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Two different 'perfect' EAC rips of the same CD, how is it possible?.

I've ripped with EAC one CD using two different drives, resulting in two different 'perfect' logs:

The 1st log is:

Code: [Select]
Exact Audio Copy V1.3 from 2. September 2016

EAC extraction logfile from 1. May 2018, 19:37

The Pleasure Fuckers / For Your Pleasure [1995 Roto Records RT-012-CD]

Used drive  : HL-DT-STDVDRAM GH24LS50   Adapter: 1  ID: 1

Read mode               : Secure
Utilize accurate stream : Yes
Defeat audio cache      : Yes
Make use of C2 pointers : No

Read offset correction                      : 667
Overread into Lead-In and Lead-Out          : No
Fill up missing offset samples with silence : Yes
Delete leading and trailing silent blocks   : No
Null samples used in CRC calculations       : Yes
Used interface                              : Native Win32 interface for Win NT & 2000
Gap handling                                : Appended to previous track

Used output format              : User Defined Encoder
Selected bitrate                : 256 kBit/s
Quality                         : High
Add ID3 tag                     : No
Command line compressor         : D:\flac-1.3.2-win\win64\flac.exe
Additional command line options : -8 -e -V -T "ARTIST=%artist%" -T "TITLE=%title%" -T "ALBUM=%albumtitle%" -T "DATE=%year%" -T "TRACKNUMBER=%tracknr%" -T "GENRE=%genre%" -T "PERFORMER=%albuminterpret%" -T "COMPOSER=%composer%" %haslyrics%--tag-from-file=LYRICS="%lyricsfile%"%haslyrics% -T "ALBUMARTIST=%albumartist%" -T "DISCNUMBER=%cdnumber%" -T "TOTALDISCS=%totalcds%" -T "TOTALTRACKS=%numtracks%" -T "COMMENT=EAC 1.3 Burst Test&Copy + LITE-ON iHAS124 F + FLAC 1.3.2 64 bits Level 8" %source% -o %dest%


TOC of the extracted CD

     Track |   Start  |  Length  | Start sector | End sector
    ---------------------------------------------------------
        1  |  0:00.00 |  2:58.05 |         0    |    13354  
        2  |  2:58.05 |  2:22.20 |     13355    |    24024  
        3  |  5:20.25 |  3:11.25 |     24025    |    38374  
        4  |  8:31.50 |  4:03.05 |     38375    |    56604  
        5  | 12:34.55 |  2:15.17 |     56605    |    66746  
        6  | 14:49.72 |  2:29.30 |     66747    |    77951  
        7  | 17:19.27 |  3:02.45 |     77952    |    91646  
        8  | 20:21.72 |  1:48.15 |     91647    |    99761  
        9  | 22:10.12 |  3:14.70 |     99762    |   114381  
       10  | 25:25.07 |  2:41.18 |    114382    |   126474  
       11  | 28:06.25 |  2:58.42 |    126475    |   139866  
       12  | 31:04.67 |  3:19.05 |    139867    |   154796  
       13  | 34:23.72 |  2:43.10 |    154797    |   167031  
       14  | 37:07.07 |  3:27.23 |    167032    |   182579  


Track  1

     Filename E:\The Pleasure Fuckers - (1995) - For Your Pleasure [1995 Roto Records RT-012-CD] · [FLAC EAC]\01. That Girl.wav

     Pre-gap length  0:00:02.00

     Peak level 98.0 %
     Extraction speed 0.9 X
     Track quality 100.0 %
     Test CRC 98D3E157
     Copy CRC 98D3E157
     Track not present in AccurateRip database
     Copy OK

Track  2

     Filename E:\The Pleasure Fuckers - (1995) - For Your Pleasure [1995 Roto Records RT-012-CD] · [FLAC EAC]\02. Hungry Man.wav

     Pre-gap length  0:00:00.70

     Peak level 98.0 %
     Extraction speed 0.9 X
     Track quality 100.0 %
     Test CRC 8DEF7E99
     Copy CRC 8DEF7E99
     Track not present in AccurateRip database
     Copy OK

Track  3

     Filename E:\The Pleasure Fuckers - (1995) - For Your Pleasure [1995 Roto Records RT-012-CD] · [FLAC EAC]\03. Captain Igloo.wav

     Peak level 98.0 %
     Extraction speed 1.1 X
     Track quality 100.0 %
     Test CRC A0AAD060
     Copy CRC A0AAD060
     Track not present in AccurateRip database
     Copy OK

Track  4

     Filename E:\The Pleasure Fuckers - (1995) - For Your Pleasure [1995 Roto Records RT-012-CD] · [FLAC EAC]\04. 30 Seconds.wav

     Pre-gap length  0:00:00.38

     Peak level 98.0 %
     Extraction speed 1.2 X
     Track quality 100.0 %
     Test CRC F8BBD8DD
     Copy CRC F8BBD8DD
     Track not present in AccurateRip database
     Copy OK

Track  5

     Filename E:\The Pleasure Fuckers - (1995) - For Your Pleasure [1995 Roto Records RT-012-CD] · [FLAC EAC]\05. Watermouth.wav

     Pre-gap length  0:00:00.25

     Peak level 98.0 %
     Extraction speed 1.2 X
     Track quality 100.0 %
     Test CRC 7BF85EFF
     Copy CRC 7BF85EFF
     Track not present in AccurateRip database
     Copy OK

Track  6

     Filename E:\The Pleasure Fuckers - (1995) - For Your Pleasure [1995 Roto Records RT-012-CD] · [FLAC EAC]\06. Gin Blossom.wav

     Peak level 98.0 %
     Extraction speed 1.0 X
     Track quality 99.9 %
     Test CRC 7CE42C84
     Copy CRC 7CE42C84
     Track not present in AccurateRip database
     Copy OK

Track  7

     Filename E:\The Pleasure Fuckers - (1995) - For Your Pleasure [1995 Roto Records RT-012-CD] · [FLAC EAC]\07. Whisky Heights.wav

     Pre-gap length  0:00:00.22

     Peak level 98.0 %
     Extraction speed 1.1 X
     Track quality 99.9 %
     Test CRC 9560EB08
     Copy CRC 9560EB08
     Track not present in AccurateRip database
     Copy OK

Track  8

     Filename E:\The Pleasure Fuckers - (1995) - For Your Pleasure [1995 Roto Records RT-012-CD] · [FLAC EAC]\08. Papel Morao.wav

     Pre-gap length  0:00:01.17

     Peak level 98.0 %
     Extraction speed 1.0 X
     Track quality 99.9 %
     Test CRC B86FF368
     Copy CRC B86FF368
     Track not present in AccurateRip database
     Copy OK

Track  9

     Filename E:\The Pleasure Fuckers - (1995) - For Your Pleasure [1995 Roto Records RT-012-CD] · [FLAC EAC]\09. Last Smoke Last Dime.wav

     Pre-gap length  0:00:00.20

     Peak level 98.0 %
     Extraction speed 1.5 X
     Track quality 100.0 %
     Test CRC 338611C9
     Copy CRC 338611C9
     Track not present in AccurateRip database
     Copy OK

Track 10

     Filename E:\The Pleasure Fuckers - (1995) - For Your Pleasure [1995 Roto Records RT-012-CD] · [FLAC EAC]\10. Gone Around The Bend.wav

     Pre-gap length  0:00:01.27

     Peak level 98.0 %
     Extraction speed 1.4 X
     Track quality 100.0 %
     Test CRC F78EEDFE
     Copy CRC F78EEDFE
     Track not present in AccurateRip database
     Copy OK

Track 11

     Filename E:\The Pleasure Fuckers - (1995) - For Your Pleasure [1995 Roto Records RT-012-CD] · [FLAC EAC]\11. Masacre En El Disco Bar.wav

     Pre-gap length  0:00:00.33

     Peak level 98.0 %
     Extraction speed 1.5 X
     Track quality 100.0 %
     Test CRC 5071F9ED
     Copy CRC 5071F9ED
     Track not present in AccurateRip database
     Copy OK

Track 12

     Filename E:\The Pleasure Fuckers - (1995) - For Your Pleasure [1995 Roto Records RT-012-CD] · [FLAC EAC]\12. Sexy French Motherfucker.wav

     Pre-gap length  0:00:01.37

     Peak level 98.0 %
     Extraction speed 1.6 X
     Track quality 100.0 %
     Test CRC 672562D6
     Copy CRC 672562D6
     Track not present in AccurateRip database
     Copy OK

Track 13

     Filename E:\The Pleasure Fuckers - (1995) - For Your Pleasure [1995 Roto Records RT-012-CD] · [FLAC EAC]\13. Watermouth Part II.wav

     Pre-gap length  0:00:01.22

     Peak level 100.0 %
     Extraction speed 1.6 X
     Track quality 100.0 %
     Test CRC E82CAAA0
     Copy CRC E82CAAA0
     Track not present in AccurateRip database
     Copy OK

Track 14

     Filename E:\The Pleasure Fuckers - (1995) - For Your Pleasure [1995 Roto Records RT-012-CD] · [FLAC EAC]\14. Socio De Satan.wav

     Pre-gap length  0:00:00.52

     Peak level 98.0 %
     Extraction speed 1.8 X
     Track quality 100.0 %
     Test CRC 3AB7D24E
     Copy CRC 3AB7D24E
     Track not present in AccurateRip database
     Copy OK


None of the tracks are present in the AccurateRip database

No errors occurred

End of status report

---- CUETools DB Plugin V2.1.6

[CTDB TOCID: IpwODQACtcZQXEfrQ3eMnA9dG.o-] found
Submit result: already submitted
Track | CTDB Status
  1   | (3/3) Accurately ripped
  2   | (2/3) Accurately ripped
  3   | (3/3) Accurately ripped
  4   | (3/3) Accurately ripped
  5   | (3/3) Accurately ripped
  6   | (3/3) Accurately ripped
  7   | (3/3) Accurately ripped
  8   | (3/3) Accurately ripped
  9   | (3/3) Accurately ripped
 10   | (3/3) Accurately ripped
 11   | (3/3) Accurately ripped
 12   | (3/3) Accurately ripped
 13   | (3/3) Accurately ripped
 14   | (3/3) Accurately ripped


The 2nd log is:

Code: [Select]
Exact Audio Copy V1.3 from 2. September 2016

EAC extraction logfile from 2. May 2018, 12:20

The Pleasure Fuckers / For Your Pleasure [1995 Roto Records RT-012-CD]

Used drive  : ATAPI   iHAS124   F   Adapter: 1  ID: 0

Read mode               : Secure
Utilize accurate stream : Yes
Defeat audio cache      : Yes
Make use of C2 pointers : No

Read offset correction                      : 6
Overread into Lead-In and Lead-Out          : No
Fill up missing offset samples with silence : Yes
Delete leading and trailing silent blocks   : No
Null samples used in CRC calculations       : Yes
Used interface                              : Native Win32 interface for Win NT & 2000
Gap handling                                : Appended to previous track

Used output format              : User Defined Encoder
Selected bitrate                : 256 kBit/s
Quality                         : High
Add ID3 tag                     : No
Command line compressor         : D:\flac-1.3.2-win\win64\flac.exe
Additional command line options : -8 -e -V -T "ARTIST=%artist%" -T "TITLE=%title%" -T "ALBUM=%albumtitle%" -T "DATE=%year%" -T "TRACKNUMBER=%tracknr%" -T "GENRE=%genre%" -T "PERFORMER=%albuminterpret%" -T "COMPOSER=%composer%" %haslyrics%--tag-from-file=LYRICS="%lyricsfile%"%haslyrics% -T "ALBUMARTIST=%albumartist%" -T "DISCNUMBER=%cdnumber%" -T "TOTALDISCS=%totalcds%" -T "TOTALTRACKS=%numtracks%" -T "COMMENT=EAC 1.3 Burst Test&Copy + LITE-ON iHAS124 F + FLAC 1.3.2 64 bits Level 8" %source% -o %dest%


TOC of the extracted CD

     Track |   Start  |  Length  | Start sector | End sector
    ---------------------------------------------------------
        1  |  0:00.00 |  2:58.05 |         0    |    13354  
        2  |  2:58.05 |  2:22.20 |     13355    |    24024  
        3  |  5:20.25 |  3:11.25 |     24025    |    38374  
        4  |  8:31.50 |  4:03.05 |     38375    |    56604  
        5  | 12:34.55 |  2:15.17 |     56605    |    66746  
        6  | 14:49.72 |  2:29.30 |     66747    |    77951  
        7  | 17:19.27 |  3:02.45 |     77952    |    91646  
        8  | 20:21.72 |  1:48.15 |     91647    |    99761  
        9  | 22:10.12 |  3:14.70 |     99762    |   114381  
       10  | 25:25.07 |  2:41.18 |    114382    |   126474  
       11  | 28:06.25 |  2:58.42 |    126475    |   139866  
       12  | 31:04.67 |  3:19.05 |    139867    |   154796  
       13  | 34:23.72 |  2:43.10 |    154797    |   167031  
       14  | 37:07.07 |  3:27.23 |    167032    |   182579  


Track  1

     Filename E:\The Pleasure Fuckers - (1995) - For Your Pleasure [1995 Roto Records RT-012-CD] · [FLAC EAC]\01. That Girl.wav

     Pre-gap length  0:00:02.00

     Peak level 98.0 %
     Extraction speed 3.1 X
     Track quality 100.0 %
     Test CRC 98D3E157
     Copy CRC 98D3E157
     Track not present in AccurateRip database
     Copy OK

Track  2

     Filename E:\The Pleasure Fuckers - (1995) - For Your Pleasure [1995 Roto Records RT-012-CD] · [FLAC EAC]\02. Hungry Man.wav

     Pre-gap length  0:00:00.70

     Peak level 98.0 %
     Extraction speed 3.3 X
     Track quality 100.0 %
     Test CRC 92DB46A1
     Copy CRC 92DB46A1
     Track not present in AccurateRip database
     Copy OK

Track  3

     Filename E:\The Pleasure Fuckers - (1995) - For Your Pleasure [1995 Roto Records RT-012-CD] · [FLAC EAC]\03. Captain Igloo.wav

     Peak level 98.0 %
     Extraction speed 3.8 X
     Track quality 100.0 %
     Test CRC A0AAD060
     Copy CRC A0AAD060
     Track not present in AccurateRip database
     Copy OK

Track  4

     Filename E:\The Pleasure Fuckers - (1995) - For Your Pleasure [1995 Roto Records RT-012-CD] · [FLAC EAC]\04. 30 Seconds.wav

     Pre-gap length  0:00:00.38

     Peak level 98.0 %
     Extraction speed 4.2 X
     Track quality 100.0 %
     Test CRC F8BBD8DD
     Copy CRC F8BBD8DD
     Track not present in AccurateRip database
     Copy OK

Track  5

     Filename E:\The Pleasure Fuckers - (1995) - For Your Pleasure [1995 Roto Records RT-012-CD] · [FLAC EAC]\05. Watermouth.wav

     Pre-gap length  0:00:00.25

     Peak level 98.0 %
     Extraction speed 4.0 X
     Track quality 100.0 %
     Test CRC 7BF85EFF
     Copy CRC 7BF85EFF
     Track not present in AccurateRip database
     Copy OK

Track  6

     Filename E:\The Pleasure Fuckers - (1995) - For Your Pleasure [1995 Roto Records RT-012-CD] · [FLAC EAC]\06. Gin Blossom.wav

     Peak level 98.0 %
     Extraction speed 3.1 X
     Track quality 99.9 %
     Test CRC 7CE42C84
     Copy CRC 7CE42C84
     Track not present in AccurateRip database
     Copy OK

Track  7

     Filename E:\The Pleasure Fuckers - (1995) - For Your Pleasure [1995 Roto Records RT-012-CD] · [FLAC EAC]\07. Whisky Heights.wav

     Pre-gap length  0:00:00.22

     Peak level 98.0 %
     Extraction speed 3.6 X
     Track quality 99.9 %
     Test CRC 9560EB08
     Copy CRC 9560EB08
     Track not present in AccurateRip database
     Copy OK

Track  8

     Filename E:\The Pleasure Fuckers - (1995) - For Your Pleasure [1995 Roto Records RT-012-CD] · [FLAC EAC]\08. Papel Morao.wav

     Pre-gap length  0:00:01.17

     Peak level 98.0 %
     Extraction speed 3.0 X
     Track quality 99.9 %
     Test CRC B86FF368
     Copy CRC B86FF368
     Track not present in AccurateRip database
     Copy OK

Track  9

     Filename E:\The Pleasure Fuckers - (1995) - For Your Pleasure [1995 Roto Records RT-012-CD] · [FLAC EAC]\09. Last Smoke Last Dime.wav

     Pre-gap length  0:00:00.20

     Peak level 98.0 %
     Extraction speed 5.0 X
     Track quality 100.0 %
     Test CRC 338611C9
     Copy CRC 338611C9
     Track not present in AccurateRip database
     Copy OK

Track 10

     Filename E:\The Pleasure Fuckers - (1995) - For Your Pleasure [1995 Roto Records RT-012-CD] · [FLAC EAC]\10. Gone Around The Bend.wav

     Pre-gap length  0:00:01.27

     Peak level 98.0 %
     Extraction speed 5.0 X
     Track quality 100.0 %
     Test CRC F78EEDFE
     Copy CRC F78EEDFE
     Track not present in AccurateRip database
     Copy OK

Track 11

     Filename E:\The Pleasure Fuckers - (1995) - For Your Pleasure [1995 Roto Records RT-012-CD] · [FLAC EAC]\11. Masacre En El Disco Bar.wav

     Pre-gap length  0:00:00.33

     Peak level 98.0 %
     Extraction speed 5.3 X
     Track quality 100.0 %
     Test CRC 5071F9ED
     Copy CRC 5071F9ED
     Track not present in AccurateRip database
     Copy OK

Track 12

     Filename E:\The Pleasure Fuckers - (1995) - For Your Pleasure [1995 Roto Records RT-012-CD] · [FLAC EAC]\12. Sexy French Motherfucker.wav

     Pre-gap length  0:00:01.37

     Peak level 98.0 %
     Extraction speed 5.6 X
     Track quality 100.0 %
     Test CRC 672562D6
     Copy CRC 672562D6
     Track not present in AccurateRip database
     Copy OK

Track 13

     Filename E:\The Pleasure Fuckers - (1995) - For Your Pleasure [1995 Roto Records RT-012-CD] · [FLAC EAC]\13. Watermouth Part II.wav

     Pre-gap length  0:00:01.22

     Peak level 100.0 %
     Extraction speed 5.5 X
     Track quality 100.0 %
     Test CRC E82CAAA0
     Copy CRC E82CAAA0
     Track not present in AccurateRip database
     Copy OK

Track 14

     Filename E:\The Pleasure Fuckers - (1995) - For Your Pleasure [1995 Roto Records RT-012-CD] · [FLAC EAC]\14. Socio De Satan.wav

     Pre-gap length  0:00:00.52

     Peak level 98.0 %
     Extraction speed 5.9 X
     Track quality 100.0 %
     Test CRC 3AB7D24E
     Copy CRC 3AB7D24E
     Track not present in AccurateRip database
     Copy OK


None of the tracks are present in the AccurateRip database

No errors occurred

End of status report

---- CUETools DB Plugin V2.1.6

[CTDB TOCID: IpwODQACtcZQXEfrQ3eMnA9dG.o-] found
Submit result: already submitted
Track | CTDB Status
  1   | (3/3) Accurately ripped
  2   | (1/3) Accurately ripped, or (2/3) differs in 4 samples @00:28:29
  3   | (3/3) Accurately ripped
  4   | (3/3) Accurately ripped
  5   | (3/3) Accurately ripped
  6   | (3/3) Accurately ripped
  7   | (3/3) Accurately ripped
  8   | (3/3) Accurately ripped
  9   | (3/3) Accurately ripped
 10   | (3/3) Accurately ripped
 11   | (3/3) Accurately ripped
 12   | (3/3) Accurately ripped
 13   | (3/3) Accurately ripped
 14   | (3/3) Accurately ripped
If you are sure that your rip contains errors, you can use CUETools to repair it.

The problem is that for Track 2 the obtained CRCs are different in both logs:

CRC for Track 2 @ 1st log:

Track  2

     Filename E:\The Pleasure Fuckers - (1995) - For Your Pleasure [1995 Roto Records RT-012-CD] · [FLAC EAC]\02. Hungry Man.wav
     Pre-gap length  0:00:00.70
     Peak level 98.0 %
     Extraction speed 0.9 X
     Track quality 100.0 %
     Test CRC 8DEF7E99
     Copy CRC 8DEF7E99

     Track not present in AccurateRip database
     Copy OK


CRC for Track 2 @ 2nd log:

Track  2

     Filename E:\The Pleasure Fuckers - (1995) - For Your Pleasure [1995 Roto Records RT-012-CD] · [FLAC EAC]\02. Hungry Man.wav
     Pre-gap length  0:00:00.70
     Peak level 98.0 %
     Extraction speed 3.3 X
     Track quality 100.0 %
     Test CRC 92DB46A1
     Copy CRC 92DB46A1

     Track not present in AccurateRip database
     Copy OK


Comparing the audio data in both tracks (with the foobar2000 bit-compare plug-in), it happens that there is a 4 sample difference:

Code: [Select]
Comparing:
"E:\Buffer\A\02. Hungry Man.flac"
"E:\Buffer\B\02. Hungry Man.flac"
Compared 6273960 samples.
Differences found: 4 values, starting at 0:28.392925, peak: 0.0916138 at 0:28.392925, 1ch
Channel difference peaks: 0.0916138 0.0146790
File #1 peaks: 0.9803162 0.9801025
File #2 peaks: 0.9803162 0.9801025
Detected offset as 0 samples.

How is it possible to obtain two different 'perfect' rips of the same CD?. If both extractions are 'perfect', which one is the good one?

I'm a little bit shocked and confused with this result.

Some ideas?

Thanks in advance.

Re: Two different 'perfect' EAC rips of the same CD, how is it possible?.

Reply #1
"Perfect" just means that EAC always got the same result when reading those samples with each drive. There's no AccurateRip entry for that CD but CTDB reports 3 rips. Assuming the other 2 aren't also your own submissions, personally I'd go with the first rip, as it agreed with the other 2.

Try a burst test & copy with both drives in EAC, and try CUERipper too.

 

Re: Two different 'perfect' EAC rips of the same CD, how is it possible?.

Reply #2
All 3 CTDB results are from the OP. Once with the GH24LS50 drive. Once with the iHAS124 drive (all tracks matching the rip from the GH24LS50 drive). Once with the iHAS124 drive (4 samples differ on track 2).

https://dbpoweramp.com/spoons-audio-guide-cd-ripping.htm
Quote
Secure Ripping
[...]
Re-Reading
CD is read twice, if a section contains an error it will likely return different errors, so can be detected. This is true mostly but not always, consistent errors exist...
It is possible for one drive to consistently read the 4 samples one way while the other drive consistently reads them another. One possible explanation is that the CD has a minor manufacturing flaw causing this behavior.

As for "which one is the good one? "
Either, neither, but can you hear a difference?
korth

Re: Two different 'perfect' EAC rips of the same CD, how is it possible?.

Reply #3
I have seen this; it is not all that unusual.  Majority rule is a stupid way to choose.

Personally, I would load each version into Adobe Audition duplicate one version and subtract the other version from the duplicate version.  Zoom in on the difference and mark with cue points.  Load all three in the multitrack editor, select over the range marked by the cue points and look at each track.  You will most likely see linear interpolation on the bad track.  Keep the other track.

I normally don't field these types of questions anymore, but since there is a much more definitive way I thought I'd share it.  Hopefully this information will be passed along.
Is 24-bit/192kHz good enough for your lo-fi vinyl, or do you need 32/384?

Re: Two different 'perfect' EAC rips of the same CD, how is it possible?.

Reply #4
All 3 CTDB results are from the OP. Once with the GH24LS50 drive. Once with the iHAS124 drive (all tracks matching the rip from the GH24LS50 drive). Once with the iHAS124 drive (4 samples differ on track 2).

Yes, all CTDB results are mine, from previous test extractions. All of which consistently yielded the same 4 sample difference.

https://dbpoweramp.com/spoons-audio-guide-cd-ripping.htm
Quote
Secure Ripping
[...]
Re-Reading
CD is read twice, if a section contains an error it will likely return different errors, so can be detected. This is true mostly but not always, consistent errors exist...
It is possible for one drive to consistently read the 4 samples one way while the other drive consistently reads them another. One possible explanation is that the CD has a minor manufacturing flaw causing this behavior.

Ok, Thanks, at least I know that this can happen.

As for "which one is the good one? "
Either, neither, but can you hear a difference?

Probably not, is just that I was curious and confused about this strange behavior  ;)

Re: Two different 'perfect' EAC rips of the same CD, how is it possible?.

Reply #5
I have seen this; it is not all that unusual.  Majority rule is a stupid way to choose.

Personally, I would load each version into Adobe Audition duplicate one version and subtract the other version from the duplicate version.  Zoom in on the difference and mark with cue points.  Load all three in the multitrack editor, select over the range marked by the cue points and look at each track.  You will most likely see linear interpolation on the bad track.  Keep the other track.

I normally don't field these types of questions anymore, but since there is a much more definitive way I thought I'd share it.  Hopefully this information will be passed along.

Great. I will try to do it as soon as I have some free time. I will post the results.

Thank you very much  :) 


Re: Two different 'perfect' EAC rips of the same CD, how is it possible?.

Reply #6
You can also generate spectrograms of sufficient resolution of both files, making sure they are time-aligned first (which they are in this case), and compare them. The tool of my choice would be SoX, as it gives consistent zoom level (specified with -X). Interpolated samples will show up as lines near the nyquist frequency, which will stand out if those are the only differences. This method also works if the waveform happens to be too chaotic to see a faint click or an interpolated segment.

Re: Two different 'perfect' EAC rips of the same CD, how is it possible?.

Reply #7
Thank you, I will try that too. I suppose you mean Nyquist Frequency = 44.1 / 2 = 22.05 kHz.

You can also generate spectrograms of sufficient resolution of both files, making sure they are time-aligned first (which they are in this case), and compare them. The tool of my choice would be SoX, as it gives consistent zoom level (specified with -X). Interpolated samples will show up as lines near the nyquist frequency, which will stand out if those are the only differences. This method also works if the waveform happens to be too chaotic to see a faint click or an interpolated segment.

Re: Two different 'perfect' EAC rips of the same CD, how is it possible?.

Reply #8
Depending on how the compressed the content is, there may already be a sea of lines near Nyquist, making it difficult to identify any additional ones.

I have found it quite easy to spot interpolation in chaotic waveforms, perhaps more so than less chaotic waveforms.  It is also extremely easy to look at the values of the sample in question as well as its neighbors to determine if they are interpolated.
Is 24-bit/192kHz good enough for your lo-fi vinyl, or do you need 32/384?

Re: Two different 'perfect' EAC rips of the same CD, how is it possible?.

Reply #9
Depending on how the compressed the content is, there may already be a sea of lines near Nyquist, making it difficult to identify any additional ones.

I have found it quite easy to spot interpolation in chaotic waveforms, perhaps more so than less chaotic waveforms.  It is also extremely easy to look at the values of the sample in question as well as its neighbors to determine if they are interpolated.

Yes. In this case it's only a 4 samples anomaly, so it should be easy to detect artifacts just by inspecting the numerical value of the suspicious samples.


 
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