This thesis is comprised of a portfolio of musical compositions with accompanying media and a written commentary. In each of the seven compositions, the timbral palettes of musical instruments have been expanded through unconventional physical manipulation. The written commentary presents, in detail, specific examples of how this has been achieved. Alongside descriptions of the work in question, select aspects of other composers' music that approach a similar aesthetic are also referred to. In addition, the fundamental role technology has played in the creation or realisation of certain pieces is addressed. Also included are descriptions of the various customised notational systems used throughout the portfolio. It is outlined how each of these systems has been constructed in a clear and practical manner and, where possible, has incorporated elements derived from the lingua franca in order to communicate the required information as efficiently as possible to the performers.