iTunes File "Up"-Conversion

[Quickley17]

I've been looking around for a while and haven't found an answer I feel comfortable with regarding this...

When you download a song from iTunes, you get their compressed version of the song, I think at 128 kbps and it ranges but your typical 3-4 minute song is 3-5 MB. iTunes has the option to convert the file to WAV or Apple Lossless. How does this work? Is the file actually a CD quality file? Does it use a "reverse" algorithm to guess what was once present?

 

[mgsylvestre]

I doubt that this would be useful

I am much more knowlegeable in photography, but I believe the following to be correct.

A still picture or audio file contains information. I you compress the information using a lossy scheme, you loose part of the information. The information is thereafter gone and resaving your file in a lossless format does not have the effect of retrieving the information which was lost in the first place.

Of course, recompressing your file again using a lossy scheme is a bad idea, as you will yet loose even more information.

That is why compressing jpegs again and again is a bad idea, and the same is probably true in the audio world.

Hope this helps.

 

[itschris]

Itunes is certainly not CD quality and conerting to WAV does not get you back there. As MG stated above, if you compress using a lossy scheme, you lose the data in the process.

This does raise another question about the state of audio. It's difficult to deny the popularity of Itunes, yet so many users seem to take no issue with paying more per song than the average CD for far less quality of a CD. Now true, there is the advantage of picking and choosing songs, convenience, etc, but I'm surprised this is largely a non-existent beef that people have.

I would never suggest that I have "golden ears" but I can tell there's a signficant difference between Itune copies and well done CD's. The detail or nuance seems to be missing much like the difference between watching Hi-Def vs standard TV. The movie or show is the same, but something's just missing... the detail. I seem to really notice the difference in the treble tones such as hi-hat work and other cymbal strikes. it just seemd to muddy together on the lossy compressed formats.

 

[Polygon]

As mgsylvestre and itschris has said. iTunes uses a lossy format and that mean that original data from the source file has been lost. There is nothing you can convert it to, to make it sound better. You're kind of stuck with what you have.

Garbage in, garbage out applies here.

 

[itschris]

Do any of the other download services have lossless files? Someone told me Zune does, but I haven't had the chance to dig into it.

Also, just for the hell of it, I did some a/b comparisons last night between Foo Fighters Everlong CD track vs Itunes. There's a lot of high hat on that track and you can certainly hear the difference in clarity (I don't what else to call it). The Itunes version just doesn't have the crispness of the cymbal strike that you get with the CD. Even my daughter thought it sounded different and she didn't even know what I was doing. I just asked her which one sounded better.

 

[jeanseb]

Four house music fans, beatport.com offers lossless audio files (.wav).

 

[Quickley17]

Thanks for the answers guys. I was pretty sure that iTunes wasn't getting the true information from anywhere, but it is kind of funny that it makes the file ten times the size that it was. I guess it just fills it with fluff?

+1 on itschris' question, are there other places online to buy these songs? Do people have good luck with getting the quality they expect from any that are around?

 

[Adam]

This does raise another question about the state of audio. It's difficult to deny the popularity of Itunes, yet so many users seem to take no issue with paying more per song than the average CD for far less quality of a CD. Now true, there is the advantage of picking and choosing songs, convenience, etc, but I'm surprised this is largely a non-existent beef that people have.

Now that the original question has been answered, I'll comment on this. I'm pretty sure that it's been discussed a few times here, as it is a very reasonable observation.

There's a few reasons for the compression to not be a huge issue, IMO. If someone is using a portable player (like an iPod), they probably can't tell much if any difference. Even on the average computer audio system or car system, it's probably tough. So, some people may never notice. Also, some younger people these days may have never heard (or have rarely heard) uncompressed audio - well, of any music that they want to listen to (they might not care for their parents CD collection). That, and the mixing that is done on a lot of modern CDs probably makes the compressed music not sound much worse.

The level of compression of the original iTunes songs kept me from buying very many, probably under ten. I didn't like it. I'm guessing that we aren't alone in that, because Apple reduced the level of compression on the iTunes store (I think it used to be iTunes Plus, but I don't know if it still is). Enough people must have had a beef with it, or Apple probably never would have made the change.

 

[GTOhaas07]

I like how easy it is to use iTunes and the ability to load everything on my iPhone. I usually buy a CD, if I really like it, and import it to iTunes using either Apple Lossless or AIFF. Apple Lossless for me is usually around 1100 kbps vs. 128 for iTunes download. AIFF is even better at around 1400 kbps.