iTunes does not rip accurate audio data
Jan 31, 2008 at 1:51 AM Post #121 of 199

bigshot

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What exactly does all those swell extra kbps buy you?

See ya
Steve
 
Jan 31, 2008 at 2:13 AM Post #123 of 199

IPodPJ

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Well, I just noticed that I dumped the folder with the ALAC file in it last night that I was using to compare. And I can't re-rip it again since I gave my neighbor back his CD and he's not home now.

So I am going to use a different CD and do it again right now. It just won't be Vivaldi. But I expect the same results.
 
Jan 31, 2008 at 2:45 AM Post #124 of 199

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Ok, I just ripped the song "So Called Friend" from Porcupine Tree's CD single: Lazarus.

I first ripped a WAV file with EAC.
Then I ripped a WAV file with iTunes.
Both are exactly 4:49 and 48.64MB.
Again, we have extreme differences as you can see here:


Comparing:
"F:\EAC extracted music\Porcupine Tree\Lazarus (CD Single)\itunes rip\02 So Called Friend.wav"
"F:\EAC extracted music\Porcupine Tree\Lazarus (CD Single)\Porcupine Tree - Lazarus - 02 - So Called Friend.wav"
differences found: 25221836 sample(s), starting at 0.0056009 second(s), peak: 1.9998779 at 3.7118141 second(s), 1ch


Ripped on iTunes 7.5, Windows Vista 32-bit

EAC rip of the song
Free file hosting by Savefile.com

iTunes rip of the song
Free file hosting by Savefile.com


Disclaimer: These files are for comparative purposes only. Once you are done comparing them, please delete them as it would be against copyright law for you to possess them.
 
Jan 31, 2008 at 3:19 AM Post #126 of 199

dkjohnso

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Quote:

Originally Posted by xenithon /img/forum/go_quote.gif
IPodPJ - do you have an offset configured in EAC perhaps?


I was just about to mention that. I imported the tracks into Audacity, and they are just slightly out of sync. I can upload a screenshot if people want to see it.
 
Jan 31, 2008 at 3:19 AM Post #127 of 199

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Quote:

Originally Posted by xenithon /img/forum/go_quote.gif
IPodPJ - do you have an offset configured in EAC perhaps?


How would I find out?

I know when I installed it it asked me about my preferences, and I chose the accurate rip setting.

I'm curious to know how many people are using XP and how many are using Vista. It seems like XP does not have this issue based on some previous posts.
 
Jan 31, 2008 at 3:39 AM Post #129 of 199

dkjohnso

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Quote:

Originally Posted by hciman77 /img/forum/go_quote.gif
I just compared those two files in Audacity - they are not perfectly aligned - sadly I cannot post a comparison gif but in Audacity they are slightly misaligned - and this is right at the beginning of the file, thus the two files will show up as almost completely different. The WAV files however do look as near identical as possible with the exceptiion of the alignment problem.....


Here's what it looks like:
http://www.princeton.edu/~dkjohnso/audacity.bmp

They are about .000139 seconds out of sync, which is 6 samples. You can change offset in EAC by going to the drive options, but I don't think you can change iTunes offset. But, I don't think this would make an audible difference anyway, would it? The waveforms do indeed look identical except for the offset.
 
Jan 31, 2008 at 3:40 AM Post #130 of 199

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As nearly identical as they may look, I assure you they sound very different. But thank you two for confirming to everyone that they do have different waveforms. I already knew I wasn't crazy, but I guess some people (wink wink Pete) think you are just because they may not be able to hear the differences.
tongue.gif
 
Jan 31, 2008 at 3:43 AM Post #132 of 199

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Quote:

Originally Posted by dkjohnso /img/forum/go_quote.gif
Here's what it looks like:
http://www.princeton.edu/~dkjohnso/audacity.bmp

They are about .000139 seconds out of sync, which is 6 samples. You can change offset in EAC by going to the drive options, but I don't think you can change iTunes offset. But, I don't think this would make an audible difference anyway, would it? The waveforms do indeed look identical except for the offset.



When you open them up in Audacity, why are the files showing up as 32-bit floating point? Did you convert them from 16-bit?
 
Jan 31, 2008 at 3:45 AM Post #133 of 199

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Quote:

Originally Posted by dkjohnso /img/forum/go_quote.gif
BTW, killer band. I've never heard their stuff before. I will have to pick up this album.


You can't pick up that album. It was a limited CD single, and my copy was promotional. If you can find a copy I'll be shocked.

But yeah, they are one of the best bands around today. I've been a fan since the early 90s, have their entire catalogue as well as limiteds and autographed stuff. I prefer their earlier stuff as it wasn't quite as heavy as the newer stuff. Pick up a copy of their live DVD. It will blow you away.

If you want some suggestions on material, I'll be happy to assist. But check out the DVD first. It's a good all-rounder.
 
Jan 31, 2008 at 3:48 AM Post #134 of 199

dkjohnso

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Quote:

Originally Posted by IPodPJ /img/forum/go_quote.gif
You can't pick up that album. It was a limited CD single, and my copy was promotional. If you can find a copy I'll be shocked.

But yeah, they are one of the best bands around today. I've been a fan since the early 90s, have their entire catalogue as well as limiteds and autographed stuff. I prefer their earlier stuff as it wasn't quite as heavy as the newer stuff. Pick up a copy of their live DVD. It will blow you away.



Dang, too bad. I guess I will check out their other stuff. Thanks.

And the "default sample format" in Audacity was set to 32-bit. Not sure what it does: I set it to 16-bits and re-imported. Same results.
 

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