SDCL § 32-15-11: Sirens, whistles, and unnecessary loud noises as misdemeanor.

It is a Class 2 misdemeanor, except as otherwise provided in § 32-15-12, for any vehicle to be equipped with or for any person to use upon a vehicle any siren, or any compression or spark plug whistle, or any exhaust horn, or whistle which does not produce a harmonious sound, or for any person at any time to use a horn otherwise than a reasonable warning or to make any unnecessary or unreasonably loud or harsh sound by means of a horn or other warning device.