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Optical Drive Error Correction Ability On Read


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[ This may seem like it's about circumventing copy protection, but it's really not, honest yer honour - it's about error correction, okay ? ]
Warning - long'ish; I'm mainly just sharing what I've learned for other readers' benefit, but I do have a tiny question at the end.
So ... here's a surprising thing: some months ago I recall having difficulty playing a music CD (Tom Waits as it happens, shop-bought) on my usual workstation, using its optical drive.  Specifically, both real-time playback, and ripped tracks exhibited "noise" that sounded like fluff on the needle (showing my age here I know) - but this is a nice, clean, well-kept CD, so it can't be.
Remembering I had successfully played the same CD long ago on an older workstation, I fired the older workstation up again, and found the Tom Waits CD still played fine there.  Figuring there must be some subtle difference in laser beam calibration or some such, I thought no more about it.
Until yesterday, when I needed to use the installation CD for a very old version of Adaptec (now Roxio, no wait .. Corel this week) Easy CD Creator - specifically V4.0.2, dated around 2001.  Don't ask ... okay, because the bundled Jewel Case Creator (cover printer) is rather wonderful, if you must know.
But now I ran into a vaguely analagous problem - the EZCD installation CD (a proper disc acquired with an old Freecom CDRW drive) wouldn't read on the new workstation (some but not all files failed to copy, reporting I/O failures of various kinds), so I tried it on the older workstation, and again the older optical drive had no problem at all copying all the installation files onto the hard drive (thence across my LAN to where I needed them).  So now my curiosity was fully engaged and I began to google.
It seems that some optical drives incorporate "error correction capability" of an altogether higher grade than others, and in particular the phenomenon I've noticed may be explained by my old workstation having an ASUS E616P2S DVD-ROM drive, while the new workstation sports a seemingly spiffy Samsung "Super Writemaster" SH-222BB burner.  Apparently, some audio CDs incorporate a form of copy protection that works by including deliberate data errors on the CD, that a standard domestic CD audio player will correct using interpolation, while many PC CD drives allegedly choke on the errors and cough out garbage.  This may be the root cause of my music playback problem.
I'm horrified that music corporations would do that (okay - I *do* know about Sony), and that while my ancient Marantz CD-48 domestic hifi CD player can handle such CDs, a much newer and otherwise high quality computer optical drive is incapable of the same thing.  Also, I tend to agree with comments "out there" to the effect that it is irksome that the audio quality of the music on such CDs is deliberately degraded (even in a domestic hifi) from what it could be, for the benefit of the damn accountants.


All this assumes the form of copy protection I've encountered is indeed implemented by adding spurious but real data errors. Seems likely - but I suppose it could be something else - there's apparently something called 'Audiolok' which works by adding completely fake unnecessary "error flags" to the CD which a domestic player is too stupid to notice but which the high-quality error-detection electronics in a PC optical drive detects and gets confused by.  In which case I'm being entirely unfair to Samsung, and what I'd need is a stupid drive, rather than a clever one - well for music anyway.  I would need a stupid one for music, and a clever one for old data discs.  Sigh.  What a load of unnecessary angst caused by greedy record industry companies.


But irrespective of the music problem, I like error correction capability very much (I'll build a PC with ECC RAM when I can afford it), and would like to buy only drives that are good at it from now on.

Up to now I'd been very impressed by the Samsung drive (it's fast, quiet and burns well), but now it feels like the scales are falling from my eyes.   I've feverishly tried playing a large number of other shop-bought music CDs on both workstations, and have found quite a few that give the same "fluff-on-the-needle" problem when read by the Samsung drive, but not when read by the ASUS drive.
I've found posts asserting that the ASUS drive has very good error correction, but others comparing ASUS drives unfavourably with e.g. LG drive capability.  While I've found no comments about the Samsung burner (but see club.myce below), I infer from my experience that it has lousy error correction.  NB: some folks suggest the ASUS drive is actually a rebadged Pioneer drive.
So my queries:

  1. Is this something that old hands have known for ages ?  
  2. If so, and if there's a FAQ somewhere about relevant optical drive hardware capabilities that I should read, please cluebat me.  
  3. Most usefully: is there a brand of optical drive (burner or simple reader) that is recognised as being best at error correction ?

PS: I've already seen this :
which has:

  • Q: Is the Samsung a reliable CD scanner?
  • A: Not at all. The drive does not report back all C2 errors to the application (CD/DVD Speed or Kprobe), also the reported C1 errors are way too low to believe them. So just forget it. Or the other way: If there are C2 errors, then the disc is really bad.

which kind of affirms the idea that Samsung drives are crap at error correction.


PPS: before you kids start mocking  :goatee:, yes I know nobody in their right mind even buys optical disc music any more, it's all about digital downloads and streaming whatchamacallits these days.  But I have a large collection of bought'n'paid-for CDs, and I reserve my right to be annoyed by disc-based DRM, ok ?  Now git orf my lawn :wink:

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