Can two audio files with the same checksum, played from the same devices, sound different?

[wgscott]

I don't get this discussion. No one seriously argues that the 2 files are different. That's just not a plausible argument.

 

Two do, which is a lower bound.

 

The question then becomes, can they sound different, and if yes, how?

 

Well John Swenson has demonstrated (and measured) that different playback software installed in the same HW setup can result in different amounts of ground plane noise being generated when playing back the same file. Ground plane noise can intefere with transmission of audio and thereby effect the resulting sound in playback. So this could be an explanation for some of the differences heard by users when playing back files, even when the data is identical, or perceived differences between lossless compressed and uncompressed.

 

But I believe the original question here assumes that everything in the playback chain is the same - HW and Software - if that is so, then no I don't believe they can sound different, because they are identical.

 

Yep. That was the point.

[wgscott]

Is there a who cares choice.

 

Yes, but it is only visible to people who deploy correct punctuation.

 

Here is a thought: If you aren't interested in the topic, don't click on the link to the thread.

[elcorso]

John Swenson, whose day job I believe involves data storage hardware design, mentioned that he thinks it's possible for jitter to be in effect preserved in a stored file, because stored binary 1s do not all have precisely the same levels (but they're all high enough to be 1s), and neither do all stored 0s have precisely the same levels (but they're low enough to be 0s).

 

However, John could not think of a mechanism (other than fragmentation) resulting in a difference between two bit for bit identical files that would be affected by history prior to the time of the immediately preceding storage on disc/SSD.

 

So I suppose if practical for you, it would be a nice idea to rip with the best quality, lowest noise hardware you have available for the purpose. Couldn't hurt.

 

Can two audio files with the same checksum, played from the same devices, sound different?

 

Yes.

 

Please read Miska comments on the exaSound DACs thread regarding recording embedded jitter!...

 

Roch

[kumakuma]

Can two audio files with the same checksum, played from the same devices, sound different?

 

Yes.

 

Please read Miska comments on the exaSound DACs thread regarding recording embedded jitter!...

 

Roch

 

Can you provide a link to this post?

 

The only thing I could find in that thread was a comment from Miska regarding jitter embedded in the recording itself which I would assume would be same for both files.

[goldsdad]

Come to think of it, how about:

Can the same file, played more than once on the same device, sound different each time?

 

I would have to answer that with a resounding yes. Every time I listen to a piece of music it sounds a bit different, I guess depending on my psychological/physiological/emotional/pharmacological state at the time.

 

That makes the question of bit-identical files sounding different somewhat moot, at least for me, since I can't really listen to them both at the same time.

 

+1

 

(I made the same point some time ago)

[mav52]

Yes, but it is only visible to people who deploy correct punctuation.

 

Here is a thought: If you aren't interested in the topic, don't click on the link to the thread.

 

Last thing I knew it was a free county I live in.

 

So lets look at this different.

 

Can two audio files with the same checksum, played from the same devices, sound different?

What two files, one from complied from an original master and one from someones rip at their home or two from HD tracks ?

[Jud]

Can two audio files with the same checksum, played from the same devices, sound different?

 

Yes.

 

Please read Miska comments on the exaSound DACs thread regarding recording embedded jitter!...

 

Roch

 

Can you provide a link to this post?

 

The only thing I could find in that thread was a comment from Miska regarding jitter embedded in the recording itself which I would assume would be same for both files.

 

From your description that would seem to me to point to the same or a similar mechanism as the one John Swenson pointed to. If timing information can in effect be embedded in a digital file from a recording, then what in principle prevents it from being embedded in a digital file from a rip? Two different rips could have different amounts of jitter as easily as two different recordings.

 

In any case, I don't know that it's useful to be overly concerned about this one way or the other. Take care with your rips or don't, just as you please.

[kumakuma]

From your description that would seem to me to point to the same or a similar mechanism as the one John Swenson pointed to. If timing information can in effect be embedded in a digital file from a recording, then what in principle prevents it from being embedded in a digital file from a rip?

 

My understanding is that in the first case the timing information would be embedded in the actual data (the zeros and ones). I am having a hard time wrapping my mind around the second case where two copies of the same data (same zeros and ones) would have different timing information. Yes, when pulled off the disk perhaps but not while sitting on the disk.

[Jud]

From your description that would seem to me to point to the same or a similar mechanism as the one John Swenson pointed to. If timing information can in effect be embedded in a digital file from a recording, then what in principle prevents it from being embedded in a digital file from a rip?

 

My understanding is that in the first case the timing information would be embedded in the actual data (the zeros and ones). I am having a hard time wrapping my mind around the second case where two copies of the same data (same zeros and ones) would have different timing information. Yes, when pulled off the disk perhaps but not while sitting on the disk.

 

Please look at my post regarding John Swenson's take on this with regard to your assumption of "same zeros and ones." According to John, though the binary values won't change, the electromagnetic values can be very slightly variable.

[kumakuma]

Please look at my post regarding John Swenson's take on this with regard to your assumption of "same zeros and ones." According to John, though the binary values won't change, the electromagnetic values can be very slightly variable.

 

I get that but these electromagnetic values would change each time the file is copied or sent over a data network or refreshed in memory, etc.

[wgscott]

Last thing I knew it was a free county I live in.

 

Sure it is.

 

 

So lets look at this different.

 

 

differently.

 

 

What two files, one from complied from an original master and one from someones rip at their home or two from HD tracks ?

 

Any two files with the same checksum.

[elcorso]

Can you provide a link to this post?

 

The only thing I could find in that thread was a comment from Miska regarding jitter embedded in the recording itself which I would assume would be same for both files.

 

From reading in this CA forum since year 2010 it was stated there is no possibility as such a thing as 'embedded jitter' in a recorded music track, because jitter is produced (depending the kind of jitter) during playback and from a lot of sources (no only the DAC shipset) like leaking ACV from an SPSU, computer noise, etc., etc.

 

If you continue reading Miska in the same thread you read, his explanation regarding the kind of jitter is much better than mine, a plain humble user.

 

Embedded jitter affects checksums? I guess don't.

 

Now we can go to one original music track with no embedded jitter, copied and stored the way you want, zip compressed, zip expanded, transmitted from K-Pax to Aquinostan, and again from Aquinostan to K-Pax. Do the original track versus the transmitted one have the same checksums: Yes. They could have exactly the same SQ if played with exactly the same gear and listened by the same listener, this listener with the same everything: room temperature, blood pressure, mood, etc.? I guess don't.

 

Want a proof? I can't, there is a lot of differences between people, even identical twins. This had being my experience, but a lot of other people experience also, like some kind of Martin Colloms Imagination, you can call it MCI Syndrome that affect some regarded recording engineers to humble listeners like me. There is no cure and no vaccine. But do not worry it is not contagious.

 

Happy listening,

 

Roch

[Snowmonkey]

Last thing I knew it was a free county I live in.

Sure it is.

 

Unless you want to film a factory farm or a slaughterhouse, even if you're standing on public land when you do it.

[kumakuma]

 

Now we can go to one original music track with no embedded jitter, copied and stored the way you want, zip compressed, zip expanded, transmitted from K-Pax to Aquinostan, and again from Aquinostan to K-Pax. Do the original track versus the transmitted one have the same checksums: Yes. They could have exactly the same SQ if played with exactly the same gear and listened by the same listener, this listener with the same everything: room temperature, blood pressure, mood, etc.? I guess don't.

 

I think everyone would agree with you on this but this isn't the issue being discussed here. The issue is whether or not two files that are bit-for-bit identical can *consistently* sound different when played back in the same place, using the same equipment. In other words, is there something in one file that makes it sound different from the other although both files are identical according to computer science.

[Paul R]

Hi Roch- for the moment assuming there is embedded jitter in the file, and there always is, at the end of your multi-lightyear transmission, the reconstructed file will have exactly the same jitter embedded in it as the original file.

 

If there were no transmission errors, then the checksums will match, they will be bit for bit identical, and they should sound the same- if you play them on the same equipment. If they do sound different, it will be From some other cause than the data or files being different.

 

 

 

 

 

From reading in this CA forum since year 2010 it was stated there is no possibility as such a thing as 'embedded jitter' in a recorded music track, because jitter is produced (depending the kind of jitter) during playback and from a lot of sources (no only the DAC shipset) like leaking ACV from an SPSU, computer noise, etc., etc.

 

If you continue reading Miska in the same thread you read, his explanation regarding the kind of jitter is much better than mine, a plain humble user.

 

Embedded jitter affects checksums? I guess don't.

 

Now we can go to one original music track with no embedded jitter, copied and stored the way you want, zip compressed, zip expanded, transmitted from K-Pax to Aquinostan, and again from Aquinostan to K-Pax. Do the original track versus the transmitted one have the same checksums: Yes. They could have exactly the same SQ if played with exactly the same gear and listened by the same listener, this listener with the same everything: room temperature, blood pressure, mood, etc.? I guess don't.

 

Want a proof? I can't, there is a lot of differences between people, even identical twins. This had being my experience, but a lot of other people experience also, like some kind of Martin Colloms Imagination, you can call it MCI Syndrome that affect some regarded recording engineers to humble listeners like me. There is no cure and no vaccine. But do not worry it is not contagious.

 

Happy listening,

 

Roch

[mav52]

Unless you want to film a factory farm or a slaughterhouse, even if you're standing on public land when you do it.

 

Has nothing to do with audio unless you feel audiophiles are animal activist turned terrorist.

[sbgk]

I've tried Sandy's test files. a diff on the 2 files produced no differences so that must be better than comparing checksums and I even compared them side by side. I initially thought there was a difference in sq, but couldn't be sure in random play. If there is a difference then you should be able to copy the contents from 1 file to the other using copy and paste and the differences would be transferred to the target file.

 

If there is a difference then would be good to know the mechanism as it could be used during playback to enhance all tracks.

 

other factors - caching of data, filenames etc

 

also can the human ear actually be sure it is listening to the same track, if you're looking for a difference then there is expectation bias, also the mind concentrates on different parts of the music from one play to the next. By far the largest variable is the human.

 

so am open minded, but not a concern at the moment.

 

Photographers say there are differences in files copied straight from the camera vs from the sd/cf card storage, presumably these differences are visible in picture.

[One and a half]

This topic again.

 

If the files are different, what mechanism is available so they both sound the same? What possible software that can create a PID loop measuring noise and timing variant rejection? That noise is so small and fast, it's barely detectable even with very fast logic analysers. If the file was an Excel file, or a tax return, it's not a problem, if a pixel is gone and reappears, the eye is too slow. Audio timing differences are detected by human hearing from 8 to 20 microseconds and noise is sadly amplified so it is noticeable.

 

Imbedded jitter - don't buy this one. Jitter has a fundamental criteria for existing : time. It is not possible to imbed and capture jitter in a stationary object where the time scale is 0. Voltage disturbances, amplitude irregularities, rounding errors (sloping wavefronts) magnetic media saturation effects, yes, these can reside in the file at the time of storage. Depends of course how bad these artefacts are and whether the playback or storage system ignores these errors.

 

Bit perfect - Other than the developer of the software, can't exist. As soon as a file is pulled off the storage media, it interacts with the electrical system of the renderer or computer and out the USB port. The file is what it is, plus small amounts of ground plane disturbances, RF, which varies from machine to machine. So the music file could sound technically different, as to the degree of awareness of the changes, ranges from 'quite obvious' to 'undetectable' according to this thread, eye of the beholder or ear in this case.

BitPerfect needs another term for when playing back music files of the correct sample rate. Different players have different sound fingerprints due to the different software processing that varies from developer to developer and ultimately interacting with the computer's electrical system.

[Paul R]

Has nothing to do with audio unless you feel audiophiles are animal activist turned terrorist.

 

There's something happening here,

what it is ain't exactly clear.

There's a man with amgun over there,

telling me, I ought to beware...

[Snowmonkey]

Has nothing to do with audio unless you feel audiophiles are animal activist turned terrorist.

Sorry, I got distracted by

Is there a who cares choice.

and

Last thing I knew it was a free county I live in.

[burnspbesq]

It has been proposed that two computer files that encode digital audio (eg, AIFF, Wav, etc) and possess identical checksums, played from the same disk through the same computer, cables, etc, can nonetheless sound different, given their different download history, copying history, or other paths through the space-time continuum.

 

What say you?

 

I don't doubt it for a second, but I think the reasons can most likely be found in that device that resolutely resists repeatable measurement and that so-called objectivists refuse to take seriously for that precise reason, i.e., the brain of the listener.

[new_media]

I've lived in dry counties before, so at least in one respect not "free."

[mav52]

Sorry, I got distracted by

 

and

 

dry county indeed. We spent 2 darn weeks in the mountains trout fishing in Graham County, NC. Had to drive 1hr to get a beer. But no hassles and the rest was a joy including a few 10lb brown trout. Living free and enjoying life in my county in Fla.

[wgscott]

Free as in beer?

 

[ringenesherre]

Photographers say there are differences in files copied straight from the camera vs from the sd/cf card storage, presumably these differences are visible in picture.

 

Unless the pictures are pulled in a different format, size, or reencoded, this is WAY more unlikely than the same situation for audio, as timing is eliminated.