AccurateRip question

[mathmat]

Hi. I am new to this forum and just discovered PerfectTUNES when I was searching for a way to verify my Apple Lossless rips. I have a few questions about some of the results I got. Please keep in mind that I am new to the audiophile world and not too well-versed in audio jargon.

First, I checked about 30 CDs with PerfectTUNES and when I looked at the match details I noticed a few things that caused me to wonder. Approximately 40% of the CDs came back with 2 or more AccurateRip DiscIDs. From what I have seen around in various forums, as well as when I used CUETools to check these rips (Prior to discovering PerfectTunes, which I like much better. :smile2 I was under the assumption that each CD has only one ID. In the match details it does say "AccurateRip DiscIDs" (plural) so that makes me think there could be more than 1 for each CD. So I am confused. Anyway, I will post some of the results:

Rush - Moving Pictures [AccurateRip DiscIDs: 007-000AB2B1-004138E5-51096207 007-000B098C-00429FC1-59096207]

Iron Maiden - Powerslave [AccurateRip DiscIDs: 008-000E88EB-0066551D-6C10B009 008-000D1DE7-005991F9-590BD908 008-000E8981-00665A63-6C10B209 008-000E897F-00665A51-6C10B209]

I was just curious why there are more than 1 DiscIDs for approximately 40% of the CDs I ripped? For example, 2 in the case of Moving Pictures, and 4 in the case of Powerslave. Again I am new to all this and was hoping someone could explain to me the reasons. Preferably in simple layman's terms. :smile:


Second, all the CDs I ripped, when checked against AccurateRip using PerfectTUNES, have a pressing offset. (I'm still trying to understand fully what is meant by "offset.") I'm guessing it has something to do with the fact that I used iTunes to rip my CDs? I cross checked these with the results I got earlier through CUETools, and all but 1 CD had the "offsetted by xxxx" listing which matched what PerfectTUNES said about each track, that is, if it was verified or not. (Only 1 CD did not have the corresponding offset value table in CUETools and I'm not sure why.) But all the CDs I checked with PerfectTUNES came back with the same pressing offset for each track, with the exception of 1 CD. I will put it here. (Track 4 has a different offset than the other tracks and it is the only CD that doesn't have all the tracks with the same offset value.)


Led Zeppelin - Houses Of The Holy (AL) [AccurateRip DiscIDs: 008-000D04E0-005565B9-60099608 008-000D03C0-0055601A-5E099508]
Track 1: Track InAccurate C:\Users\A\Desktop\Lossless CD Rips\Led Zeppelin\Houses Of The Holy (AL)\01 The Song Remains The Same.m4a
Track 2: AccurateRip Verified Confidence 86, Pressing Offset +1396 [ARv2 CRC 83FBB633] C:\Users\A\Desktop\Lossless CD Rips\Led Zeppelin\Houses Of The Holy (AL)\02 The Rain Song.m4a
Track 3: AccurateRip Verified Confidence 86, Pressing Offset +1396 [ARv2 CRC 5BDB4B9D] C:\Users\A\Desktop\Lossless CD Rips\Led Zeppelin\Houses Of The Holy (AL)\03 Over The Hills And Far Away.m4a
Track 4: AccurateRip Verified Confidence 66, Pressing Offset +102 [ARv2 CRC D20E9798] C:\Users\A\Desktop\Lossless CD Rips\Led Zeppelin\Houses Of The Holy (AL)\04 The Crunge.m4a
Track 5: AccurateRip Verified Confidence 87, Pressing Offset +1396 [ARv2 CRC 3B070617] C:\Users\A\Desktop\Lossless CD Rips\Led Zeppelin\Houses Of The Holy (AL)\05 Dancing Days.m4a
Track 6: AccurateRip Verified Confidence 87, Pressing Offset +1396 [ARv2 CRC 21AE486A] C:\Users\A\Desktop\Lossless CD Rips\Led Zeppelin\Houses Of The Holy (AL)\06 D'Yer Mak'er.m4a
Track 7: AccurateRip Verified Confidence 87, Pressing Offset +1396 [ARv2 CRC 31D34DBD] C:\Users\A\Desktop\Lossless CD Rips\Led Zeppelin\Houses Of The Holy (AL)\07 No Quarter.m4a
Track 8: AccurateRip Verified Confidence 88, Pressing Offset +1396 [ARv2 CRC 55419277] C:\Users\A\Desktop\Lossless CD Rips\Led Zeppelin\Houses Of The Holy (AL)\08 The Ocean.m4a

Also this is another CD with 2 AccurateRip DiscIDs. Actually, all my Led Zeppelin CDs came back with 2.

Anyway, I was desperately hoping for any feedback regarding my 2 questions. I just want to be sure that my rips are accurate.

Thank you very much!

[garym]

Re: AccurateRip question

yes, your rips are accurate! I'll have to let Spoon chime in with the technical details as to why there are multiple AR IDs. I'm not sure if this relates to the fact that there was the original AR and now AR2 or something else, but it is normal nonetheless. Regarding offset, different pressings of batches of CDs from the manufacturing plant sometimes used different offsets on the disc. AccurateRip recognizes and considers this information in looking for a match. You may find this useful:

http://www.accuraterip.com/

[Spoon]

Re: AccurateRip question

The CD Ripper uses the track lengths + extra details, such as disc offset and data track. When looking up just using the files, it has to match on track lengths, an ID could be for an unrelated disc, this does not matter as it would never match.

[mathmat]

Re: AccurateRip question

Thank you very much to garym and Spoon! I appreciate your quick response! :smile:

So the reason I have more than 1 DiscID for some rips is because I was verifying against tracks that were ripped a long time ago and there is no CD information anymore? If that is the case then if I had used another CD ripping program other than iTunes I would be able to get more information from the CD prior to sending the rips to the AccurateRip database and consequently have only 1 DiscID? But as long as I have "Accurately Verified" (when using PerfectTUNES) for tracks even for 2 more Disc IDS I still have correctly ripped tracks, correct?


For the case of the Houses of the Holy CD I posted above, was AccurateRip comparing it against 2 different pressings since 6 tracks had an offet of +1396 and 1 had an offset of +102? (Track *1 came back as InAccurate, which I knew before checking it. But I just wanted to check the other tracks to make sure they were ripped accurately.) I don't understand what is hapening here. I don't understand why 1 track has a different offset from the others. Shouldn't all tracks on a CD have the same offset value? This was the only CD I verified that had this discrepancy. All other CDs I checked had the same offset value for all tracks. I would think that all tracks on a CD would have the same identical offset value, but, as I mentioned, I am new to this and coming to this forum because people here know what they are talking about. :smile:

Any clarification is tremendously appreciated!

And I have one other question concerning a discrepancy between PerfectTUnes and CUETools As I mentioned in my original post, every CD I verified with PT had a matching offset value in a prior compare I did with CUETools, and the Accuracy results were the same for all. But one CD I ripped didn't match. I'll post the PT results and then the CUETools results:


Pink Floyd - Dark Side Of The Moon [AccurateRip DiscIDs: 009-000F86F4-0072C539-710A1109 009-000F85B4-0072BE5A-6F0A1109]
Track 1: AccurateRip Verified Confidence 141, Pressing Offset -893 [ARv2 CRC 277D87CB] C:\Users\A\Desktop\Lossless CD Rips\pf alac\Dark Side Of The Moon\01 Speak To Me_Breathe.m4a
Track 2: AccurateRip Verified Confidence 141, Pressing Offset -893 [ARv2 CRC 63547C5D] C:\Users\A\Desktop\Lossless CD Rips\pf alac\Dark Side Of The Moon\02 On The Run.m4a
Track 3: AccurateRip Verified Confidence 142, Pressing Offset -893 [ARv2 CRC 1740BA5D] C:\Users\A\Desktop\Lossless CD Rips\pf alac\Dark Side Of The Moon\03 Time.m4a
Track 4: AccurateRip Verified Confidence 138, Pressing Offset -893 [ARv2 CRC 3A6FC960] C:\Users\A\Desktop\Lossless CD Rips\pf alac\Dark Side Of The Moon\04 The Great Gig In The Sky.m4a
Track 5: AccurateRip Verified Confidence 144, Pressing Offset -893 [ARv2 CRC 59E1676D] C:\Users\A\Desktop\Lossless CD Rips\pf alac\Dark Side Of The Moon\05 Money.m4a
Track 6: AccurateRip Verified Confidence 142, Pressing Offset -893 [ARv2 CRC 7EEB700C] C:\Users\A\Desktop\Lossless CD Rips\pf alac\Dark Side Of The Moon\06 Us And Them.m4a
Track 7: AccurateRip Verified Confidence 141, Pressing Offset -893 [ARv2 CRC E277234D] C:\Users\A\Desktop\Lossless CD Rips\pf alac\Dark Side Of The Moon\07 Any Colour You Like.m4a
Track 8: AccurateRip Verified Confidence 142, Pressing Offset -893 [ARv2 CRC C4DCCAB3] C:\Users\A\Desktop\Lossless CD Rips\pf alac\Dark Side Of The Moon\08 Brain Damage.m4a
Track 9: AccurateRip Verified Confidence 142, Pressing Offset -893 [ARv2 CRC 3EB4CFBC] C:\Users\A\Desktop\Lossless CD Rips\pf alac\Dark Side Of The Moon\09 Eclipse.m4a


[CUETools log; Date: 12/12/2014 12:54:23 PM; Version: 2.1.5]
[CTDB TOCID: PMerapu8APQFpRcsJSYs0Uyq7w8-] found.
Track | CTDB Status
1 | (55/57) Accurately ripped
2 | (54/57) Accurately ripped
3 | (54/57) Accurately ripped
4 | (53/57) Accurately ripped
5 | (54/57) Accurately ripped
6 | (54/57) Accurately ripped
7 | (55/57) Accurately ripped
8 | (55/57) Accurately ripped
9 | (55/57) Accurately ripped
[AccurateRip ID: 000f85b4-0072be5a-6f0a1109] found.
Track [ CRC | V2 ] Status
01 [76736a2a|72544ba1] (0+0/2) No match
02 [e1306833|599b75ef] (0+0/2) No match
03 [3b9f0271|4effc685] (0+0/2) No match
04 [549ac2b6|eb15e453] (0+0/7) No match
05 [cd1ea28c|6cf5d0ae] (0+0/8) No match
06 [4a102c12|299621be] (0+0/7) No match
07 [f26cd1f7|e5355e05] (0+0/7) No match
08 [f877302b|b3ee1e4f] (0+0/7) No match
09 [068d3cec|3ed65d36] (0+0/7) No match
Offsetted by 102:
01 [f8342f2d] (2/2) Accurately ripped
02 [d1a0ab20] (2/2) Accurately ripped
03 [f7b7992e] (2/2) Accurately ripped
04 [3f6c35a7] (1/7) Accurately ripped
05 [99341419] (1/8) Accurately ripped
06 [10dc1aea] (1/7) Accurately ripped
07 [a8f04a58] (1/7) Accurately ripped
08 [be8f1035] (1/7) Accurately ripped
09 [2e454b6a] (1/7) Accurately ripped
Offsetted by -2047:
01 [08682302] (0/2) No match
02 [34c80414] (0/2) No match
03 [73e86244] (0/2) No match
04 [6b145129] (0/7) No match
05 [55e9589a] (1/8) Accurately ripped
06 [9603d79a] (1/7) Accurately ripped
07 [4f45a852] (1/7) Accurately ripped
08 [beb0576e] (1/7) Accurately ripped
09 [8e768445] (1/7) Accurately ripped
Offsetted by -890:
01 [dd8594e2] (0/2) No match
02 [b6ccf62f] (0/2) No match
03 [5d50b566] (0/2) No match
04 [8f08a726] (1/7) Accurately ripped
05 [b80db480] (1/8) Accurately ripped
06 [47137bdb] (1/7) Accurately ripped
07 [5a02202d] (1/7) Accurately ripped
08 [8f15b1af] (1/7) Accurately ripped
09 [c4f9d7a8] (1/7) Accurately ripped
Offsetted by 84:
01 [a1ef2030] (0/2) No match
02 [d82983f5] (0/2) No match
03 [282a5931] (0/2) No match
04 [3359ffb1] (0/7) No match
05 [24ad8774] (1/8) Accurately ripped
06 [ab8c4105] (0/7) No match
07 [e7a6b6b4] (0/7) No match
08 [0a57dc8a] (0/7) No match
09 [0a21a6fe] (0/7) No match
Offsetted by 1628:
01 [aa5555e2] (0/2) No match
02 [9601461c] (0/2) No match
03 [b2b9f28f] (0/2) No match
04 [040ec12b] (0/7) No match
05 [37e4ac1a] (1/8) Accurately ripped
06 [ad770698] (0/7) No match
07 [90b73bc6] (0/7) No match
08 [18cf0053] (1/7) Accurately ripped
09 [74afb2d9] (1/7) Accurately ripped

Track Peak [ CRC32 ] [W/O NULL]
-- 96.8 [73738E88] [DF6AC392]
01 67.9 [3065EDFB] [E50BAC69]
02 69.1 [96EFC018] [F81A1E79]
03 76.9 [22806D0E] [E59E3414]
04 75.0 [821EEE04] [1A7C68D2]
05 96.8 [FE2C118F] [23EA32C9]
06 69.6 [82569275] [7555D9F0]
07 89.3 [4A97F2E4] [26624066]
08 75.7 [60F337F7] [8306140B]
09 82.5 [0509E34E] [2CD86E3C]

As you can see the -893 offset given by PT does not appear anywhere in the CUETools report. The closest is a -890 offset.

Just curious what is happening here, as this is the only CD I checked that didn't have the offset given by PT in the CUETools report.

Thank you again very much for any help and sorry if I am a bother. I'm just very particular when it comes to my music and I'd like some peace of mind that my collection is correctly ripped. I think that PT gives a much more user friendly result than CUETools and I just trust it more (not to mention being MUCH easier to use) but this discrepancy bothers me.

Thank you.

[garym]

Re: AccurateRip question

First, yes, what you are seeing is that these rips are confirmed as accurate based on AR database. I think your hypotheses re the CD DiskID is not correct (go back and reread Spoon's original answer to you on this question). Regarding the other things, CueTools, and EAC, and foobar2000 utilities that check AR matches don't all handle things exactly the same way. I think cuetools may be reporting all the possible matches to your CD diskID. PerfectTunes is smart enough to know that some of those are irrelevant. Not sure why only one track would have a different offset. I have seen this before too. Maybe spoon can answer that one.

Do keep in mind that PerfectTunes is an Illustrate product (as is dbpoweramp for ripping/converting). The AccurateRip database matching concept was created by Illustrate (i.e., Spoon). The AR database is managed by Illustrate. So while other rippers/converters etc. can use AccurateRip, I put my trust into the dbpa and PerfectTunes reports because the are produced by the folks that invented and maintain AccurateRip.

[Spoon]

Re: AccurateRip question

CueTools will not check pressing offsets with the new AccurateRip v2 CRC, dBpoweramp and PerfectTUNEs will.

[mathmat]

Re: AccurateRip question

Thank you again garym. I really appreciate your help. I guess I didn't understand Spoon's reply regarding the IDs. Like I said I'm new to all this and just trying to learn.

But as long as it's normal to have more than 1 ID for a CD, and if the tracks all come back as Accurate, then I can safely assume I have a accurately ripped CD, correct?

I agree with you about putting my trust in PerfectTUNES. For some reason I don't entirely trust CUETools. (For example, it wouldn't even read my Houses of the Holy with the corrupt Track 1, whereas PerfectTUNES did!) PerfectTUNES is the program I've been looking for for YEARS! It's amazing. I just wish I understood the technical aspects more. Like I said as long as the rips are accurate I'm happy. But being a stickler for perfection and understanding I tend to try to understand what is happening and why...

It's also encouraging that you have also seen one track have a different offset value than the other tracks in a particular CD. But I'd like to understand why that's happening,

Again, thank you garym, and any more feedback is appreciated TREMENDOUSLY! :smile:

[garym]

Re: AccurateRip question

But as long as it's normal to have more than 1 ID for a CD, and if the tracks all come back as Accurate, then I can safely assume I have a accurately ripped CD, correct?

yes. you have an accurately ripped CD! See spoon's response that showed up a minute ago about the cuetools differences. It all has to do with the additional benefits provided by AR2, which cuetools doesn't currently incorporate. PerfectTunes and dbpoweramp are the gold standard if you want secure rips. By the way, I suggest you quit ripping with itunes (which is not a secure ripper, although 99% of its rips are probably secure anyhow) and start ripping your CDs with dbpoweramp. The good news is that with the advent of PerfectTunes you now have a way to retroactively check all those older itunes rips for matches against the AR database. A couple of years ago (pre PerfectTunes), this would have been impossible.

[mathmat]

Re: AccurateRip question

Thank you garym and Spoon. I feel much better now regarding my rips and understand the difference between CUeTools and PerfectTUNES better. I don't think I'll be using CUETools to check the rest of my iTunes Library and just go with PerfectTUNES from now on. It's easily one of my 3 favorite programs use now. :smile:

I've had about 1 or 2 bad tracks for every 100 I've ripped with iTunes. If those tracks aren't particularly favorite songs (which a lot are) I'm ok with the results. I never knew about other programs for ripping, so since I use an iPod I just went with iTunes. I've heard others say iTunes isn't the best ripper too.

Also just curious about the CD with the one different offset? I apologize if I am possibly being redundant, but again, I'm desperate to know the status of my rips. I think we're all audiophiles here, I'm just new at the game. :smile:

Again, thanks for all your time and replies!

[garym]

Re: AccurateRip question

Also just curious about the CD with the one different offset? I apologize if I am possibly being redundant, but again, I'm desperate to know the status of my rips. I think we're all audiophiles here, I'm just new at the game. :smile:

I really have no clue (as I don't understand the deep technical underpinnings). But if it was me and I was really, really curious. I'd take that same CD and rip it again with dbpoweramp. Then see what the AR results look like in the ripping log.

[mathmat]

Re: AccurateRip question

I unfortunately don't have ready access to the CD (storage), but as long as it's an Accurate Rip for that track, I'll be happy, regardless of what the offset is for that track. And given that it says AccurateRip Verified Confidence 66 I can assume that it's a correct rip?

Thank you again for all your very helpful replies.

[garym]

Re: AccurateRip question

I unfortunately don't have ready access to the CD (storage), but as long as it's an Accurate Rip for that track, I'll be happy, regardless of what the offset is for that track. And given that it says AccurateRip Verified Confidence 66 I can assume that it's a correct rip?

Thank you again for all your very helpful replies.

yes. This means 66 other people ripping different physical copies of that cd on different computers produced the same exact bits as your rip. The odds of that being a random match have to be in the trillions to one. there are greater odds that I actually am Robert Plant and also your real father. ;-)

[mathmat]

Re: AccurateRip question

LOL! Too funny.

Thanks again for all your help garym. I have a much better understanding of how things work. I'm sure I'll have more questions in the future. :smile:

Hopefully Spoon will chime in about that one track with the different offset. That's the only thing that's got me wondering still.

[Spoon]

Re: AccurateRip question

The offset will be a different pressing submission with AR v2 crcs, which cuetools cannot lookup.