Diaphone

A diaphone is a type of musical instrument, specifically a kind of brass instrument that employs a double reed to produce sound. Traditionally, the term "diaphone" is more commonly associated with a type of mechanical device known as a diaphone foghorn, which is used in maritime settings to signal ships in foggy conditions. The diaphone foghorn generates sound by forcing air through a pair of reeds that vibrate to produce a distinctive, low-frequency tone.