the difference between a digital and an analog recording. 

Natural sound is by definition analog.
When a CD recording is created, this analog is sound is digitized. To
do this, they take a lot of snapshots of the analog sound. For a CD
recording they take 44,100 snapshots in a minute. These snapshots are
then converted to digital information with a certain precision. For a
CD recording this precision is 16 bits which means that every one of
the 44,100 snapshots needs to be converted into one of the 65,536
(2^16) possible values.

You can probably see where I am going: by definition a digital
recording doesn't include all the sound information. You could
visualize a CD recording as a really large chest with a lot of
drawers. Because the number of snapshots that are taken are not
infinite (the maximum is 44,100 per minute), the process of taking
snapshots results in the loss of information. Information is further
lost because each of these snapshots must be made to fit in one of the
65,536 drawers of the chest.

A record player which plays LP's is strictly analog. A vinyl record
has a groove carved into it that mirrors the original sound's
waveform. The record player than transforms this groove to an analogue
sound signal which can be fed into an amplifier.
In this process, no information can be lost. No snapshots need to be
taken and the sound doesn't need be converted to one of the possible
65,536 values. There basically is an infinite number of 'snapshots'
and 'possible values'. Therefore vinyl recording sound richer than CD
recordings (as long as you have a decent vinyl record player).

Be aware that recent DVD Audio players and Super Audio CD players come
closer to vinyl recordings as they have a much larger number of
possible snapshots in one minute (up to 192,000) and because these
snapshots can be converted to a larger number of possible values (up
to 16,777,216 possible values, or 24 bit). "

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