1. Mandolin attachment. A mechanical device or curtain apparatus in a piano which, when turned on, produces a "tinny" or "rinky-tink" sound similar to that made by metal or wooden hammers hitting the strings. Sometimes made in the form of a cloth curtain with separate metal- or wood-studded hanging tabs; sometimes in the form of small wooden paddles or plungers positioned between the hammer shanks and strings. A common attachment in coin pianos and orchestrions. Nelson-Wiggen called its curtain-type device the banjo attachment. Hupfeld called it the Harfe-Illusion (See harp effect.) 2. Mandolin Effect, Mandoline. A special piano action in the treble section of a street piano (also listed in this Glossary), with hard wood hammers (or hammers covered with buckskin or very hard felt) actuated by a rotating splined shaft, which strike the strings in a reiterating manner, producing a loud realistic mandolin-like ringing sound. Also used in the Wurlitzer Mandolin Quartette. In the Hupfeld Helios, where it was called the Mandolinen-Illusion, the mandolin mechanism is mounted above the regular piano hammers, providing either piano or mandolin sound.