The famous Abbey Road Challen Piano It is known as a piano of two distinctive sounds: its original, warm and mellow tone, and its contrasting bright tack sound, for which it owes its namesake. The piano has brass-tipped strips of felt that can be dropped between the hammers and the strings to create a hard, percussive note. Because of this feature, achieved by operating the centre piano pedal, it became commonly known among Abbey Road studio engineers and visiting artists as the ‘Jangle’ or ‘Jangle Box’ piano.