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Topic: AccurateRip/Foobar bit-compare result mismatch (Read 2654 times) previous topic - next topic

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AccurateRip/Foobar bit-compare result mismatch
i'm baffled. Here's what happened: I have this one CD that I ripped using EAC that is giving me some errors at the last track. I use "Copy image and create cuesheet" and the format is wavpack. I first ripped this on my computer and AccurateRip in EAC says all tracks were accurately ripped with confidence of 7. I then ripped the same CD on my brother's computer and again AccurateRip in EAC says all tracks were accurately ripped with the confidence of 7. Same checksums on all tracks, including the last track. However the CD image CRC was different and when I bit compare the last tracks of my computer's rip and my brother's rip using Foobar it says that differences found 

Long story short:

My computer's rip:
Code: [Select]
Peak level 98.8 %
     Range quality 99.9 %
     Copy CRC 46534B0A
     Copy OK

No errors occurred

 
AccurateRip summary
 
Track  1  accurately ripped (confidence 7)  [89850A3E]
Track  2  accurately ripped (confidence 7)  [669E3367]
Track  3  accurately ripped (confidence 7)  [71A47887]

All tracks accurately ripped


My brother's computer rip:
Code: [Select]
Peak level 98.8 %
     Extraction speed 7.8 X
     Range quality 99.9 %
     Copy CRC 5F979B80
     Copy OK

No errors occurred

 
AccurateRip summary
 
Track  1  accurately ripped (confidence 7)  [89850A3E]  (AR v1)
Track  2  accurately ripped (confidence 7)  [669E3367]  (AR v1)
Track  3  accurately ripped (confidence 7)  [71A47887]  (AR v1)
 
All tracks accurately ripped

Not the CRC difference between my pc's and my bro's pc's rips.

When I use "verify album with AccurateRip" in Foobar2000, my pc's rip says:
Code: [Select]
Track  Status
01    Accurately ripped, confidence: 7.
02    Accurately ripped, confidence: 7.
03    Accurately ripped, confidence: 7.

My brother's rip:
Code: [Select]
Track  Status
01    Accurately ripped with offset: -18(1).
02    Accurately ripped with offset: -18(1).
03    Accurately ripped with offset: -18(1).

Using bitcompare on the last tracks of both rips says:
Code: [Select]
Differences found: 54 sample(s), starting at 282.5593651 second(s), peak: 0.0000305 at 282.5593651 second(s), 1ch

Perhaps I'm missing something obvious here, how come two tracks that are both accurately ripped have differences when bit-compared against each other? The first two tracks return "No difference found" when bit-compared. Anyone can shed some light?

Thanks in advance

  • pdq
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AccurateRip/Foobar bit-compare result mismatch
Reply #1
AccurateRip CRCs omit the first few and last few frames on a CD. Apparently the differences are in the last few frames.

  • spoon
  • [*][*][*][*][*]
  • Administrator
AccurateRip/Foobar bit-compare result mismatch
Reply #2
...because drives have different offsets and not that many can overread to fetch the data which is lost to offset.

  • pdq
  • [*][*][*][*][*]
AccurateRip/Foobar bit-compare result mismatch
Reply #3
If you simply delete the frames that don't match then you will be sure of the accuracy of what remains, and I doubt that you could hear the difference because it is such a short time (1/75 second per frame).

AccurateRip/Foobar bit-compare result mismatch
Reply #4
I see. Thank you for the explanations! Make sense now, I was so confused.