Ryterski composed P.E.R.C.S. in the middle of 2014, during his studies. It was his first approach to electroacoustic music. This around 25 minutes long piece is a representation of chronic disease in music - a particular disease that binds body and mind. Ryterski's main inspiration for this work was the story of Theresa Nadeau, a woman who was suffering from Systemic Scleroderma - an autoimmunological illness which makes the body destroys its connective tissue. 

 

P.E.R.C.S. is divided into 5 movements: muscles and esophagus, joints and bones, skin, lungs and heart, mind (originally animus). Each one of these represents different idea and pacing of music events - while the odd numbered movements are rather fast or intensive, the even numbered are the opposite. During the piece, percussionist not only has to play his part on the instruments, but also has to move properly - there are 2 movement sensors attached to their forearm. By using different parameters of the movements, the Max/MSP patch evokes or alters the sounds that are coming from the computer.

 

The piece was performed by 2 percussionists: Radosław Mysłek (2014-2015) and Tamara Kurkiewicz (2019).