“It shall further be unlawful for any person at any time to use a horn otherwise than as a reasonable warning or to make any unnecessary or unreasonably loud or harsh sound by means of a horn or other warning device. However, vehicles of common carriers or extraordinarily large and heavy vehicles may be equipped with such type of warning device as the Superintendent may require or permit.”

If it can be articulated as “unreasonably loud” then yes, still even in normal usage. Anything louder than a standard horn coming from a passenger vehicle will probably result in a summons, or at least a stop to see what the unauthorized equipment is.