Acoustic devices on Italian Horizon-class destroyers

What are the acoustic devices on Italian Horizon-class destroyers used for?

They generate loud sound for lower-level threats; using them to incapacitate a merchant crew in wartime is a speculative, close-range possibility.

The acoustic devices described on the Italian Horizon-class destroyers generate loud sound for encounters below the level of full combat. A suggested wartime use is to incapacitate a merchant ship's crew with noise during a capture. That application is speculative and would require very close range.