Music transmits information in various ways, thus this noble form of art can be seen as a communication system. In analogy to telecommunications, a basic path transmitter-channel-receiver can be redefined in terms of musician-medium-listener, where the musician category should be intended as the sequence of composer-performer. In this perspective, it is interesting to study how complex messages conceived and produced by a musician can been conveyed through a performance or a medium. A music composition is a multidimensional entity where the emotional states play a major role. How efficiently can be these elements transmitted and why? Which conscious or unconscious phenomena occur in the music communication chain? These are some kind of questions that this discipline tries to answer to.