in question some imagined seat in the hall where a live recording took place? Or is it the very different positions of the various microphones that captured the music in that hall? Is "there" the mixing, processing and remastering after the recording? Or is it the recording itself, which in almost invariably sounds radically different from what human ears would hear from any seat in the hypothetical house? The recording that would reveal what you're hoping to reveal is exceedingly rare, if in existence outside of bad bootlegs, audiophile noodlings and the odd binaural recording. No recording engineer worthy of minimum wage would try to capture a professional live recording with a stereo mic from a single seat in the house. "There" isn't here.

Can digital one day exceed vinyl or has it already?

See all that subjective stuff above.

What's the bitrate of the human ear?

What's the wordlength of the human imagination?

Tim

 

[JackD201]

Analog can theoretically be quantized. I believe some work has been done on this at the University of St. Andrews. The difference according to the paper was not so much due to dynamic range and resolution but rather the noise shaping that occurs depending on stylus shape mainly and a host of other factors on the one end and algorithms and such on the other. Interesting stuff.

 

[Phelonious Ponk]

Analog can theoretically be quantized. I believe some work has been done on this at the University of St. Andrews. The difference according to the paper was not so much due to dynamic range and resolution but rather the noise shaping that occurs depending on stylus shape mainly and a host of other factors on the one end and algorithms and such on the other. Interesting stuff.

I'd love to see that paper, Jack. Where did you see it? Title?

Tim

 

[Vincent Kars]

St Andrews, Jim Lesurf? :
http://www.audiomisc.co.uk/HFN/goodresolutions/page1.html
http://www.audiomisc.co.uk/HFN/LP1/KeepInContact.html

 

[fishnchips]

People often refer to "vinyl" indiscriminately, whilst forgetting that the vast majority of vinyl nowadays is cut from digital masters. Analog magnetic tapes deteriorate physically and magnetically over time, with magnetic deterioration an intrinsic property of the magnetic particles used in tapes. There is also the issue of copying, with each generation of copied master tapes being inferior to the previous one. The latter is inevitably true of direct-cut vinyl as well. Therefore any discussion of "digital vs. vinyl" must not include vinyl cut from digital masters, which would be prima facie silly.

 

[MylesBAstor]

St Andrews, Jim Lesurf? :
http://www.audiomisc.co.uk/HFN/goodresolutions/page1.html
http://www.audiomisc.co.uk/HFN/LP1/KeepInContact.html

That reminds me of the argument of why bumble bees can't fly

 

[Vincent Kars]

According to Shannon-Nyquist your sample rate should be the double of the highest frequency. Vinyl can contain signals up to 25 kHz (but higher values are reported) so 44.1 kHz is probably a bit at the low site.
When doing the AD conversion any signal in excess of half the sample rate generates an error.
The input should be band limited.
High sample rates allow to use a smoother filter.
Low sample rates like 44.1 kHz forces you to use the same steep filtering (brick wall) as in the first generation CD players.


Vinyl can have a dynamic range of 70 dB (but often limited to 50 dB)*so 70/6=12 bits should do.
But you need some headroom and in case of post-processing it is beneficial to have a 24 bit format.

 

[fishnchips]

Vinyl can have a dynamic range of 70 dB (but often limited to 50 dB)*so 70/6=12 bits should do.

This way a pianissimo at, say, -50 dB below peak will be encoded at 6-bit accuracy. Do you think this is good enough?

 

[Vincent Kars]

Theoretical 12 bits will do to cover the dynamic range.
But I won't recommand it.

 

[Phelonious Ponk]

That reminds me of the argument of why bumble bees can't fly

That reminds me of the typical, baseless dismissal of evidence one sees when the science is unacceptable within the belief system.

Tim

 

[mep]

This thread was destined for trouble from the start. But I want to say this about that: Digital has a superior dynamic range capability that increasingly is not being utilized to anywhere near its full capabilities. What good is having a theoretical dynamic range of 98dB if you aren’t using half of it? It’s kind of like giving your great-grandmother a Ferrari to drive to church. I think some people automatically assume that because digital is capable of 98dB of dynamic range that it’s there to be heard on every recording. It’s not people. The real question that needs to be asked is what is the average dynamic range of CDs? That would be interesting to know.

Of course vinyl has a higher noise floor than digital. But guess what? You can hear below that noise floor and I think all of that information gets thrown out in the dynamic range calculations. My experience is that the average LP sounds like it has more dynamic range than the average CD. Vinyl will never be as quiet as CD or tape, but it doesn’t stop it from sounding like it has more dynamic range than the average CD. Much has been written lately about the compression wars going on to make every digital recording sound as loud as possible so it jumps from whatever source you are listening to. Thankfully LPs aren’t getting that crap treatment in one of the ironies of this hobby.

So, digital lovers can be smug with their touted superior dynamic range capability over vinyl, but it doesn’t change how compressed modern recordings are. Nor does it change the fact that mastering for LP are being done to maximize the dynamic range. And for those of you that strictly listen to the digits and have no analog rigs and LPs to play, you are probably relying on some distant memories of how records sounded on whatever rig you had at the time. Memories can be deceptive. I listen to digital often and I do enjoy it more now than I ever have before. But you won’t hear me crowing about how digital sounds so much more dynamic than vinyl or tape. It does win the “quiet” war though.

Mark

 

[amirm]

I am not an LP guy. Last time I heard a comparison of CD vs LP was in 1982-1983 and the LP sounded better, leaving this poor engineer flabbergasted and embarrassed as he had talked up the advantages of digital . Still, I threw out all of my records and stayed with digital as I put higher value on convenience than extra fidelity.

I was looking for some other point to raise here but by accident landed on this guy's video showing an example of LP's frequency response:

Putting aside perceptual issues, clearly LPs frequency response is quite high. Tim earlier said this is about what we can't measure but may be able to hear. In this example at least, we *can* measure a difference. So the question is the opposite: how the difference we can measure, results in audible differences.

On that front, I have always been disappointed that no one has attempted to model an LP system. If we had such a thing, we could apply it to our digital system and then compare and see if the LP sound is due to non-linear transformation or some limitations of digital we don't yet understand. Lack of commercial interest in answering such questions means that we will probably never have data and analysis we can use to probe further in this area.

 

[microstrip]

(...) Putting aside perceptual issues clearly LPs frequency response is quite high.

Amir,
Well, the main question of this thread is about a perceptual issue. Putting it aside seem strange ...

Curiously that no one noticed a key sentence in the first post "For that matter, how do either compare to actually being there?" Most of our disagreements come from different interpretations of being there. Is being there being in the life performance or in the control room?

 

[amirm]

I hear you . The problem with perceptual issues are harder to deal with than not. For the sake of argument, let's assume we want to match LP's specs. Let's figure out what that looks like. The result may be an overdesigned system but then we can scale back. No?

 

[jazdoc]

A thought provoking post which has led me to compare audio to my daily work as a radiologist. Let me explain...

A standard analog chest radiograph is ~ 1,000,000 x 1,000,000 pixels, dwarfing the amount of data in state of the art digital radiographs which are 1024 x 1024. Now when the stars are aligned, i.e. a thin patient who takes a good inspiration, who is well positioned by a superb technologist utilizing optimal technique, the results are spectacular and better than digital imaging. However, this happy confluence of circumstances rarely occurs. Digital radiography has two huge advantages: 1) it is much more convenient and 2) you can manipulate the images and optimize information to assist diagnosis. Despite sacrificing 99%+ of the data, I prefer digital imaging.

Analogizing to audio...It is truly a rare event when an inspired artist with great material has a technically proficient performance captured by a great engineer/producer to create an analog sonic masterpiece. Like radiology, digital audio is more convenient. What our current media/players lack is the ability to readily manipulate the data. If your recording is strident, there is no way to dial back the high frequencies, if the piano is too far into the background, you can't bring 'em forward. And as others have noted, digital recordings rarely utilize the full dynamic range potential of the medium. Now I understand from the artists' point of view, they need control over their product. Therefore it is unlikely an accommodation will be reached that would allow the end user to manipulate the data to suit their tastes. For me, that is the great unfulfilled potential and frustration of digital music.

 

[microstrip]

I hear you . The problem with perceptual issues are harder to deal with than not. For the sake of argument, let's assume we want to match LP's specs. Let's figure out what that looks like. The result may be an overdesigned system but then we can scale back. No?

Ok. But what will be the type of specs you are going to discuss and the method to analyze them?
BTW, during your stay at Harman did they disclose you any clue about the type of measurements and analysis they carry during amplifier development?

 

[microstrip]

A thought provoking post which has led me to compare audio to my daily work as a radiologist. Let me explain...

A standard analog chest radiograph is ~ 1,000,000 x 1,000,000 pixels, dwarfing the amount of data in state of the art digital radiographs which are 1024 x 1024. Now when the stars are aligned, i.e. a thin patient who takes a good inspiration, who is well positioned by a superb technologist utilizing optimal technique, the results are spectacular and better than digital imaging. However, this happy confluence of circumstances rarely occurs. Digital radiography has two huge advantages: 1) it is much more convenient and 2) you can manipulate the images and optimize information to assist diagnosis. Despite sacrificing 99%+ of the data, I prefer digital imaging.

Jazdoc,
You are forgetting to tell us a very important technical detail that is relevant to the audio metaphor - the dynamic range of digital radiology is much wider than film radiology. This detail can make a lot of difference, as well as the intensive preprocessing that is currently carried by modern instruments.

 

[amirm]

I am not an LP guy so someone else has to provide the specifics. Once there, we can easily compute the sampling rate as Vincent tried to do earlier.

On your second question, no, most of the material was related to speakers and room acoustics. You can read about some of the analysis they do currently in the the Model 53 amplifier: http://173.203.156.112/Uploads/File...Technology Background V5 04032010_5.17.10.pdf. Mentioned in there are differential tests and blind/subjective.

 

[jazdoc]

Jazdoc,
You are forgetting to tell us a very important technical detail that is relevant to the audio metaphor - the dynamic range of digital radiology is much wider than film radiology. This detail can make a lot of difference, as well as the intensive preprocessing that is currently carried by modern instruments.

But the analogy holds...we oft times do not take advantage of the available dynamic range in imaging. The pre-processing is analogous to what happens in the recording studio. I was alluding to what happens after the image and audio is submitted in 'final' form. As an end user of imaging, I can significantly manipulate the data (limited only by the richness of the original content) while as an end user of audio, my ability to post-process is limited once I get beyond the colorations inherent in any audio equipment.