-> > The CD rotates at roughly 500 rpm at the start as it is read from
-> > centre to outside edge.  At the outer diameters, the speed is 200
-> > rpm.  This is done to ensure the data that comes off the disc is at
-> > the proper rate.
So the CD player rotates the CD at different speeds as it reads
the disc from inside to outside?  You'd think that it would be difficult
to set each CD player to such exact specs, but it does make sense that
the speed would have to change, otherwise your data would be coming off
the disc at variable rates.  John has a good point here.  I thought that
the CD player spun the disc at a constant rate, like a record player.
Though now you have me confused.  A record player rotates at a constant
rate, yet even though the inside edges and the outside edges travel at
different speeds, their is no difference in pitch between the outside
and inside edges.  (Meaning if you had a 33 record playing at 45rpm,
it'd be higher pitched, yet even though the edges are traveling at
different speeds, it's the same pitch throughout the record).  Seeing
how it's summer, my brain isn't working the way it should, so can you
please explain this?
JA> I am far, far, far from being knowledgable about ANYTHING
JA> digital, but in thinking your reply through, it would seem that
JA> the rotation speed is the same for the inside edge of the CD as it
JA> is for the outside edge. When point A of the disk interior edge
JA> passes a stationary point off the disk 500 times in a minute, so
JA> would point B on the exterior edge.  My laymans logic would think
JA> the difference is the amount of digital data read from the inside
JA> track versus the outside track would be very different, with the
JA> exterior providing more data than the interior, provided it was
JA> given data at the same density (wrong term?).
JA>      Where am I missing the boat?
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