Re: [gentoo-user] Verification of audio CD copy?

[Dale]

Mark Knecht wrote:
> On Tue, Jun 2, 2009 at 7:42 PM, Paul Hartman
> <paul.hartman+gentoo@×××××.com> wrote:
>
>> On Tue, Jun 2, 2009 at 8:03 PM, Mark Knecht <markknecht@×××××.com> wrote:
>>
>>> Hi,
>>>   I've got a bit of a problem recently with (I think) k3b. Over the
>>> last couple of months *some* copies of CDs made in k3b using the Clone
>>> Copy feature do not reliably play in my car's CD player. I've tried
>>> multiple CD spindles and I've tried burning the copies on two
>>> different Gentoo machines - one 32-bit and the other 64-bit - with the
>>> same results. The thing that is VERY strange about this problem is
>>> that some CDs and all copies of those CDs play fine. For other CDs the
>>> originals play fine but every copy I make fails, and if they fail,
>>> they fail using either Gentoo machine to copy them. (Hope that's
>>> clear....)
>>>
>>>   I'm wondering if there is a program that can verify the contents of
>>> each CD against each other, bit for bit, to identify whether this is a
>>> problem on all of my computers or whether it's something about my
>>> car's CD. The strange thing is that the original CDs play fine in the
>>> car. It's only the copies that sometimes don't, and it's only the
>>> copies of *some* CDs, not all CDs.
>>>
>>>   I've been using these same machine and same car CD player for years
>>> and everything has always been fine. Now for the last 2-3 months
>>> nearly 50% of what I copy fails.
>>>
>> I don't think there's a way to do bit-for-bit compare of audio CDs...
>> if it's a burning issue I would try burning at a slower speed (as slow
>> as you can tolerate waiting for).
>>
>> Maybe your car's CD player/laser is dying. Perhaps try taking some old
>> CDs that you know used to work and see if they still play okay. The CD
>> player in my car for the past month or so has decided to be unable to
>> play a CD without skipping like crazy. It is maddening.
>>
>>
>>
> Reading around on the web I got pretty much the same picture - that
> it's not possible to verify 100% bit-for-bit that an audio CD is
> identical. Still, I would think that if I made whatever the 'iso' is
> of a single CD twice and compared the two of those I'd expect them to
> be the same, but maybe we cannot really guarantee the burning
> operation is exactly bit-for-bit. I don't know.
>
> It likely is the car's CD player but it's been hard to prove so far.
> It plays all originals fine. It plays most copies fine. However it
> fails on all copies of certain CD lately no matter what Gentoo machine
> I burn them on. Strangeness.
>
> Thanks for answering back!
>
> - Mark
>
>
>

Could it be some copy protection thing that is new maybe?  Something k3b
can't quite copy.

Dale

:-)  :-)