Help understanding log

[mathmat]

In my quest to understand how AccurateRip works, I came across something I don't understand that I'm sure has a simple answer.

From what I have read on the message boards, it seems AccurateRip stores different CRC values for different offsets of the same CD. That's for both ARv1 and ARv2. Is that correct?

Anyway, I ripped a CD (The Wall) on another computer a few years back. I then ripped a different physical disc of the Wall (same CD, different pressing) on my current computer recently. (All with iTunes because I use an ipod for all my listening.) In addition, but I'm not 100% sure, I believe my old drive had a read offset of +102 and my new one has a read offfset of +48.

Here are the logs:

Pink Floyd - The Wall (AL) [AccurateRip DiscIDs: 013-0014922E-00CD2E64-8F09DC0D]
Track 1: AccurateRip Verified Confidence 150, Pressing Offset -202 [ARv2 CRC E112232E] C:\Users\A\Desktop\Lossless CD Rips\pf alac\The Wall (AL)\The Wall (AL) CD2\2-01 Hey You.m4a
Track 2: AccurateRip Verified Confidence 151, Pressing Offset -202 [ARv2 CRC BE742500] C:\Users\A\Desktop\Lossless CD Rips\pf alac\The Wall (AL)\The Wall (AL) CD2\2-02 Is There Anybody Out There_.m4a
Track 3: AccurateRip Verified Confidence 152, Pressing Offset -202 [ARv2 CRC 494EAF06] C:\Users\A\Desktop\Lossless CD Rips\pf alac\The Wall (AL)\The Wall (AL) CD2\2-03 Nobody Home.m4a
Track 4: AccurateRip Verified Confidence 152, Pressing Offset -202 [ARv2 CRC 42FC5F4A] C:\Users\A\Desktop\Lossless CD Rips\pf alac\The Wall (AL)\The Wall (AL) CD2\2-04 Vera.m4a
Track 5: AccurateRip Verified Confidence 152, Pressing Offset -202 [ARv2 CRC 94E7C235] C:\Users\A\Desktop\Lossless CD Rips\pf alac\The Wall (AL)\The Wall (AL) CD2\2-05 Bring The Boys Back Home.m4a
Track 6: AccurateRip Verified Confidence 153, Pressing Offset -202 [ARv2 CRC EB624BEE] C:\Users\A\Desktop\Lossless CD Rips\pf alac\The Wall (AL)\The Wall (AL) CD2\2-06 Comfortably Numb.m4a
Track 7: AccurateRip Verified Confidence 152, Pressing Offset -202 [ARv2 CRC 07230162] C:\Users\A\Desktop\Lossless CD Rips\pf alac\The Wall (AL)\The Wall (AL) CD2\2-07 The Show Must Go On.m4a
Track 8: AccurateRip Verified Confidence 151, Pressing Offset -202 [ARv2 CRC F7EBBE3E] C:\Users\A\Desktop\Lossless CD Rips\pf alac\The Wall (AL)\The Wall (AL) CD2\2-08 In The Flesh.m4a
Track 9: AccurateRip Verified Confidence 151, Pressing Offset -202 [ARv2 CRC 5AAD6FD0] C:\Users\A\Desktop\Lossless CD Rips\pf alac\The Wall (AL)\The Wall (AL) CD2\2-09 Run Like Hell.m4a
Track 10: AccurateRip Verified Confidence 151, Pressing Offset -202 [ARv2 CRC 92CA0091] C:\Users\A\Desktop\Lossless CD Rips\pf alac\The Wall (AL)\The Wall (AL) CD2\2-10 Waiting For The Worms.m4a
Track 11: AccurateRip Verified Confidence 153, Pressing Offset -202 [ARv2 CRC 8B1115CF] C:\Users\A\Desktop\Lossless CD Rips\pf alac\The Wall (AL)\The Wall (AL) CD2\2-11 Stop.m4a
Track 12: AccurateRip Verified Confidence 150, Pressing Offset -202 [ARv2 CRC 259BA23C] C:\Users\A\Desktop\Lossless CD Rips\pf alac\The Wall (AL)\The Wall (AL) CD2\2-12 The Trial.m4a
Track 13: AccurateRip Verified Confidence 148, Pressing Offset -202 [ARv2 CRC 6AF0E2D9] C:\Users\A\Desktop\Lossless CD Rips\pf alac\The Wall (AL)\The Wall (AL) CD2\2-13 Outside The Wall.m4a


Pink Floyd - The Wall (CD2-AL) [CDP 7243 8 31245 2 7 (CDP 7243 8 31243 2 9)] [AccurateRip DiscIDs: 013-0014922E-00CD2E64-8F09DC0D]
Track 1: AccurateRip Verified Confidence 150, Pressing Offset +48 [ARv2 CRC E112232E] C:\Users\A\Desktop\Pink Floyd - The Wall (AL)\The Wall (CD2-AL) [CDP 7243 8 31245 2 7\2-01 Hey You.m4a
Track 2: AccurateRip Verified Confidence 151, Pressing Offset +48 [ARv2 CRC BE742500] C:\Users\A\Desktop\Pink Floyd - The Wall (AL)\The Wall (CD2-AL) [CDP 7243 8 31245 2 7\2-02 Is There Anybody Out There_.m4a
Track 3: AccurateRip Verified Confidence 152, Pressing Offset +48 [ARv2 CRC 494EAF06] C:\Users\A\Desktop\Pink Floyd - The Wall (AL)\The Wall (CD2-AL) [CDP 7243 8 31245 2 7\2-03 Nobody Home.m4a
Track 4: AccurateRip Verified Confidence 152, Pressing Offset +48 [ARv2 CRC 42FC5F4A] C:\Users\A\Desktop\Pink Floyd - The Wall (AL)\The Wall (CD2-AL) [CDP 7243 8 31245 2 7\2-04 Vera.m4a
Track 5: AccurateRip Verified Confidence 152, Pressing Offset +48 [ARv2 CRC 94E7C235] C:\Users\A\Desktop\Pink Floyd - The Wall (AL)\The Wall (CD2-AL) [CDP 7243 8 31245 2 7\2-05 Bring The Boys Back Home.m4a
Track 6: AccurateRip Verified Confidence 153, Pressing Offset +48 [ARv2 CRC EB624BEE] C:\Users\A\Desktop\Pink Floyd - The Wall (AL)\The Wall (CD2-AL) [CDP 7243 8 31245 2 7\2-06 Comfortably Numb.m4a
Track 7: AccurateRip Verified Confidence 152, Pressing Offset +48 [ARv2 CRC 07230162] C:\Users\A\Desktop\Pink Floyd - The Wall (AL)\The Wall (CD2-AL) [CDP 7243 8 31245 2 7\2-07 The Show Must Go On.m4a
Track 8: AccurateRip Verified Confidence 151, Pressing Offset +48 [ARv2 CRC F7EBBE3E] C:\Users\A\Desktop\Pink Floyd - The Wall (AL)\The Wall (CD2-AL) [CDP 7243 8 31245 2 7\2-08 In The Flesh.m4a
Track 9: AccurateRip Verified Confidence 151, Pressing Offset +48 [ARv2 CRC 5AAD6FD0] C:\Users\A\Desktop\Pink Floyd - The Wall (AL)\The Wall (CD2-AL) [CDP 7243 8 31245 2 7\2-09 Run Like Hell.m4a
Track 10: AccurateRip Verified Confidence 151, Pressing Offset +48 [ARv2 CRC 92CA0091] C:\Users\A\Desktop\Pink Floyd - The Wall (AL)\The Wall (CD2-AL) [CDP 7243 8 31245 2 7\2-10 Waiting For The Worms.m4a
Track 11: AccurateRip Verified Confidence 153, Pressing Offset +48 [ARv2 CRC 8B1115CF] C:\Users\A\Desktop\Pink Floyd - The Wall (AL)\The Wall (CD2-AL) [CDP 7243 8 31245 2 7\2-11 Stop.m4a
Track 12: AccurateRip Verified Confidence 150, Pressing Offset +48 [ARv2 CRC 259BA23C] C:\Users\A\Desktop\Pink Floyd - The Wall (AL)\The Wall (CD2-AL) [CDP 7243 8 31245 2 7\2-12 The Trial.m4a
Track 13: AccurateRip Verified Confidence 148, Pressing Offset +48 [ARv2 CRC 6AF0E2D9] C:\Users\A\Desktop\Pink Floyd - The Wall (AL)\The Wall (CD2-AL) [CDP 7243 8 31245 2 7\2-13 Outside The Wall.m4a


As you can see the disc IDs and confidence values and CRCs are identcal for the rips. Only offsets are different. This suggests to me that the rips are being compared to different pressings. (I may be wrong about that though.)

So my question is, how is it if my rips are being compared to different pressings (with different CRCs) are the confidence values and CRCs coming back identical? I would think if they are being compared to different pressings, the confidence values and CRCs would be different.

I know I'm missing something obviously and there's something I'm wrong about. If anyone can help give an explanation of these logs I'd appreciate it.

Thanks!

[Spoon]

Re: Help understanding log

Because the drive offset places a rip closer to a pressing offset. The CRCs are the same because AccurateRip is designed that way (rip the same disc on multi different drives and the AccurateRip CRCs are the same).

[mathmat]

Re: Help understanding log

Because the drive offset places a rip closer to a pressing offset. The CRCs are the same because AccurateRip is designed that way (rip the same disc on multi different drives and the AccurateRip CRCs are the same).

Thanks for replying.

1) The only thing is the CDs were not the same physical disc. They were different pressings. Does that make a difference?

2) So the 2 rips were each being compared to different pressings?

3) If I may add, is the CRC that AccurateRip returns in the log the CRC of MY rip or the CRC of the rip I'm comparing it to?

Thanks again!

[Spoon]

Re: Help understanding log

1. No
2. Yes
3. Yours

[mathmat]

Re: Help understanding log

1. No
2. Yes
3. Yours

Thank you Spoon! I understand things much better now than just last night!

So if the CRC value is the CRC of MY rip, then is the pressing offset the offset of MY rip as well?

[Spoon]

Re: Help understanding log

Yes