[Ron N.]

someone wrote:
There is no analog-equivalent of sample-rate? Then what the limits the
highest frequency an analog audio device can encode?

What determines the highest frequency signal an analog solid-state
audio device can input without distortion?

The basic physics of material objects leads to some
limitations. At some frequency, a given force can
no longer accelerate the mass of a given physical
transducer or recording substance by an amount
greater than does thermal noise (and other sources
of noise, such as friction, wear, dust, magnetic
particle size, film grain size, etc.)