Acousmatic music was born from the philosophical concept of ���epoch����� that means that the existence of the world doesn���t matter and that the subject pays attention to his own world���s perceptions. The epoch�� gave the concept of reduced listening. Besides, music and sounds are invisible and acousmatic means hearing without seeing the cause of the sound. This is possible by recording sounds. All of this implies the abolition of the distinction between inner and outer. For these reasons, acousmatic music has a deep relation to invisible and particularly to invisible inside Being. This paper aims at analyzing the mechanisms implied by this invisibility and the philosophical consequences of these mechanisms, related to the onto-logic analysis of the being by Martin Heidegger, and aims at highlighting the very close connection between the acousmatic music and Being. Acousmatic music, born from phenomenology, will find a strong echo in the theories developed by Heidegger in Being and time, and can be considered as a particularly ���existential��� art.