True---you can buy dvd players under $100. You could never buy the parts with the extra laser needed and other circuitry for that.
It is like buying a new car from a dealer. If you tried to build the same exact car from new parts it would cost you 5 to 10 times more.
i thought about doing this to, i can't see why you couldnt just buy a 30.00 dvd player and merge the two together....maybe i am being to simplistic about this. all a cd jukebox is is a cd player with a turntable so why not swap out the parts?
The electronics is beyond most people - better to buy new - Toshiba SD-3950 is $60 and they sound surprisingly good too as a CD player!
Here i think the question is, can you swap the laser of CD Player so it could play the DVD?? I think that is great idea, but it is challenging, I heard people done it. but not quite sure what got changed. I am pretty sure the could be done so you could your 10 cd placer with 10 DVD disc. Good luck. I will search too for it.
I'm no expert in Home Audio or HT (you can see by my threads in receivers...) but do know enough about electronics to know this really isn't that simple. Sure, if you can find a laser with the proper packaging form factor to swap into the CD player you'll have the right laser to read the DVD. BUT, there is all the decoding electronics behind the laser to interpret the signal it generates. Don't forget the necessary connections for the video & multi-channel audio lacking in the CD player.