During the 1980s and 1990s, English electroacoustic music composer Jonty Harrison (1952-) composed a series of tape pieces and collected them in an album called ´Evidence mat´erielle in 2000. In this thesis, two pieces, Klang (1982) and Surface Tension (1996) have been analyzed in order to place them accurately within the contextual framework drawn by Pierre Schaeffer, R. Murray Schafer, and Simon Emmerson. To discover the relationship of those concepts to Harrison’s music, the author investigated Pierre Schaeffer’s Treatise on Musical Objects (1966 edition), R. Murray Schafer’s The Soundscape: Our Sonic Environment and the Tuning of the World (1977 edition) and Simon Emmerson’s The Language of Electroacoustic Music (1986 edition). The intention of this work is to explore the musical connections between syntactic and semantic usage of the sound source on Jonty Harrison’s Klang and Surface Tension regarding the musical approaches of Pierre Schaeffer and R. Murray Schafer.