Check out this link
Home Page
And click on the 7 links under Digital Playback heading on the lower lfet corner of the page.
A lot to read but this may give you some appreciation for a few of the issues involved in how a CD player works.
I think there is a misconception about CD play back. Much more of the process of reading information off of a disc and converting it into an analog waveform is analog (rather than digital) than you may think.