[X4U] CD : Digital Audio cd same as CD for data?

[David Ledger]

>From: Frank Isackson <fisackson at earthlink.net>
>Subject: Re: [X4U] CD : Digital Audio cd same as CD for data?
>To: "A place to discuss Mac OS X for the casual user."
>	<x4u at listserver.themacintoshguy.com>
>Message-ID: <954A0C2F-D501-4007-BE29-34E1230941A3 at earthlink.net>
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>
>The quality standards for data media are higher than those for music.
>If a microsecond of music were missing your ear wouldn't notice; a
>microsecond of data could a catastrophic loss. Similar logic is at
>work in the hard disks in iPODs. They are not as fault-free in
>recording music as their brethren produced for data storage.

Disc segment data includes full CRC data checking, so unless they 
designed and manufactured special non-standard controller cards to 
build into the drive, that isn't the case. They may have a larger 
number of bad blocks, but bad block relocation has been normal since 
not all that long after disc drives were invented. Bad blocks don't 
cause incorrect data. A block going bad on you can cause data loss. 
Like most digital things, it's there, perfect, or it's not there at 
all. CD-Rs, being rather wooly at the pit level, can be an exception.

David

-- 
David Ledger - Freelance Unix Sysadmin in the UK.
Chair of HPUX SysAdmin SIG of hpUG technical user group (www.hpug.org.uk)
david.ledger at ivdcs.co.uk
www.ivdcs.co.uk