Thread: Extract identical wavs

Recently I tried to rip the same cd's tracks on two different computers with different model drives to check to see if I could get the same wave files.

When I use the compare wavs command found in EAC, I found that one drive consistently included 18 repeated samples. That is, when I compared each of the four files, I always got the same results, 18 repeated samples.

When I compared the tracks in foobar2000's binary comparitor, I get the following

QUOTE
1.) differences found: 21027355 sample(s), starting at 0.21161 second(s), peak: 1.605621 at 163.7676 second(s), 1ch
2.) differences found: 23171401 sample(s), starting at 0.2195465 second(s), peak: 1.587402 at 93.74224 second(s), 2ch
3.) differences found: 23476705 sample(s), starting at 0.2186395 second(s), peak: 1.057007 at 141.2167 second(s), 1ch
4.) differences found: 21403817 sample(s), starting at 0. second(s), peak: 1.482056 at 194.0902 second(s), 2ch

I don't know how exactly to read these results, except to say that the differences in the samples is pretty consistent. I think if I worked a little harder at adjusting the offset on each of the drives I could get the files to be closer to each other.

Is this correct? Is it possible to extract two exactly the same wave files on two different computers with two different model drives? Should I continue to adjust the offset? Any advice or help would be appreciated.

If you want to have identical files extracted with different drives then you must use read offset correction on your drives. -Martin.

I have set the read offset. I thought I set it correctly. After I set the offset, I again ripped and reripped a few tracks compared them with no missing samples. I guess I was just asking if I should keep trying to find better offset values, maybe the average of a few tests with read offset turned off.

Would this get me better results between the two computers? Or is it hopeless, should I just accept it thinking 18 repeated samples isn't that much?

Install AccurateRip and use that to find your exact drive offsets(according to Andres reference). Also if your drives dosent overread into the pregap/lead-out then the first or last track of a disc wil not be identical with different drives. -Martin.

Originally Posted by Martin

Also if your drives dosent overread into the pregap/lead-out then the first or last track of a disc wil not be identical with different drives. -Martin.

They may be identical if "Fill up missing offset samples" is set in "EAC options" > "Extraction"
But as Martin says, test your settings with AccurateRip, it's great!

Yes, atramhasis is of course right...

If there is enough null samples at the beginning of first track/end of last track(according to the drives positive or negative offset value), and "Fill up missing offset samples with silence" is enabled, then being able to overread or not dosen't matter...

-Martin.

Is it better to set your read offset by ripping, burning, reripping, and using eac to compare the two tracks or should I go with the values accurate rip tells me? When I did this before I got accurate rip, I got different numbers than what accurate rip said I should have for my drive.

By the way, thank you for all your help!

To find your read offset correction then Accuraterip is a very good tool. If you try to do it with EAC then you will have to get the same result on a lot of discs because of the "different pressings" issue. When you use AccurateRip for it, then it will check if the found offset correction value of the inserted disc matches whats allready stored in its drive database and if it dosent you will then have to try another disc. Also if you have a drive that is not yet in the drive database then you will need to get 3 matching offsets on 3 discs for it to configure. Then for finding the write offset of your drive then i would make an offset test disc with EAC to find out what your combined read/write offset correction is, and with that and the previusly found read offset correction you can now determine your write offset. -Martin.