What is an acoustic decaphonic piano?

The hero of this lecture, the decaphonic piano, is an acoustic concert hall instrument created on the demand of the world-famous jazz pianist Leszek Możdżer. The piano is decaphonic since it needs ten sounds only to play the entire octave, in contrast to the twelve sounds played in an octave by the usual piano. Musical tuning system of this piano is the ten-scale well temperament, as opposed to the 12-scale well temperament used by musicians in most of the Western music since the times of J. S. Bach.

The acoustic decaphonic piano was created by four people: Aleksander Bogucki, a physicist from the Institute of Experimental Physics of the University of Warsaw, Paweł Nurowski, a mathematician from the Center for Theoretical Physics of the Polish Academy of Sciences, Andrzej Włodarczyk, a constructor and a restorer of ancient pianos, and by Leszek Możdżer - the initiator of the project. As far as we know it is the first such musical piano instrument in the world.

In this lecture I, as one of the two scientific designers of the piano, will explain technical difficulties, scientific obstacles and esthetic prejudices, which we had to overcome to create an actual physical implementation of the instrument.

People without a musical education are most welcome to the lecture. All the relevant scientific information to understand the innovative nature of the instrument, and motivations for creating it, will be explained. In particular, I will explain the mathematics principles of various musical tuning systems used in the history of Western music, so that after the lecture everybody will know what is the Pythagorian tuning, just intonation, well temperament and how the tuning system of our instrument is related to these classical notions. I will try to argue that mathematics prefers the tuning system employed in the decaphonic piano. The sounds of these various tuning systems will be presented and compared with each other during the lecture.

A physical implementation of the decaphonic piano, and the actual music played by the instrument, was presented on the concert of Leszek Możdżer during the  World Premiere of the Acoustic Decaphonic Piano, which took place at the Concert Hall Nowa Miodowa in Warsaw, Poland, on 13th of July 2023. The concert was an accompanying event of the mathematics conference 'GRIEG meets Chopin', which gathered together about 100 mathematicians and theoretical physicists from the World.

The entire Decaphonic Piano Project was financed from the grant SCREAM (Symmetry, Curvature Reductions, EquivAlence Methods), sponsored by the Polish National Science Center via the Norwegian Financial Mechanism 2014-2021 of the European Union.

‍

This is an onsite event:Auditorium of the Institute of Physics PAS, Al. Lotników 32/46

‍