The Truth of "Computer Audiophile"

[PeterSt]

I thought your dac was immune to these changes, are you trying to deny those with inferior dacs the pleasure of better sound ?

 

So I wasn't talking about DACs at all. But to answer the question ... with the NOS1 this was so. Not with the isolated "a" version. Nice eh ? that complicated it is. But logical it is anyway, thinking what isolation actually implies or may imply.

[Teresa]

Hi Teresa

You may not remember due to that life threatening disease you are now fighting ,(and I may add, judging by posts in C.A. the old Teresa is very much still there.)

but along with Roch you did a few series of comparison .wav file tests with me some time back.

They included 16/44.1 which with the better version it annoyed you a little less than 16/44.1 normally does , and a couple of tracks from Claire Martin in 24/96 IIRC.

You did of course correctly identify which tracks were which, despite them having identical check sums..

Kind Regards

Alex

 

Hi Alex,

 

I do vaguely remember listening to and correctly identifying music files for you several years ago.

 

Some of my older long-term memory is still there when it is sparked. A lot of long-term memory is lost, not just the words of people I have known in the past, but their faces too. If I could go back and do it again, I would have taken pictures of all my relatives and friends. They are now a blur and fading fast. I do have some memories, but most are of tragic events I would prefer to forget.

 

However, I remember almost nothing of the last few years, not even yesterday. My short-term memory is so bad that I'm lucky no one has to depend on me, I could not even tell you what I watched on TV yesterday, so that must mean nearly nothing new is loaded from short-term to long-term memory.

 

At least I can still speak and type English, it's getter harder so I wonder how much longer?

 

Oh well,

[sandyk]

Teresa

Chin up. You are a gutsy lady, with a lot of people wishing you the best. Yes, it would be nice to have more photos of loved ones stashed away . I wonder how many remember what their mothers looked like when they were younger ?

 

Kind Regards

Alex

[elcorso]

You know, Dennis, I am sick to death of your constant verbal diarrhea trying to prove other people wrong. We've all heard it a hundreds of time before. NO MORE, give us a break !

 

Give it a fucking rest, why don't you !! Go do your own testing, get away from the computer, attend to realspace, listen to music, or something, anything... You really need a better perspective on life, then this obsession with being right.

 

 

edit: Opps, after posting this, I found another page + of posts

 

And, what do you know? I'm not alone in my desire to see Dennis do a major chill out. The people have spoken

 

The problem could be (or is) obsessive temper, because it works in both antagonistic ways: You achieve your goals like a wise person, or, you try forcibly, by insulting and/or doing tantrums like a child. This happens on bad medicated adults or kids. You may know about drugs side effects.

 

The problem is that the whole forum have have to put up this kind of 'attitudes'. I don't want this, the same way I don't want ISIS.

 

Roch

[esldude]

Dennis,

 

Can you carefully read this: https://www.univie.ac.at/nuhag-php/janssen/data/p119.pdf

 

I looked at it, but have not carefully read it. What relevance does it have? We can determine through checksums if the bits were read off properly or not. For ripping purposes it does not matter if the ripping system was marginal and full of jitter or a wonder of accuracy and stability. If both read the same values and created the same ripped file that is all that matters.

 

Audio files contain a bit of metadata, a few bytes to described bit depth, sample rate and number of channels. Then the sample data itself. That is all that is there. There is no where for jitter or noise or anything else to be encoded. You cannot tell from that data if the ripping device was wobbly and marginal or excellent or if some bloke sat at a keyboard typing it in. Once ripped from an optical disc all those optical-mechanical-eletrical aspects have no bearing any longer. They would have a bearing if we were real time playing the disc.

[alfe]

I looked at it, but have not carefully read it. What relevance does it have? We can determine through checksums if the bits were read off properly or not. For ripping purposes it does not matter if the ripping system was marginal and full of jitter or a wonder of accuracy and stability. If both read the same values and created the same ripped file that is all that matters.

 

Audio files contain a bit of metadata, a few bytes to described bit depth, sample rate and number of channels. Then the sample data itself. That is all that is there. There is no where for jitter or noise or anything else to be encoded. You cannot tell from that data if the ripping device was wobbly and marginal or excellent or if some bloke sat at a keyboard typing it in. Once ripped from an optical disc all those optical-mechanical-eletrical aspects have no bearing any longer. They would have a bearing if we were real time playing the disc.

 

Jitter the only devil that you know:)

Sample refer to a set of values in time or space.

Read chapter 3&5

[esldude]

Jitter the only devil that you know:)

Sample refer to a set of values in time or space.

Read chapter 3&5

 

Yes samples and the sample rate tell you what the theoretical perfect playback should be. Nowhere is other timing information embedded in a wav file. What would be the possible mistiming of a wav file typed in from a keyboard?

[Tony Lauck]

Yes samples and the sample rate tell you what the theoretical perfect playback should be. Nowhere is other timing information embedded in a wav file. What would be the possible mistiming of a wav file typed in from a keyboard?

 

I am not familiar with the files in question, but I have investigated other claims of files with identical audio samples sounding different. I can say from personal experience that WAV files made with different software from rips of the same CD may contain identical samples as verified by sample by sample comparisons, and yet have different file contents. As the article did not perform a complete file for file comparison, the fact is that the bits are not the same bits. In addition to the header there are options for how the audio data is stored into "chunks", different layout and even size of metadata tags (if present, some WAV software doesn't support this), etc.. Without the file contents being identical there is no point in proceeding to the next step. Why is this? Because the player programs read all the of file data, not just the samples. Depending on details of the code path, buffer assignments, etc. there can be many reasons for different software execution when the same program is operating on different files. In effect one may be using different player programs, and one would be foolish to ascribe audible (or measured) differences to the ripping process without proper experimental controls.

 

I investigated in some detail a related issue: whether a WAV file that was converted to FLAC and then back to WAV produced two files that sounded the same. Again, what I observed was that the second WAV file sometimes had different content (as verified by an MD5 checksum). The audio samples were identical (as verified by EAC comparison or by differencing in SoundForge). Curiously, after iterated conversion between WAV and FLAC I eventually reached a point with my FLAC conversion software (dBPoweramp) that subequent conversions to WAV were always the same, but not the original WAV file. I never heard a difference between any of the WAV files, so I was unable to investigate further as to why other people might have heard a difference. However, the files were not the same, so I have no problem accepting that they heard differences.

 

In the course of my experimentation, I found a way to take any WAV file and strip off all of the non audio data, creating a "raw PCM" file. This can be played with some software (e.g. SoundForge) or converted back to WAV. This provides a process for taking two WAV files that have different non-audio data and putting them in a standardized format. In the case of the article rip files, this would provide an experimental control if it turned out that the files had different file level checksums but the same audio samples.

 

Unfortunately, most audiophiles and magazine writers lack sufficient in depth understanding of all of the technical factors associated with creation and playback of digital audio files, details of computer hardware and operating systems, etc... While none of this knowledge is essential for getting good sound and enjoying the music, it is absolutely essential if one is trying to conduct scientific experiments, interpret experimental results correctly, or correctly conclude that some occurrence was "impossible" and any results thereof "incorrect".

[Audiophile Neuroscience]

I am not familiar with the files in question, but I have investigated other claims of files with identical audio samples sounding different. I can say from personal experience that WAV files made with different software from rips of the same CD may contain identical samples as verified by sample by sample comparisons, and yet have different file contents. As the article did not perform a complete file for file comparison, the fact is that the bits are not the same bits. In addition to the header there are options for how the audio data is stored into "chunks", different layout and even size of metadata tags (if present, some WAV software doesn't support this), etc.. Without the file contents being identical there is no point in proceeding to the next step. Why is this? Because the player programs read all the of file data, not just the samples. Depending on details of the code path, buffer assignments, etc. there can be many reasons for different software execution when the same program is operating on different files. In effect one may be using different player programs, and one would be foolish to ascribe audible (or measured) differences to the ripping process without proper experimental controls.

 

I investigated in some detail a related issue: whether a WAV file that was converted to FLAC and then back to WAV produced two files that sounded the same. Again, what I observed was that the second WAV file sometimes had different content (as verified by an MD5 checksum). The audio samples were identical (as verified by EAC comparison or by differencing in SoundForge). Curiously, after iterated conversion between WAV and FLAC I eventually reached a point with my FLAC conversion software (dBPoweramp) that subequent conversions to WAV were always the same, but not the original WAV file. I never heard a difference between any of the WAV files, so I was unable to investigate further as to why other people might have heard a difference. However, the files were not the same, so I have no problem accepting that they heard differences.

 

In the course of my experimentation, I found a way to take any WAV file and strip off all of the non audio data, creating a "raw PCM" file. This can be played with some software (e.g. SoundForge) or converted back to WAV. This provides a process for taking two WAV files that have different non-audio data and putting them in a standardized format. In the case of the article rip files, this would provide an experimental control if it turned out that the files had different file level checksums but the same audio samples.

 

Unfortunately, most audiophiles and magazine writers lack sufficient in depth understanding of all of the technical factors associated with creation and playback of digital audio files, details of computer hardware and operating systems, etc... While none of this knowledge is essential for getting good sound and enjoying the music, it is absolutely essential if one is trying to conduct scientific experiments, interpret experimental results correctly, or correctly conclude that some occurrence was "impossible" and any results thereof "incorrect".

 

Hi Tony,

An interesting post.As someone not trained in computer science can I ask some questions.

 

If understandingcorrectly you don’t fully subscribe to the bits is bits argument unless theyare stored and laid out into the same chunks ? My uneducated analogy here beinglike a fragmented hard disc, the bits are the same but in different places? Isthis what you mean that the bits are not the same bits?

 

 

identical samples asverified by sample by sample comparisons, and yet have different file contents

 

different file levelchecksums but the same audio samples.

 

 

I don’t understandthis can you elaborate?

 

the playerprograms read all the of file data, not just the samples. Depending on detailsof the code path, buffer assignments, etc. there can be many reasons fordifferent software execution when the same program is operating on differentfiles.

 

So metadata canaffect playback of the bits (and potentially sound different) ?

 

filesometimes had different content (as verified by an MD5 checksum). The audiosamples were identical (as verified by EAC comparison or by differencing inSoundForge).

 

Different content asin metadata ?

 

If not too personalwhat is your background? Not asking for your ID,lol

 

Cheers

David

 

apologies for words melding together in post.Seems to be happening when text is transferred from OneNotes

[Paul R]

I am not familiar with the files in question, but I have investigated other claims of files with identical audio samples sounding different. I can say from personal experience that WAV files made with different software from rips of the same CD may contain identical samples as verified by sample by sample comparisons, and yet have different file contents. As the article did not perform a complete file for file comparison, the fact is that the bits are not the same bits. In addition to the header there are options for how the audio data is stored into "chunks", different layout and even size of metadata tags (if present, some WAV software doesn't support this), etc.. Without the file contents being identical there is no point in proceeding to the next step. Why is this? Because the player programs read all the of file data, not just the samples. Depending on details of the code path, buffer assignments, etc. there can be many reasons for different software execution when the same program is operating on different files. In effect one may be using different player programs, and one would be foolish to ascribe audible (or measured) differences to the ripping process without proper experimental controls.

 

I investigated in some detail a related issue: whether a WAV file that was converted to FLAC and then back to WAV produced two files that sounded the same. Again, what I observed was that the second WAV file sometimes had different content (as verified by an MD5 checksum). The audio samples were identical (as verified by EAC comparison or by differencing in SoundForge). Curiously, after iterated conversion between WAV and FLAC I eventually reached a point with my FLAC conversion software (dBPoweramp) that subequent conversions to WAV were always the same, but not the original WAV file. I never heard a difference between any of the WAV files, so I was unable to investigate further as to why other people might have heard a difference. However, the files were not the same, so I have no problem accepting that they heard differences.

 

In the course of my experimentation, I found a way to take any WAV file and strip off all of the non audio data, creating a "raw PCM" file. This can be played with some software (e.g. SoundForge) or converted back to WAV. This provides a process for taking two WAV files that have different non-audio data and putting them in a standardized format. In the case of the article rip files, this would provide an experimental control if it turned out that the files had different file level checksums but the same audio samples.

 

Unfortunately, most audiophiles and magazine writers lack sufficient in depth understanding of all of the technical factors associated with creation and playback of digital audio files, details of computer hardware and operating systems, etc... While none of this knowledge is essential for getting good sound and enjoying the music, it is absolutely essential if one is trying to conduct scientific experiments, interpret experimental results correctly, or correctly conclude that some occurrence was "impossible" and any results thereof "incorrect".

 

It's a fairly easy proposition. Take a WAV file, copy it with an OS command. Can the original and the copy of the file ever sound different, given no errors in the copy process?

 

-Paul

[alfe]

Yes samples and the sample rate tell you what the theoretical perfect playback should be. Nowhere is other timing information embedded in a wav file. What would be the possible mistiming of a wav file typed in from a keyboard?

 

You should focus on space, it's CD audio.

[wakibaki]

It's a fairly easy proposition. Take a WAV file, copy it with an OS command. Can the original and the copy of the file ever sound different, given no errors in the copy process?

 

-Paul

 

Hi Paul.

 

Ever? Sure. Take the copy, burn it on a CD, play it on your CDP, even if you match the levels you may be able to tell the difference from the original played on your computer. Hard to key them up in synch. But that's not the point is it? Chances are the playback from the HD is indistinguishable from the CD if you play both on the computer.

 

The idea that the copying process leaves a fingerprint in the copy that is consistently perceptible across a range of playback equipment is absurd. Which is what underlies all these copying claims, because if it doesn't work consistently, what's the point?

[sandyk]

[ Chances are the playback from the HD is indistinguishable from the CD if you play both on the computer.

/QUOTE]

 

A CD played directly from an internal CD drive can sound like shit, in comparison with the same CD after being ripped to HDD/SSD and played directly from System Memory with a good software audio player.

If you can't hear the differences then I feel truly sorry for you. This is what this forum is all about!

[Paul R]

Hi Paul.

 

Ever? Sure. Take the copy, burn it on a CD, play it on your CDP, even if you match the levels you may be able to tell the difference from the original played on your computer. Hard to key them up in synch. But that's not the point is it? Chances are the playback from the HD is indistinguishable from the CD if you play both on the computer.

 

 

The idea that the copying process leaves a fingerprint in the copy that is consistently perceptible across a range of playback equipment is absurd. Which is what underlies all these copying claims, because if it doesn't work consistently, what's the point?

 

I should have added "on the same equipment" - yes, it can certainly sound different on different equipment.

 

-Paul

[wakibaki]

A CD played directly from an internal CD drive can sound like shit, in comparison with the same CD after being ripped to HDD/SSD and played directly from System Memory with a good software audio player.

If you can't hear the differences then I feel truly sorry for you. This is what this forum is all about!

 

There are some subtle things I listen for in music. Sincerity. Honesty. Compassion. Humour. Intelligence. Insight.

 

I can take a guitar off the wall in a shop and tune it, and it'll be in tune with the keyboard when you switch it on. As long as you don't ask me to do it under test conditions.

 

I don't think everything connected with computers is ideal or always designed optimally. Look at USB. It would have been easy to implement a device with flow control, eliminating all question of jitter due to the method of clock recovery. But that's not what we got.

 

I do however, have a very good knowledge of computer architecture in general. Good enough to have written assembly language under x386. I wrote VHDL for glue logic for complex systems employing the PowerPC and for other DSP functions. I know how these things work from the inside out.

 

I don't think I'm missing out on anything.

[Ned Kelly]

Reading this thread reminds me why most men have an internet connection.

 

[PeterSt]

Reading this thread reminds me why most men have an internet connection.

 

Possibly you are posting in the wrong thread then, Kelly.

It would be true though that for under 1500 a nice wide screen monitor plus drooling speakers and PC can be obtained for this and have some satisfaction.

[Miska]

A CD played directly from an internal CD drive can sound like shit, in comparison with the same CD after being ripped to HDD/SSD and played directly from System Memory with a good software audio player.

If you can't hear the differences then I feel truly sorry for you. This is what this forum is all about!

 

Well, it depends. For example HQPlayer can play "directly" from internal (or external) CD drive. But what actually happens is that the CD is being asynchronously ripped to RAM and played from there... So it is essentially exactly same operation as ripping to a file, with the exception that no file ever exists for it.

[alfe]

Yes samples and the sample rate tell you what the theoretical perfect playback should be. Nowhere is other timing information embedded in a wav file. What would be the possible mistiming of a wav file typed in from a keyboard?

 

Should I understand the two's complement as absolute silence:)

[Paul R]

Possibly you are posting in the wrong thread then, Kelly.

It would be true though that for under 1500 a nice wide screen monitor plus drooling speakers and PC can be obtained for this and have some satisfaction.

 

Sigh- Peter, there are far more audiophiles with $1500 systems than with $5000 systems. There are far more audiophiles with $5000 systems than with €20000 systems. If you don't realize that, then at least realize that the $1500 systems may turn into $50000 systems someday.

 

But if those guys keep running into attitudes like yours, that $45000 will get spent on cameras, fishtanks, or some other hobby. That unwarranted arrogance of yours is turning off more audiophiles than informing, educating, or helping people enjoy the hobby.

 

Not very funny either.

 

IMNSHO, and speaking only for myself.

[PeterSt]

Sigh- Peter, there are far more audiophiles with $1500 systems than with $5000 systems.

 

So Paul, is that so. Now, assuming that you didn't wake up with a bad mood (but tell me) then finally we are getting somewhere with my stupid suggestive thread and subject. Listen, learn, read on.

If you like of coure, no obligations.

 

I know of NONE.

 

Still, in here, you are now as far as explicitly telling me that I must have it all wrong. Good thing, because that is what this thread is for. I can't believe it, and you, as the representative of CA, are now telling me and everybody different.

Sadly, to me this tells something. And NO, this is not personal at all. No way.

 

We tried to define "audiophile" to some degree, and ended up with someone who is eager to improve his audio system. Btw, this was done on my initiative, just to be sure that it is not about the $ really.

That you out there do this with under 1500 systems is fine. Still though there must be a difference, because I still know NONE. Okay, maybe this doesn't tell all, but it has to tell something. At least about how "you" and me may never understand each other (and remember, "you" between quotes because it is not personal).

 

You could say that I attract people with 1500+ systems because I coincidentally sell a DAC which is above that, but I don't look at it that way, plus there are 1000s only using the software, as how it originally was intended (to have a living on its own).

Otherwise about all of those who obtained the DAC where 72 euro XXHighEnd users first, and they weren't aware of any crazy DAC. And I think I know from 100% all of them what systems they apparently had to begin with.

 

But I see. It got as far as I am now destroying our youth who were just climbing out of their iPods.

No, you must be having a strange mood. That btw, is personal.

 

Peter

[Paul R]

Well, I know of hundreds - personally. Perhaps you are just not looking in the right place?

 

Of those, many are people who are (relatively) young and not making huge salaries. They don't have as much discretionary funding as, say, you or I do. So yeah, to them, putting CD quality tracks on their phones and using a $300 set of headphones is just about the best they can do. Others spend $600 on an AVR and $900 on speakers, then stream music with Apt/X.

 

So yeah, if you don't know any, then you are simply not looking.

 

And to use your example, what if someone uses $79 XXHighEnd on a $200 PC (available today from Best Buy) feeding into a $600 receiver and playing to a set of $599 or less speakers? Surely they can call themselves audiophiles. If it were I on that budget, I would surely save money for music more than over extending on gear, and still be an audiophile.

 

So yes, saying you opinion or my opinion is better or worse than someone else's based only on the cost of their gear is *ridiculous*.

 

As has been said before, once one knows what to listen for, one can usually hear it, even on $100 Pioneer speakers, driven by a $300 integrated amp, and fed by an iPhone.

 

Would I rather have the more expensive gear? In most cases, yes. But it is making the most of what you have that defines an audiophile to me.

 

-Paul

 

 

 

 

So Paul, is that so. Now, assuming that you didn't wake up with a bad mood (but tell me) then finally we are getting somewhere with my stupid suggestive thread and subject. Listen, learn, read on.

If you like of coure, no obligations.

 

I know of NONE.

 

Still, in here, you are now as far as explicitly telling me that I must have it all wrong. Good thing, because that is what this thread is for. I can't believe it, and you, as the representative of CA, are now telling me and everybody different.

Sadly, to me this tells something. And NO, this is not personal at all. No way.

 

We tried to define "audiophile" to some degree, and ended up with someone who is eager to improve his audio system. Btw, this was done on my initiative, just to be sure that it is not about the $ really.

That you out there do this with under 1500 systems is fine. Still though there must be a difference, because I still know NONE. Okay, maybe this doesn't tell all, but it has to tell something. At least about how "you" and me may never understand each other (and remember, "you" between quotes because it is not personal).

 

You could say that I attract people with 1500+ systems because I coincidentally sell a DAC which is above that, but I don't look at it that way, plus there are 1000s only using the software, as how it originally was intended (to have a living on its own).

Otherwise about all of those who obtained the DAC where 72 euro XXHighEnd users first, and they weren't aware of any crazy DAC. And I think I know from 100% all of them what systems they apparently had to begin with.

 

But I see. It got as far as I am now destroying our youth who were just climbing out of their iPods.

No, you must be having a strange mood. That btw, is personal.

 

Peter

[PeterSt]

Paul, let's just start over again please.

 

I see no need for a silly debate. The thread has been there and has come to an end as how I see it. But then there was Kelly's post which I could not understand at all and I responded to him in a way which has nothing to do with the subject at all. Read again (now you know it). Next though you see a 100 negatives in my post and start the subject again.

No need to.

 

Is that OK ?

 

Peter

[Jabs1542]

Paul,

 

I have many friends with the "$1500" type systems and I use their music selections as my indicator to determine if they have audiophile potential. So far, and this is close to 20 people, that answer has been "no". These folks that I know are listening to highly compressed Pop music usually in MP3 format. They play music for convenience usually in the background. As I asked each of them, not a single one of them ever; a) sits down and listens to an album, nor do they b) get excited about a new piece of music.

 

You may know some "$1500 system audiophile" folks but so far all of the folks I know who have "caught the audio bug" are well above $3K plus for their system with well over $500 tied up in music alone.

 

I think the difference between you and Peter, and me, is the point of entry for this hobby (not just a dollar figure but the commitment to actually listening to music).

[Tony Lauck]

Hi Tony,

An interesting post.As someone not trained in computer science can I ask some questions.

 

If understandingcorrectly you don’t fully subscribe to the bits is bits argument unless theyare stored and laid out into the same chunks ? My uneducated analogy here beinglike a fragmented hard disc, the bits are the same but in different places? Isthis what you mean that the bits are not the same bits?

 

 

 

 

 

I don’t understandthis can you elaborate?

 

 

 

So metadata canaffect playback of the bits (and potentially sound different) ?

 

 

 

Different content asin metadata ?

 

If not too personalwhat is your background? Not asking for your ID,lol

 

Cheers

David

 

apologies for words melding together in post.Seems to be happening when text is transferred from OneNotes

 

I subscribe to the goal that "bits should just be bits". I believe this is something that this is an appropriate goal for digital audio systems to approach. I do not believe that this is generally achieved in practice. It is certainly not the case based on my limited observations of audio products. I worked for a major computer manufacturer for over 25 years. We were constantly pushing the limits of technology from the device physics level at our chip plant up to applications programs. I got to see the ugly reality of how things really worked in practice, sometimes listening to people explain why their projects were late and over budget and sometimes having to defend the problems of my own group in this regard.

 

I believe that people who discuss their experiments should have some idea of what might go wrong. It is not sufficient to work at the level of marketing brochures if one is serious. I learned this in a high school physics lab where we used a long pendulum in a stairwell to measure the acceleration of gravity, timing it with an AC powered electric stop watch. My lab partner and I got incorrect and inconsistent results, with our computed "acceleration of gravity" varying as a function of time of day. We repeated the measurements several times and turned in our honest work and were rewarded with a B- grade. This pissed us off, so we had some more discussions with the instructor and repeated the experiments. Eventually, we traced the problem down to variance in the power line frequency and went with the instructor to the local power plant where we compared strip chart reports of the power line frequency with our measurements. We had been using gravity to measure the power grid, not the power grid to measure gravity. We were rewarded with the grade of A+, but in hindsight I remained disappointed, because most of the students in the class who got the "correct" results using the same equipment had almost certainly cheated. The lesson here is that experimenters had better know how their apparatus works. (A year or so back there was a flap at CERN about a preliminary result that neutrinos had been observed going faster than light. This was eventually traced down to "experimental error".)

 

In the case of audio files, one needs to look at all the bits in the file, not just the ones that are said to be "important", before one can reach any kind of valid conclusion as to whether or not bits are just bits. The fact that the author of the article didn't provide this information is sufficient for me to conclude that he was not a suitable conduit of reliable information.

 

Whether non-data bits in a file affects playback is not the point. The existence of uncontrolled variables invalidates the entire experiment, especially if there are readily available control mechanisms (such as file level checksums) that could easily be used. It could be that the file checksums were identical and hence the files had the same "contents". However, my experience with software (and supported by my experiments with dBPoweramp FLAC conversion) is that it was more likely than not that the files were different.