Will there be a degradation in quality?

[salannelson]

I bought a few albums from the iTunes store a while back encoded in 256kbps AAC. I encoded them into Apple Lossless right when I bought them, wasting a LOT of space on my HD and doing nothing to improve sound quality (I used to think that encoding songs into Apple Lossless would actually improve sound quality).

SO.. my question is would the quality be affected if I re-encoded the songs into 320kbps AAC or MP3?

 

[logwed]

Just use the original 256 files. You should still have copies of them. Anyway, the quality should not be affected by changing formats.

 

[salannelson]

Quote:

Originally Posted by logwed /img/forum/go_quote.gif Just use the original 256 files. You should still have copies of them. Anyway, the quality should not be affected by changing formats.

I don't have the original files. I would use them if I did.

 

[logwed]

Also, why are you switching to 320? The files are maxed at the level you are downloading them. You cannot improve SQ by switching them to a higher bitrate.

 

[leeperry]

reencoding is always lossy, so go w/ the highest rate available....can't you get them again from itunes anyway ?! you paid for a licence, not for the file itself.

 

[logwed]

Quote:

Originally Posted by leeperry /img/forum/go_quote.gif reencoding is always lossy, so go w/ the highest rate available....can't you get them again from itunes anyway ?! you paid for a licence, not for the file itself.

Is that how iTunes does it?

To the OP, to clarify, upconverting your files will not ever improve the quality. The option exists to down/side convert in order to limit file space, or improve/change compatibility.

 

[salannelson]

Quote:

Originally Posted by logwed /img/forum/go_quote.gif Also, why are you switching to 320? The files are maxed at the level you are downloading them. You cannot improve SQ by switching them to a higher bitrate.

I know. I just want to avoid any degradation if possible.

 

[salannelson]

Quote:

Originally Posted by leeperry /img/forum/go_quote.gif reencoding is always lossy, so go w/ the highest rate available....can't you get them again from itunes anyway ?! you paid for a licence, not for the file itself.

Nope. Just checked the terms of use.

 

[Bonthouse]

LOL, you encoded a lossy into a lossless? That's not how it works!

 

[salannelson]

Quote:

Originally Posted by Bonthouse /img/forum/go_quote.gif LOL, you encoded a lossy into a lossless? That's not how it works!

I KNOW!!!!!!!!!!! THIS WAS A WHILE AGO I DIDN'T KNOW!!!! CAN YOU JUST ANSWER THE QUESTION?????

 

[tot]

Quote:

Originally Posted by salannelson /img/forum/go_quote.gif SO.. my question is would the quality be affected if I re-encoded the songs into 320kbps AAC or MP3?

It would. Since the source of the lossless file was a lossy one, it already contains compression artefacts which the new encoding knows nothing about, and the encoder tries faithfully to reproduce them too, which takes even more "space" from the actual content. Not to mention that new artefacts will be introduced on top of old ones.

 

[salannelson]

Quote:

Originally Posted by tot /img/forum/go_quote.gif It would. Since the source of the lossless file was a lossy one, it already contains compression artefacts which the new encoding knows nothing about, and the encoder tries faithfully to reproduce them too, which takes even more "space" from the actual content. Not to mention that new artefacts will be introduced on top of old ones.

Thank you. Finally someone actually answered the question. That makes a lot of sense. I'll try to find the originals and use those or just leave them alone.

 

[Ham Sandwich]

Quote:

Originally Posted by salannelson /img/forum/go_quote.gif Thank you. Finally someone actually answered the question. That makes a lot of sense. I'll try to find the originals and use those or just leave them alone.

Tot's explanation is correct.

If you can't find the original AAC files then make a note in the tags of the ALAC file that the source was a lossy AAC file so you'll be able to keep track.

The good news is that I believe converting the iTunes AAC file to ALAC may have broken the DRM so the files are actually more useful now (can be played on more players). And you can always covert the ALAC to another lossless format like FLAC or WMA Lossless for support on players that don't do ALAC.

So no harm done other than wasted space and you have to remember that converting those particular ALAC files to lossy will compound lossy compression artifacts.

 

[krmathis]

Yes!
You will loose additional audio data when transcoding those Apple Lossless files to AAC, since they have already been lossy encoded. If the loss is audible it all up to you to decide.

Quote:

Originally Posted by Ham Sandwich /img/forum/go_quote.gif The good news is that I believe converting the iTunes AAC file to ALAC may have broken the DRM so the files are actually more useful now (can be played on more players).

His 256kbps AAC files have never been DRM protected in the first place. Only 128kbps AAC files sold through iTunes Store were DRM protected.

 

[aristos_achaion]

Quote:

Originally Posted by salannelson /img/forum/go_quote.gif I bought a few albums from the iTunes store a while back encoded in 256kbps AAC. I encoded them into Apple Lossless right when I bought them, wasting a LOT of space on my HD and doing nothing to improve sound quality (I used to think that encoding songs into Apple Lossless would actually improve sound quality). SO.. my question is would the quality be affected if I re-encoded the songs into 320kbps AAC or MP3?

Yes, it would. As you found out, there's no way to restore the data lost in a lossy encoding; however, re-encoding those lossless files to lossy will remove even more data, degrading sound quality further. Whether you'll notice the difference is another matter; try it and see what you think (can't hurt). Just keep the originals around.