Digitization means to divide the data into finite blocks(chunks) and then assigning each block an average(or constant) value so that entire data is represented in finite set of numbers only.
This causes some loss in information when when reconstructing it back.
So you are missing some sharpness kind of feel in your recorded music.
Spectral Decompostion: A much better method for quality is by using the Fourier transform to convert the recorded data into some magical numbers called amplitudes of different frequency waves. These can be computed indefinitely to the extent of required quality of your sound(signal).
i.e. more fourier numbers gives much better sharpness in sound.
P.S: It depends on the sound sensor capability of recording frequency range too.