[larry]

I recently went to one audio store to collect my DAC/AMP. Me and the store tender start chit chating about audio stuff. We came to a point talking about computer as source. He told me that he prefer Apple Lossless to WAVE. I ask him why and he told me that Apple Lossless is 90% of a CD quality while WAVE is 80%. I was confuse about this so we decided to test out using his hifi system. I'm not sure what preamp, amp or speaker he is using but through out the test, the following equipment is the same.

1. Preamp w/ amp
2. Speaker
3. DAC
4. USB cable to DAC
5. Same portable DVD drive to rip the same CD

The equipment that is not the same during the test.

1. I am using Asus Eee PC while he use BenQ netbook. (I dunno which model)
2. I am using Vista>Foobar>WASAPI>DAC while he is using XP>iTunes>DAC
3. I rip using WMP to WAVE while he rip using iTunes to Apple Lossless

During the test, Apple Lossless bass is tighter and punch slightly harder, Vocal sound more "live" and the high is crispy. I suspect is the following that cause the different in sound quality.

1. Operating System
2. Ripping software
3. Playback software

Can this justify the title?

 

[sonci]

Yes, but which one was closer to the cd sound?

 

[larry]

The Apple Lossless is closer to CD quality. So if the 3 software change to the same, the out come will be Apple Lossless still leading?

 

[soozieq]

I don't understand. Lossless is lossless.

 

[krmathis]

Audio data wise they should both (Apple Lossless and WAVE (PCM)) be 100% identical to the CD. Some people claim to hear an audible difference though, which may be related to the fact that the Apple Lossless file need to be decoded during playback (consumes cpu cycles, ..).

Foobar (Vista) -> Wasapi -> DAC is (or should) be bit-perfect, while iTunes (XP) -> DAC is not. Take that into consideration as well.

 

[Currawong]

Considering that a an Apple Lossless file is just the same file as the WAV, but compressed, and that de-compressed the same bits will be output, unless something is going on that is changing the actual data, there should be no difference at all. If the rip was done, say, with correct EAC settings, then both are 100% CD quality. what you were told in the audio store is frankly BS.

 

[paaj]

And yet another supposed audio knower that you go to because you think they should know this stuff that gets the basics completely wrong... Why is this still happening?

To make this a valid test, you need to get everything the same, except the ripping-to part. So get him to rip the CD to WAV and FLAC. Of course it would help if he played his files with a bit-perfect player... now I think you're mostly comparing the WASAPI vs Kmixer part.

 

[larry]

Quote:

Originally Posted by krmathis /img/forum/go_quote.gif Audio data wise they should both (Apple Lossless and WAVE (PCM)) be 100% identical to the CD. Some people claim to hear an audible difference though, which may be related to the fact that the Apple Lossless file need to be decoded during playback (consumes cpu cycles, ..). Foobar (Vista) -> Wasapi -> DAC is (or should) be bit-perfect, while iTunes (XP) -> DAC is not. Take that into consideration as well.

Since Apple Lossless file need to be decoded in order to playback so there is one more step in the process while WAVE do not have. Shouldn't WAVE sound closer to CD? I am using WASAPI in Foobar so shouldn't it closer to CD too? Overall the process path from Apple Lossless to DAC is longer then WAVE. I just don't know why.

 

[Little country rat]

Quote:

Originally Posted by larry /img/forum/go_quote.gif 3. I rip using WMP to WAVE while he rip using iTunes to Apple Lossless

I guess this is what's wrong in your setup.

 

[larry]

Quote:

Originally Posted by paaj /img/forum/go_quote.gif And yet another supposed audio knower that you go to because you think they should know this stuff that gets the basics completely wrong... Why is this still happening? To make this a valid test, you need to get everything the same, except the ripping-to part. So get him to rip the CD to WAV and FLAC. Of course it would help if he played his files with a bit-perfect player... now I think you're mostly comparing the WASAPI vs Kmixer part.

I was thinking to justify this title better , I decided to rip my CD to WAV and Apple Lossless using iTunes and playback using iTunes too. The reason I choose to playback using iTunes is because Foobar itself do not support Apple Lossless. So by doing this I guess I can get a very fair test.

 

[larry]

Quote:

Originally Posted by Little country rat /img/forum/go_quote.gif I guess this is what's wrong in your setup.

I have high suspect in this too. It is because that time at the shop there I do not have iTunes or EAC on my netbook.

 

[paaj]

Quote:

Originally Posted by larry /img/forum/go_quote.gif I was thinking to justify this title better , I decided to rip my CD to WAV and Apple Lossless using iTunes and playback using iTunes too. The reason I choose to playback using iTunes is because Foobar itself do not support Apple Lossless. So by doing this I guess I can get a very fair test.

There is a plug-in for foobar that plays ALAC. Of course, you could use FLAC just as well. Same idea. Use EAC to rip, Foobar/wasapi to playback and then you can test again

The first part of my post was not aimed at you, but at the salesman. Claiming ALAC is better than WAV but worse than CD, when in fact they contain the same data just gets my hairs up.

 

[Daroid]

PCM Wave files IS a perfect representation of the bit-for-bit content of the CD. It uses no statistics to encode, and thus the file size is stupidly large.
Apple lossless uses LPC (linear predictive coding) to estimate a stationary part of the music from the knowledge it has regarding the sample values of the available signals (it's autocorrelation). It would do so for each, let's say 15 ms or so. It depends a lot on the signal. The output of LPC is a number of coefficients which represents the estimated samples (if you filter these by white noise). These are still only an estimate, since it is predictive. You also compare the original signal with the predicted, and store the reisudal (error) signal - which can likely be done using few bits, since the dynamic range would be relatively low.

When this is done you have all you need to represent the wave file losslessly. How Apple did the implementation, or if there are more tricks, i have no idea.
The Wave file and Apple lossless file thus should be 100% identical when decoded and played.
You can re-encode the Apple lossless file as PCM wave and subtract the two wave files you now have. I know matlab can do this for you easily, but there got to be other (and free) tools. If the resulting output is silent, all you heard was placebo

 

[krmathis]

Quote:

Originally Posted by larry /img/forum/go_quote.gif Since Apple Lossless file need to be decoded in order to playback so there is one more step in the process while WAVE do not have. Shouldn't WAVE sound closer to CD?

No, it should not. Cause when decoded the audio data (PCM) sent from the computer to the DAC should be 100% identical. I use "should", as some as mentioned above claim to hear a difference and hence their audio data can not be 100% identical.

 

[Bredin]

Did you know what fileformat you where listening too? It could be placebo.