What does Match do to Apple Lossless and AIFF?

Ars Technca reported that if your lossless tracks match, the iCloud version will be the 256kb version that's available within the Store. The ALAC tracks will remain in that format on your primary library.

For those which don't match, they also reported that the ALAC format is retained. Considering how long it's taking to upload my ALAC tracks on a 5mb/s upload connection, I sure hope it is retained!

I can confirm that WAV files are retained as WAV within iCloud if there is no match. However, I have more testing to do on the ALAC side. So far, my ALAC tracks are appearing at 256KB within iCloud, even though these tracks are not for sale, at least currently and within the US iTunes store.

At least in my limited test, ALAC files are converted to AAC w/variable bit rate.

An Apple Lossless encoded track, bit rate of 702 kbps, 18.1 MB in size, went up to iCloud and came down as an AAC file with a bit rate of 256 kbps (VBR) and a size of 7.9 MB.

Matched stuff just uses the matched versions, so 256.

According to Apple's documetnation, unmatched stuff above 320 is converted down to 256 AAC when it's uploaded.

Thanks for clarifying Mike. I went back to my WAV file test and although it still is a WAV file, the bit rate has been dropped to 256.

So Ken, back to your original question:

I have all my music imported as Apple Lossless. Will I lose quality if I use Match?

The answer is yes.

Actually that is an incomplete answer and could give the wrong impression.

For ALAC and other high bit rate file Itunes TEMPORARILY creates a 256 file to upload to Icloud. That file is then discarded.

Your ALAC etc. files will not be changed on your hard drive.

This is the process Apple outlines on their website.

tomjtx wrote:

Your ALAC etc. files will not be changed on your hard drive.

This is the process Apple outlines on their website.

Yes, we know this. But the question is about what happens to that non-matched lossless file (ALAC, WAV, AIFF, etc.) when it is downloaded to an iDevice. Is it still the lossless file, at the same bit rate? Or, as Douglas has shown, is that file down sampled to 256 Kbps.

From the results Douglas is getting is appears that the downloaded lossless file is being downsampled and is no longer lossless.

Yes, that it what I said :-)

Itunes temporarily converts the file to 256 in order to upload it to Icloud but leaves the ALAC file on your computer HD.

When you play back from your computer where the original file is stored you play the ALAC file.

If you download the file to another Idevice from Icloud you will of course have a 256 file, which should be quite adequate for on the go listening.

EG, When I stream to my hi end home stereo useing squeezebox server through Itunes on my Imac it streams full ALAC files, not 256 files. And I am talking about files which were uploaded to Icloud, NOT matched.

I was very careful to verify this before uploading more than a few files.

I don't want 256 streaming to a 70,000.00 system :-)

Can you provide a source of this info? What documentation?

Search the threads on this site. I clicked a link to apple support with all the info

andrewhake wrote:

Can you provide a source of this info? What documentation?

http://support.apple.com/kb/HT4914

Songs encoded in ALAC, WAV, or AIFF will be transcoded to a separate temporary AAC 256 kbps file locally, prior to uploading to iCloud. The original files will remain untouched.

Awesome has all the info I was looking for.

Definitely a shame you can't actually stream to iOS devices. Will be headed to http://www.apple.com/feedback tonight I guess...