Here is a thought experiment.

Consider a thin superconducting circular loop of wire. Suppose there is a supercurrent flowing through the loop. Let $v$ be the tangential drift velocity of the electrons and $r$ the radius of the loop.

Now suppose you place an observer at the center of the loop and they begin to rotate with angular velocity $\frac{v}{r}$. Then from their perspective the electrons are static. Now suppose you somehow "pushed" a set of electrons in the wire a little ahead, that would creative effectively an electrical pressure that should appear to propagate around the loop like a sound wave (from the rotating observer's point of view), (and could potentially be quantized).

Where can I learn more about this type of "electrical sound"?