Playing AIFF files

[mistergsf]

I have an Apple TV and I've started to copy the original AIFF files from my CDs to iTunes rather than importing as Apple Lossless. I was wondering what differences there are in playing an actual CD vs. playing the AIFF file (from iTunes) on my Apple TV. In other words, what sounds better, playing the CD or playing the AIFF from my computer (via Apple TV). I feel I have "audiophile" ears and I can't tell any difference. But I can tell the very subtle differences between the Apple Lossless file and the AIFF file.

 

[dkane360]

I believe both are lossless, so if you dont hear a difference, thats a good thing

as for the subtle differences between apple lossless and aiff, I have no idea what would cause that.

 

[mistergsf]

I believe both are lossless, so if you dont hear a difference, thats a good thing

as for the subtle differences between apple lossless and aiff, I have no idea what would cause that.

My curiousity was more about playing a CD (aiff) on a very good CD player vs the same aiffs being played from a compiter hard drive. Are they really equal technically/sonically?

As for Apple Lossless sounding subtly different from an aiff, I wasn't implying that I was surprised by that. It just took a pair of $2600 speakers and a $3000 amp to help me notice it. Having really good equipment is making me appreciate good sound again even though I still love the convenience of ripping my CDs into smaller AAC files and cramming it all on my iPod. There is still some compression in Apple Lossless but it does come pretty close to sounding like the original.

 

[MDS]

My curiousity was more about playing a CD (aiff) on a very good CD player vs the same aiffs being played from a compiter hard drive. Are they really equal technically/sonically?

An audio CD does not contain AIFF files or any other kind of file. It contains 16 bit linear PCM samples and the program you used to 'rip' the CD created an AIFF file.

An AIFF file is the equivalent of a WAV file on Windows although the header format is slightly different; in other words it's nothing more than a header that describes things like sampling frequency, bit rate, how many channels, etc followed by the actual samples that were ripped from the CD. It will sound identical to the CD because it *is* identical to the CD.

As for Apple Lossless sounding subtly different from an aiff, I wasn't implying that I was surprised by that. It just took a pair of $2600 speakers and a $3000 amp to help me notice it. Having really good equipment is making me appreciate good sound again even though I still love the convenience of ripping my CDs into smaller AAC files and cramming it all on my iPod. There is still some compression in Apple Lossless but it does come pretty close to sounding like the original.

A lossless codec compresses the size of the *file* (analogous to zipping a bunch of files although the algorithm to do so is quite different). A lossless codec does not discard anything from the original file so unless the codec is broken, it cannot sound any different than an uncompressed WAV/AIFF or the CD itself. It doesn't sound 'pretty close to the original' - it is the original.

It is possible that when playing it back on a computer there could be very tiny differences in timing, relative to playing it on a dedicated CD player, due to latency of the hard disk and how busy the machine is but such differences are almost imperceptible.

 

[mistergsf]

An audio CD does not contain AIFF files or any other kind of file. It contains 16 bit linear PCM samples and the program you used to 'rip' the CD created an AIFF file..

When I stick an audio CD into my Mac/PC and it mounts on my desktop, and then I double click to open it to see its contents, there is no "ripping" involved. The contents of the audio CD are aiffs. I'm not sure what you are saying that "an audio CD does not contain AIFF files or any kind of file."

 

[MDS]

When I stick an audio CD into my Mac/PC and it mounts on my desktop, and then I double click to open it to see its contents, there is no "ripping" involved. The contents of the audio CD are aiffs. I'm not sure what you are saying that "an audio CD does not contain AIFF files or any kind of file."

An audio CD (ie 'Redbook'), whether it is a commercially pressed disc you bought at a music store or one you burn yourself onto a CD-R, contains 16 bit PCM samples. There is no table of contents and no files of any kind.

A data CD has files. A disc that contains audio files is not an audio CD - it is a data CD that contains audio files. If it's an audio CD, you have to use Digital Audio Extraction (aka 'rip') to get them from the CD. Files on a data CD can be copied the same as any other file on a hard disk, floppy disc, USB key, etc.

On Windows, if you view the contents of an audio CD you see 'Track01.cda, Track02'.cda, etc (.cda == cd audio) but they do not contain any audio data at all - it's just a pointer to the actual data on the real CD so that when you double click it, Windows can launch the CD player and begin playing that track as long as the CD is in the player. I suspect that the Mac shows the same thing but names its pointer with a '.aiff' extension.

Here's an easy test: copy that .aiff to the hard disk, remove the CD from the CD drive, and then try to play that .aiff. If it is an audio CD, it will either do nothing or pop up an error dialog.

 

[mistergsf]

Here's an easy test: copy that .aiff to the hard disk, remove the CD from the CD drive, and then try to play that .aiff. If it is an audio CD, it will either do nothing or pop up an error dialog.

Okay, (on my Mac) popped in Diana Krall, "Love Scenes"; double-click to open and see contents; copying "01 Audio Track.aiff" by dragging to my desktop; ejecting CD; double-click on "01 Audio Track.aiff"; iTunes launches to play AIFF; I am now listening to "All or Nothing at All".

BTW, I know all about the Red Book Standard/44.1 khz, 16-bit PCM encoding. A few weeks ago I pulled an old back issue of The Absolute Sound magazine from Sept. 2007 from a online document exchange site. It contained a very long article celebrating the 25th anniversary of the compact disc; very fascinating! So I feel I'm up-to-date again with my knowledge of the CD format. Anyway, it was because of this article that I posted my question. You see, I feel like I'm a "born again audiophile". Back in the late 70's to 80's when I called myself an audiophile, we were living in an analog world. Now that I'm getting back into high-end audio and video, we are in a digital world that is much more complicated than the analog days. I appreciate you taking the time to indulge in answering my questions. I really am very curious about all of this and I'm reading so much stuff on the internet.

 

[MDS]

Note this key phrase: copying "01 Audio Track.aiff"

It performed DAE (ripping) when you dragged it and now you do have an actual .aiff file.

I meant copy the '01 Audio Track.aiff' using the command prompt so you don't have the magic of the GUI automatically ripping for you and you'll see it's nothing more than a reference to the audio track and not the track itself.

 

[mistergsf]

Note this key phrase: copying "01 Audio Track.aiff"

It performed DAE (ripping) when you dragged it and now you do have an actual .aiff file.

Oh, OK. I got it. So really, the digital audio extraction happened in the background and "ripping" didn't have to involve iTunes; the OS did it on it's own.

So, going back to my original post, playing a CD in a very good player vs. the AIFF from a computer hard drive is exactly the same thing, barring any errors or discrepancies from the player or the computer; and if there were errors, it should not be very noticeable. Would you agree with this final conclusion?

Thanks!

 

[MDS]

So, going back to my original post, playing a CD in a very good player vs. the AIFF from a computer hard drive is exactly the same thing, barring any errors or discrepancies from the player or the computer; and if there were errors, it should not be very noticeable. Would you agree with this final conclusion?

Thanks!

Yes. Bits are bits and if two copies are identical they will sound identical.