Calling all experts on digital music data

What is identical? The audio bits or the complete file? HDCD? Pre-emphasis?

Also check how the files are stored on the secondary disk drive so both are fully sequential (including bad data on the disc). Make sure you dont have any compression on the secondary storage. Prefer HDD as SSD:s have more stuff going on internally and are more sensitive to rewrites.

Are you storing as 44/16?

You can also try a NOS-DAC to avoid the interpolation and increased jitter sensitivity in oversampling.

Also clean the CD before ripping.

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Remember there are no digital devices. It is all analog which is interpreted as digital which is then interpreted as analog.

Re all your questions, please see the report I copied in post 6.

And my “exactly” was to “there’s something making a difference”. The question is, given the reported test, what? And what further tests can be done to find out?

My money is on this explanation.

I’d want to see the experiment done blindly, with random playback of one or the other rip. Then see if listeners can with statistical significance identify a vs. b.

Absent this, it’s just subjective “they sound different” reports, which can neither be “proven” nor “disproven.” And as such isn’t a very interesting experiment. To me.

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Because there are those you play music to listen to their system, and there are those who play their system to listen to music. The former obsess over these things and die early from too much stress. The latter enjoy long lives listening to music. :wink:

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And so would mine be, unless the listening was done blind, and repeatable. However, what piqued my interest was the statement that when analysed with Audacity there was a visible difference.

The first thing I would do is some verification, doing the same with more with more tracks, if the original person has the time and is willing, better still with more people having access to the Melco ripper joining in.

Meanwhile my question was, is it there anything that can be different but appearing the same when the file is analysed with cmd? SiS suggested file headers, but wouldn’t that show with cmd?

@Peter1480, Could the files be shared by dropbox? May need to be copyright-free music - if there is any such thing on CD.

Play the same CD twice, does it sound exactly the same both times? How do we decide if it does?

What if you burn a CD from a rip with XLD or whatever and then rip that. CD with a Melco. Does it now sound better?

If a Melco rip looks quieter in Audacity than dBPowerAmp rip then how can the two rips be bit identical?

I’ve gone passed the point of worry. I have accurately ripped 1000s of CDs. Not going to do it again. My rips sound great to me and I’d rather be happy than right.

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Well, the devices are not in play here. The files containing the data are identical. No wires, no analogue components. No timing components. Only data. I can certainly appreciate physical components having a say, but the pure digital representation is simply not susceptible to variation; that would be an error.

I am a software engineer, true. I am also a musician.

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Given that:
cmp on Linux should compare all of the file data, including the headers (assuming a straight cmp was done and no bytes skipped).
Audacity should do nothing more than read the file data (and not take information from any other source).

The problems that I see are:
What is meant by ‘quieter’ in the Audacity analysis (is this objective or subjective?).
listening tests are subjective (and definitely not objective).
Unless the subjective tests were done double blind, they could be dominated by psychological bias.

That echoes what I think

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I assumed that the OP meant that he had used audacity to compte a waveform view (or a spectral view) of the two files and found the one was “quiter” than the other. This is of course impossible if the files are identical which suggests that he perhaps meant something else. Or that the files are actually not identical.

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There is no dark side of the moon. Matter of fact it’s all dark.

As the OP that in part caused the thread, I’m still enjoying the music, be it new Melco rips or those done 20 years ago on PCs but I would still love what is going on with the Melco D100 rips. I wonder if the Innuos Statment users feel the same about their rips done in the player?

Well yes:

  • Any real-world physically existing device is in the end some analogue device, which interacts with it’s environment via physical (or maybe chemical) interaction.
  • If the abstraction from the analogue world on modern computer systems and data networks would not be working “pretty well” (=very low bit error rates, except when going to radio transmitted data, where you add a lot more correction in the physical and binary domain to achieve similar reliance like on copper of optical cables) then only few of modern digital applications would be working: banking, flight control, distributed computing, “cloud stuff” (getting mails, documents, whatnot which arrives “the same” as it was sent), … - and this works most of the time, as e.g. checksums, digital signatures, etc. pp, prove. Or just the fact, that the same password gets you into the system “all of the time” (unless you mistype, of course :wink: ).

So:

  • “Within the digital computer processing handled by typical IT systems”: There’s NO information in “digital data” which might hide “between the bits or in the form of bits, or whatnot”. Otherwise our “modern IT world” would not work. By the way: one of the “powers” of digital transmission is, that you constantly generate analogue representation of your data and “re-parse” it to digital values before passing the data on. This is the only way to prevent “error propagation”, which you can never prevent in the analogue world - but regenerating a new signal on each hop (dozens or more) has given us pretty good audio and video quality in “live/real-time” streams across the world. And tons of millions of those in parallel.

But also:

  • Whatever we perceive as humans, is for sure not digital, but converted by some device back from the “virtual digital domain” to our analogue world.
  • This implies, that of course, there can be various physical influences on any data conversion from digital to analogue - once you start producing an analogue signal. (So for audio: from “within DAC” onwards in the chain.)
  • Any lossless 1:1 replication of bits before the DAC (given “absence of bit errors”) just by definition cannot have an impact on the result of “after DAC”; except for any analogue side effects, which reach the DAC or other devices behind it during the conversion and playback. (Just to be clear: this influence would be transmitted analogue to the point of effect; this could be on the same cable which transmits the signal with the “digital data” - but it would not be “hidden in the digital data”.)

Any objections? :wink:

If yes, further discussion from my will be postponed, until the time we’re in the same room at the same time using whatever digital and analogue sources and devices in question and can at least try to come to a common view. (We cannot compare or finally judge the analoge results on any system in a digital forum. :wink: )

The problem with this thread is the source of information. Who heard a difference? What are their qualifications? Who did this Audacity test? Are you sure they didn’t make an error? Was this even a valid test?

Two identical files will sound the same. Period. You’re going to trust an unreliable brain that hears a difference? Not a good choice.

It also doesn’t matter about the switch as one person was postulating. The bits are going to come through just as they were sent. The TCP/IP protocol guarantees this. Period.

As an electrical engineer and datacom software developer, I know how this stuff works. It is all nonsense to think they sound different when they’re the same. Just sit back and enjoy the music without all this paranoia and non technical beliefs. :slightly_smiling_face:

Is it possible that noise is embedded in the bits, but not being detectable ?

No.

There could (and will) be noise in any analogue representation of the bits (in a transistor, in a signal on a copper line, …) - but this noise will be “gone”, once the signal is digitized by the receiver again, before being transmitted again to the next destination… essentially there’s many copies of the same (binary) data, which in the analogue world look different, but for the computers (due to “safety margins” in transforming back to digital) are not. Otherwise there would be no 1:1 replication of digital data.

The only “noise” of digital data which can affect the DAC is the last analogue image of digital representation of the data in the DAC itself, before it transforms the data one last time to analogue.

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Not of any Innuous users say they sound better or different.

Everyone seems to be missing the obvious here -

people assume that time is a strict progression of cause to affect, but actually, from a non-linier, non subjective point of view it is more like a big ball of wibbily wobbly timey wimey…stuff.

.sjb

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Imagine a chain of people who can just say “yes” or “no” to each other, one after the other. (And they all know, that this limitation affects everybody else as well. So whatever they hear, must have been a “yes” or a “no”.)

Given the first person says “yes”, there is a very high likelyhood, all will hear, understand, and say again “yes” - so the last person will hear “yes”. If somebody relays a “no” you have a bit error. :wink:

Of course each person will pronounce “yes” differently. But if you are the person who hears the last “yes” pronounced by the last person, you will only hear the voice and intonation of that last person.
You won’t mind or be able to tell, if the initial “yes” from the first person had an accent, was clear to understand, … you only know, it was clear enough, so that the 2nd person in the line thought it more likely to be a “yes” than a “no”.

(Just making up bad analogies on the fly… :innocent: )

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