If the DAC is the same, how different do CD transports sound?

My CD 'player' is a network drive where I keep my digital music.  Will we have to start doing comparison A/B tests with different brands of hard drives?  Has anyone actually done that?

I’m a little late on this thread, but going back to OP’s original question -

I have been using a dedicated transport to drive a DAC. I got out an old(er) CDP of the tubed variety, but I drove the DAC with the digital output which bypasses the tube section (of course!). The difference was substantial which kinda surprised me as the dedicated transport gets high reviews for a, relatively, inexpensive transport. The dedicated transport (an Audiolab) had a very good but somewhat clinical sound, whereas the CDP (a Raysonic) sounded like it had tubes (but it didn’t, they were removed), a much smoother, full bodied sound. The signifies not much except it certainly displayed a clear difference.  I much prefer the old CDP for the CD I was playing, an older, laid back, jazz piano piece . I guess it pays to keep an open mind on this subject. 

Oh, FWIW, all wires were the same for both units.

sudnh

"the optical laser detector inside the transport is an analogue electronics device which is changing its output continuously as the laser light dims and brightens."

This is revolutionary theory indeed. Why is then a DAC (digital to analog converter) needed if a laser provides analog signal?

For most of the history of CD players there have been only a few transport manufacturers… but CD players and transports sounded quit different with the same transports. Companies that wanted to get the most out of sound would go through extraordinary feats to mechanically and electrically isolate the drives to perform their best. And it works.

This is why, although CDs are waning in popularity there are still a number of high quality transports out there. 

Different players/transports can sound VERY DIFFERENT on the same DAC!