Radar-based counter-battery fire already exists and would be far more accurate, as radar tends to propagate more predictably (and faster) than sound.

Though yes, that's an option, it's called artillery sound ranging:

<https://en.wikipedia.org/wiki/Artillery_sound_ranging>

A subset of acoustic location: <https://en.wikipedia.org/wiki/Acoustic_location>

Audio-based range-finders were used extensively in WWII:

<https://yewtu.be/watch?v=04F5osXK4vw> (Tom Scott: "Testing the sound mirrors that protected Britain")

Also: <https://www.gettyimages.com/detail/news-photo/german-world-w...>

Optical rangefinders were also used: <https://www.navalgazing.net/Rangefinding>

(I've tried but failed to find large audio/sound based naval rangefinders, which essentially consisted of gigantic ear trumpets, roughly the size of a human. Used in WWII by both US and Japanese navies as I recall.)

Acoustics would also struggle to determine friend from foe, if tanks or arty, and then you'd have to deal with dissipation and echoes and other weird effects. with a radar you actually can spot the the shell trajectory and turn that into a parabolic arc. then make some rough guesses as to how far they've traveled since then ("shoot and scoot"), and you can map out a firing solution that covers most of a given area.

MLRS/rocket arty is great for that since it can fire off a lot of ordinance quickly, at the cost of long reload times. saturate the grid square before their artillery can get away.

Radars get you into the EW cat-and-mouse game, tho.