Hi!

I'm ripping my CD collection and have a lot of C2 errors on disks with no visible scratches or marks.

Ripping in secure mode in EAC takes about 12 hours on these disks!

Am I best off:

1. doing what I'm doing
2. turning off C2 error correction (EAC says my drive gets all 3 ticks in the test, accurate/cache/C2)
3. test and copy (whatever that is)
4. dBPoweramp (which repairs TOCs which a lot of disks seam to have errors in these days, as does AnyDVD which runs in my system tray)

?

What should I do to get FLACs for my Squeezbox? Is the slow method that I'm doing now going to give me a good quality disk or would I best off turning off C2 errors?

Thanks,
Fairy

It is my understanding that C2 errors are useful during a normal track read only. In EAC Secure mode, since each section is read twice and those values compared, C2 does little but slow you down.

Can anyone conform if my understanding is correct?

Technically, what EAC uses is the "CU" error flag which denotes uncorrectable (for audio CDs) errors. It uses this flag instead of re-reading every sector, which speeds things up: As long as no CU error is reported by the drive, EAC assumes that the data has been read correctly and does not have to read it again. "C1" & "C2" errors are correctable by the drive itself; in fact, the drive corrects all these errors without EAC even noticing it, so checking the "Use C2 error correction" does not help with correcting the errors, it just reports (uncorrectable) CU errors which can only tried to be recovered by re-reading the defect sector.
Another option: If you have access to a Plextor drive and Plextools Pro, you can use its advanced error correction function where it tries to reconstruct the data that is missing. Might work better than EAC with its time-consuming re-reads.

Thanks. I've almost completed archiving my collection so I think I'll live with the slow method for now and probably get a plextor drive next time as they seam to be quite smart at handling non-Red Book CDs.

These CDs are most likely copy protected. What drive and program to scan for C2 errors do you use?


It's a function activated by the F6 key (or Shift+F6 if you rip to a compressed format) in EAC. You should definitely try it in Burst mode and see if you get matching CRCs. Even if you don't get them, your drive may interpolate well enough so that you won't find audible glitches in your rips.

Those programs can work around the TOC tricks some copy control schemes (like Key2Audio) use, but they won't help you with other schemes (like CDS200) that screw around with the CD's error correction mechanism and make the ripping drive appear to run into a lot of C2s. For that you need a drive like Plextor, a Plextor cuts through copy control BS like a hot knife through butter.

Also Liteon has good drives for ripping copy protected discs. Although not all the older drive models are suited for that, but at least my SHW-1635S model works very well with EAC and copy protected disks.

Plextor drives are not especially better than any other drive when the CD has C2 errors because of copy protection.
I think that I even ran into a miscorrection trying to rip a CDS200 CD with the Plextor 716A. It was an isolated click. Loud, 10 seconds apart from any other musical part of the same level. Rereading the same part gave other clicks in other locations. The location where the first click occured was interpolated (the samples values were the exact mean of their neighbour's values).

There are only two explanations :
1-The original value was a real click, maliciously introduced by CDS200 prior to the introduction of errors, that were then positionned in order to mask it. The drive managed, by chance to correct it.
2-The fact that the Plextor corrects up to 4 wrong bytes in a C2 frames leaves room for miscorrections. It detects the error, but makes a mistake correcting it, and returns a wrong value. The ratio on this CD was around a dozen of clicks for 25,000 C2 errors (C2 + CU in Plextools Pro), which would mean, very roughly, around 99.9 % of properly corrected or concealed C2 errors, for around 0.1 % of miscorrected ones.

The rip of this protected CD was interesting. I also noticed some missing blocks. Ripping twice, there were on one of the two rips some interleaved parts of audio, that left the waveform offsetted by 6 samples after them. It means that one elementary block of data have been removed somewhere before the end of the CIRC decoding.
I don't know if this happens with normal CDs, or if CDS200 messed up things especially to cause this, corrupting a synchro header, for example.