Lets first listen to what CDs, DVDs, and Blu-ray discs sound like as you flap them from the central hole and drop them onto a counter. Binaural recording. 

now will put each different kind of media into a CD burner without the computer on just to hear the laser and reading sounds. iPhone laying on top of the burner to catch some contact. 

finally, let’s burn a Blu-ray disc. 40 GB onto a double layer Blu-ray that can hold about 47, quoted at 50 GB. Burned disc at 6X. Again the phone is laying on top of the drive.