Let-off, also known as escapement, is the mechanism of the hammer releasing from the jack and lower action when the key is struck. It is a critical part of the action mechanism, and very influential in the touch and feel of the piano. It is sometimes called ‘set-off’ in the UK. Function: Let-off is designed […]

A jack is the L shaped component that is found in piano actions, and the whip assembly in Wurlitzer pianos. In Wurlitzer pianos, it is commonly known as the fly – but the two terms are interchangable. Function: The jack plays a crucial roll in let-off, a major part of the action process when the […]

A bridle strap or bridle tape is an action part found in upright acoustic pianos and Rhodes pianos. It consists of a fabric strap that has a leather end with a punching in the centre. Its function is to aid in movement of other action parts. Upright Pianos: On upright pianos, one end of the […]

Lost motion refers to the amount of movement that is not transferred between different parts of the piano action when it is engaged. It is usually because a small gap is present between different components. Because the energy is not transferred, it is referred to as ‘lost’. Function: This space is designed between mechanisms to […]