Mauricio Kagel's "Heterophonie / Improvisation ajoutée" is a captivating journey into the avant-garde, released on January 1, 2001, under the label Wergo. This album is a testament to Kagel's innovative approach to composition, where he sets the stage for spontaneous creation within defined structures. The five-part "Heterophonie" series invites musicians to explore and reinterpret the score, resulting in a unique sound experience each time it's performed. The album also features "Improvisation ajoutée," a piece that delves into the intricate world of piano and percussion, particularly focusing on the often-overlooked interior of the piano. With a duration of 49 minutes, this album offers a rich and immersive listening experience, showcasing Kagel's ability to blend improvisation and composition in a way that pushes the boundaries of traditional music.