The prepared piano is an invention of the 20th century. By placing objects, such as screws, nails, pieces of rubber, plastic objects etc, between the piano strings, the accustomed sound of the piano is transformed in every respect. On the first page of works for prepared pianos, the composer issues instructions precisely what is to be placed where. Essentially, each preparation produces a different instrument, so to talk of a prepared piano, in the sense of a traditio