Ripping accuracy

[nickitson]

Hi,

Just starting out with ripping my CD collection and have decided to try it with MusicBee. Very happy so far, but I have had some issues with some CDs. They all look undamaged, but the status messages I get for the tracks on some discs after encoding include 'inaccurately ripped', 'partially accurate rip' and one track labelled as having negligible errors (5 samples).

Can anyone tell me what the criteria and thresholds are for each of these status conditions and what that might mean for the ripped track in playback (both audible artefacts and stress on equipment)?

Any and all assistance appreciated.

[Steven]

'inaccurately ripped', 'partially accurate rip'  both mean the rip data does not match data submitted by other users to the accuraterip database. 'partially accurate rip' is not a good description and i might remove it. In both cases it is likely your rip does not match the data on the CD (but it might be just a few samples wrong - you have no way of knowing). If you always get this message for every rip, your CD drive read offset is probably set wrong.

It sounds like you also have secure ripping enabled which re-reads the ripped cd - "negligible errors (5 samples)" means it found 5 samples that were different. It would retry a number of times before it got exactly matching data or tell you it failed.

I have had the same with my CD device - sometimes the same CD in good quality will not rip accurately. Then weeks go by and its fine with the same CD.

[nickitson]

Hi,

Thanks for your prompt response. Your thoughts appreciated.

[PASTYL-FLO]

Hi, I have a similar problem with a CD I ripped today, but on previous days other CDs I've ripped have been verified as accurate. I'm sure my offset is set properly as well. Is this out of our control or is there something we can do to ensure accurate rips?

[vincent kars]

By design bit perfect reading of CDs is not guaranteed.
It can be done (CD ROM) but the additional error correction bits eats 10% of the capacity.
Hence audio CDS are not bit perfect by design but in practice due to all kind of tricks (8-14 modulation, interleaved Reed-Solomn, etc) they are most of the time “perfect”.
If not the interpolator takes care of the gaps.

Sometimes it helps if you clean them or try another drive.
A bit more can be found here: http://www.thewelltemperedcomputer.com/KB/Ripping.htm

[Russellc]

By design bit perfect reading of CDs is not guaranteed.
It can be done (CD ROM) but the additional error correction bits eats 10% of the capacity.
Hence audio CDS are not bit perfect by design but in practice due to all kind of tricks (8-14 modulation, interleaved Reed-Solomn, etc) they are most of the time “perfect”.
If not the interpolator takes care of the gaps.

Sometimes it helps if you clean them or try another drive.
A bit more can be found here: http://www.thewelltemperedcomputer.com/KB/Ripping.htm

Excellent read!

Russellc

[vincent kars]

Thanks

Vincent

[nobita]

Hi,

When I performed a binary comparison of the file that Exact Audio Copy displayed as "accurate rip" and the one that MusicBee displayed as "partially accurate rip", they matched perfectly.
Why is there a difference in AccurateRip results?
What is partially accurate rip?

Thanks

[phred]

What is partially accurate rip?

'inaccurately ripped', 'partially accurate rip'  both mean the rip data does not match data submitted by other users to the accuraterip database. 'partially accurate rip' is not a good description and i might remove it. In both cases it is likely your rip does not match the data on the CD (but it might be just a few samples wrong - you have no way of knowing). If you always get this message for every rip, your CD drive read offset is probably set wrong.

[wiggly1uk2000]

I can't answer your question but I have the same issue myself. If I rip certain CDs in MusicBee i end up with a partially accurate rip, even though they rip just fine using other software. I'm ripping to FLAC and whatever ripping settings I use I get the same problem, though not with all CDs.

Here's an example (below). It's the error report I get in PerfectTunes if I scan the rip afterwards. To be clear, this CD is original and undamaged. It rips fine using other software but not with MusicBee. I'd really like to figure out why. If it's a configuration problem then why is it not affecting all CD rips? Currently it means that I can't reliably use MusicBee for ripping purposes which is a shame because it's great for everything else!

Leo Sayer - The Gold Collection        Cannot Check: Track Different Length Than CD Original
  Track 1: E:\Music Temp\You Make Me Feel Like Dancing (7  Version).flac
  Track 2: E:\Music Temp\Thunder In My Heart.flac
  Track 3: E:\Music Temp\Long Tall Glasses (7  Version).flac
  Track 4: E:\Music Temp\The Show Must Go On (7  Version).flac
  Track 5: E:\Music Temp\Moonlight.flac
  Track 6: E:\Music Temp\I Will Not Stop Fighting.flac
  Track 7: E:\Music Temp\One Man Band.flac
  Track 8: E:\Music Temp\Why Is Everybody Going Home.flac
  Track 9: E:\Music Temp\Stormy Weather.flac
  Track 10: E:\Music Temp\Giving It All Away.flac
  Track 11: E:\Music Temp\Don't Wait Until Tomorrow.flac
  Track 12: E:\Music Temp\Train (Original 1974 Version).flac
  Track 13: E:\Music Temp\Living In A Fantasy.flac
  Track 14: E:\Music Temp\In My Life.flac
  Track 15: E:\Music Temp\Millionaire.flac
  Track 16: E:\Music Temp\When The Money Runs Out.flac
  Track 17: E:\Music Temp\World Radio.flac
  Track 18: E:\Music Temp\Thunder In My Heart Again (Radio Edit) [Meck feat. Leo Sayer].flac

[phred]

It's quite clear that the track lengths are different between what you ripped and what Perfect Tunes has in it's database. I have no idea how to tell which is correct, but if the "error" is only that the length of time is different, the actual music is fine.

[wiggly1uk2000]

It's quite clear that the track lengths are different between what you ripped and what Perfect Tunes has in it's database. I have no idea how to tell which is correct, but if the "error" is only that the length of time is different, the actual music is fine.

Indeed, but without verification of an accurate rip I can't be certain of why a track might not be deemed accurate, especially for CDs that are in poorer physical condition. It's not a huge problem but it's only natural to gravitate towards software that provides results that can be more easily verified in the Accurate Rip database. Here's the exact same CD album ripped using different software and checked afterwards in PerfectTunes...

Leo Sayer - The Gold Collection   [AccurateRip DiscIDs: 018-002C2634-02558F95-F5107012]
  Track 1: AccurateRip Verified Confidence 25, Pressing Offset +0 [ARv2 CRC 8563CBF0]  E:\FLAC Music Library\Leo Sayer - The Gold Collection\You Make Me Feel Like Dancing [7'' Version].flac
  Track 2: AccurateRip Verified Confidence 25, Pressing Offset +0 [ARv2 CRC 23D100E8]  E:\FLAC Music Library\Leo Sayer - The Gold Collection\Thunder In My Heart.flac
  Track 3: AccurateRip Verified Confidence 26, Pressing Offset +0 [ARv2 CRC B6E3B0BE]  E:\FLAC Music Library\Leo Sayer - The Gold Collection\Long Tall Glasses [7'' Version].flac
  Track 4: AccurateRip Verified Confidence 25, Pressing Offset +0 [ARv2 CRC B287CD0A]  E:\FLAC Music Library\Leo Sayer - The Gold Collection\The Show Must Go On [7'' Version].flac
  Track 5: AccurateRip Verified Confidence 25, Pressing Offset +0 [ARv2 CRC 7322A844]  E:\FLAC Music Library\Leo Sayer - The Gold Collection\Moonlighting.flac
  Track 6: AccurateRip Verified Confidence 24, Pressing Offset +0 [ARv2 CRC B30EC929]  E:\FLAC Music Library\Leo Sayer - The Gold Collection\I Will Not Stop Fighting.flac
  Track 7: AccurateRip Verified Confidence 25, Pressing Offset +0 [ARv2 CRC 590CF377]  E:\FLAC Music Library\Leo Sayer - The Gold Collection\One Man Band.flac
  Track 8: AccurateRip Verified Confidence 25, Pressing Offset +0 [ARv2 CRC 3716E493]  E:\FLAC Music Library\Leo Sayer - The Gold Collection\Why Is Everybody Going Home.flac
  Track 9: AccurateRip Verified Confidence 25, Pressing Offset +0 [ARv2 CRC 9528AD8C]  E:\FLAC Music Library\Leo Sayer - The Gold Collection\Stormy Weather.flac
  Track 10: AccurateRip Verified Confidence 25, Pressing Offset +0 [ARv2 CRC AB21BF47]  E:\FLAC Music Library\Leo Sayer - The Gold Collection\Giving It All Away.flac
  Track 11: AccurateRip Verified Confidence 25, Pressing Offset +0 [ARv2 CRC EAD7FA03]  E:\FLAC Music Library\Leo Sayer - The Gold Collection\Don't Wait Until Tomorrow.flac
  Track 12: AccurateRip Verified Confidence 25, Pressing Offset +0 [ARv2 CRC 3B4AF24D]  E:\FLAC Music Library\Leo Sayer - The Gold Collection\Train [Original 1974 Version].flac
  Track 13: AccurateRip Verified Confidence 25, Pressing Offset +0 [ARv2 CRC 6BE29812]  E:\FLAC Music Library\Leo Sayer - The Gold Collection\Living In A Fantasy.flac
  Track 14: AccurateRip Verified Confidence 25, Pressing Offset +0 [ARv2 CRC 9CDC104C]  E:\FLAC Music Library\Leo Sayer - The Gold Collection\In My Life.flac
  Track 15: AccurateRip Verified Confidence 25, Pressing Offset +0 [ARv2 CRC 46C8155F]  E:\FLAC Music Library\Leo Sayer - The Gold Collection\Millionaire.flac
  Track 16: AccurateRip Verified Confidence 25, Pressing Offset +0 [ARv2 CRC 66147AA0]  E:\FLAC Music Library\Leo Sayer - The Gold Collection\When The Money Runs Out.flac
  Track 17: AccurateRip Verified Confidence 24, Pressing Offset +0 [ARv2 CRC E2ECEB1C]  E:\FLAC Music Library\Leo Sayer - The Gold Collection\World Radio.flac
  Track 18: AccurateRip Verified Confidence 25, Pressing Offset +0 [ARv2 CRC D37F49A3]  E:\FLAC Music Library\Leo Sayer - The Gold Collection\Thunder In My Heart Again (Radio Edit) [Meck feat. Leo Sayer].flac

That's using the same CD, computer, optical drive (with the offset correctly set) and FLAC encoder. All that's different is the ripping software used.

I can confirm that the track lengths (and thus file sizes) are different for the same CD ripped in MusicBee when compared to the other software that I use. I wonder if MusicBee is defining the gaps between the tracks differently (or the start/end points for each track) and perhaps this hints at why only some CDs are affected. I should add that it doesn't help at all to change MusicBee's setting for pre-gap handling.

I'm no expert on the technicalities of Red Book but it seems to me that all CD ripping software ought to rip in the same manner and produce identical results, all available configuration options being equal. For now I'm happy to switch to different software for CD ripping but I hope that in time this apparent MusicBee issue might be addressed.