There were digital audio tapes made (aka DAT).
The reason digital was adopted was because it is much less sensitive to noise.
I am making up numbers to demonstrate the point. My specific number are wrong, but the concept is sound
!
For a tape, you might consider the dynamic range in audio to be from 0% to 100% (at the point where the magnetic particles are saturated). Let's say you have a drum solo and at a certain point all you have is the cymbal ringing from an earlier hit followed by a hard rim shot. On an audio tape, this means you have 30% followed by 90% at the instance of the drum strike. On the tape you have a strong charge immediately adjacent (how immediately depends on the tape speed) to a low charge and the natural result is the higher charge area will bleed over to the lower charged areas making the attack less dynamic/sudden. Then there is also the potential for bleed through from the layer of tape above or below since magnetic charges produce fields that extend beyond the particle. Then there is the resolution capability of the head (which is also influenced by wear and or contamination). All of these play to reduce the quality of playback and they are generally additive over time.
For Digital, instead of needing to differentiate between 40% and 55% the signal is encoded such that particles are either charged or not - lets say 10% vs 90% and the head only needs to distinguish between <40% and >60% to correctly identify which is which. The potential for an area with 90% to bleed down to <40% or 10% to bleed above 60% makes for a much more rigorous storage of data.
The concept of breaking down sound into digital code intuitively can seem a bit offensive and over the years there has been no shortage of nay-sayers who believe digitizing "steals the soul out of the music", but I tend to look to video as proof that digitization is fully capable of containing all of the data required to present a finished presentation which is better than out ability to perceive flaws.
That and the fact that critical military and medical systems have chosen to rely on digitized content for their needs!
