When Adolphe Sax, the Belgian music instrument maker, patented his saxophone in 1846, he enriched the musical world with a new dimension of sound, which bridges the woodwinds with the brass in a unique fashion. This distinct tone quality, which at times resembles that of the string instruments and even the human voice, continues to inspire many composers to create a large repertoire of great variety. The Tetraphonics Saxophone Quartet also exhibits a multifaceted spectrum of literature. In addition to the emphasis on contemporary, original literature, in which modern play techniques find their application, the quartet plays transcriptions of the most diverse genres, whereby it attaches importance to a faithful interpretation without ignoring the particularities of the saxophone.

Through their different musical backgrounds, Steffen Hass (soprano saxophone), Elmar Frey (alto saxophone), Volker Ax (tenor saxophone) and Noah Bedrin (baritone saxophone) come together to form a well-balanced and homogeneous unity. They studied at various universities and colleges in the USA, the Netherlands and Germany. As freelance musicians, they also appear in the leading orchestras throughout Germany, such as the Gürzenich Orchester Cologne, the Orchestra of the Beethovenhalle Bonn, the Bochum Symphony, the Orchestra of the Staatstheater Darmstadt, the Freiburg Philharmonic, the symphony orchestras of several radio stations, such as Südwestfunk, Sender Freies Berlin, Radio Orchestra Cologne, the Big Band of the West German Radio, the King of Swing Orchestra and many others.

Since its founding in 1994, Tetraphonics has been premiering many compositions specifically written for this saxophone quartet, among them works by Christian Banasik, Michael Denhoff, Willy Giefer, Enjott Schneider, Stefan Thomas und Frank Zabel. Tetraphonics interprets original compositions of the 20th and 21st century, such as works by I. Xenakis, T. Keuris, Ph. Glass, etc. in addition to works of the classical quartet repertoire, such as compositions by Glazunov, Bozza, Desenclos, etc., as well as selected transcriptions from older periods and adaptions of swing, jazz and latin, such as works by Gershwin, Weill, Bernstein and Piazolla. In trying to reach the edge of the saxophone's almost unlimited possibilities, Tetraphonics has also been engaged in projects of quartet music and dance, recitations and music theater.

In 2000, the complete quartet was absorbed into the newly created Raschèr Saxophone Orchestra, a worldwide unique ensemble consisting of twelve saxophones, from the small soprano to the deep bass saxophone. In addition to numerous concerts and radio productions, Tetraphonics is also engaged in the pedagogical sector and gives Workshops and master classes in Germany and Italy.