hi there,

I wonder if one can trust EAC's quality report after ripping a CD. I've ripped a CD and there was one song where EAC had to do some error-correction. Therefore, the quality report said 99,9% (instead of 100% like the other tracks on this CD).

I tried it a second time, this time with my DVD drive (and not with my CD burner), the result was a different CRC but still the same problem. The CD doesn't have any copy protection by the way.

Anyway, I purchased the same CD again - brand new - but EAC still had to do error correction on this particular track and therefore I got the same quality level: 99,9%. Again I tried it using my DVD drive without any better results...

So how can that be? All other tracks on this CD did fine...I just found it suspicious that this error occured on both CD's, same track...even though one CD was brand new...

May of been made from bad masters.

99,x% of total quality is very common with EAC. It often occurs when EAC performs some correction at the end of the track. It doesn't mean that glitches were introduced within the track. Try, if you want, a SECURE + TEST & COPY extraction. You'll probably obtain the same quality level (99,9%) on oth extraction and the same CRC checksum.

Did you set up the correct read offset corrections?

IIRC, I believe the 99% quality is because of sample rounding.

what do you mean by that? As I said, all other tracks got a 100% quality level. Some tracks already clipped at 88dB, but still got 100%...


that's what happened...


so how would I do that? There is only an option called test & copy...when I first started EAC I said the I want to have the most secure results and don't care for speed...


I've no idea...EAC did all the settings for me...it even had my DVD + CD burner in it's database...


hmm...

Then, you're already in Secure Mode.
Now, select your track, and type SHIFT F6. At the end of the extraction, look on CRC checksum for both extraction (the TEST one and the COPY one). If both values are identical, your rip should be fine (e.g. without errors [yes, I know, it's not that simple, same error could happen twice...]).

I've done that before and the CRC was always the same (even for both CD's)...so I guess there was no problem with the CD in first place

http://www.hydrogenaudio.org/forums/index....hl=99%+with+eac

As far as I know: (track quality) = ((number of sectors to be read)-(number of sectors actually read more than one times (ideally 0)))/(numbers of sectors to be read) * 100%
(or the like)
Track quality has nothing to do with mastering, sample offset and the peak level/clipping/compression. Personally I believe the occurance of less than 100% under perfect conditions is still a bug in EAC that has not yet been removed.

I subscribe, what precisionist wrote.
Though, I don't think, that values below 100% are an EAC-bug. EAC behaves quite deterministically, a value below 100% just tells, that EAC performed re-reads on a track.
btw., at very long tracks and only very few rereads (like copying an CD-image), you might get 100.0%, but EAC DID (few) Rereads. Why 100.0% ? Because of rounding the percentage from let's say 99.97 to 100%.
Why EAC does rereads, well long chapters are already written about.
For the thread-starter or generally starters on secure audio archiving, extracting, I recommend http://www.High-Quality.ch.vu

Just out of curiosity...
When you ripped the two CDs using your CD burner, did you get the same CRCs?
When you ripped the two CDs using your DVD drive, did you again get the same CRCs?

that's two times a 'positive'

All four CRCs should be identical...

nope, that wasn't the case...

CRC is only an 'abbreviation' for the extracted audio data. It will be different if the audio data is different and vice versa. That means that there's something wrong. Rips of the same track/CD from different drives must match.

Excuse me, but why "Shift" + "F6".
What's the difference from using only "F6"?

It is just that I always use F6. Now I am away from my ripping computer and I can't check this out myself, but I felt a cold shiver at the thought that I might be doing something wrong...

If this is the case for a track in the middle of the CD, then one of the drives at least is not configured with the right offset. The case of a permanent isolated error may have been considered with a CDR burned in TAO.

If it is the first or the last one and the offsets are ok and there is no permanent isolated error (very rare outside TAO CDRs, about 1 Cd out of 1000 ), then one drive at least can't overread.

From http://www.High-Quality.ch.vu: Offset and Gap Detection optional ?

][/quote] From http://www.High-Quality.ch.vu: Offset and Gap Detection optional ?
[/quote]

yes, offsets are normally not influencing listenable the sound quality perceived.

and sometimes very difficult to get for starters.
but the how to is of course explained in that guide.

I have an old Mitsumi drive. It produces permant errors during EAC-ripping: Near the end of every track is a small click. Except this click, the rips are sample-identical to the true rips verified by the other drives. The strange thing is that EAC doesn't notice this error, even the CRCs are identical: The error happens always in the same way...

ps: cool quote cascade

Yes, I didn't mention the case of bugged drives. It also happens with some Samsung (silence at the end of every track) and one Toshiba (isolated error in the middle of every rip, always at the same absolut time) drives.