This paper re-examines several topics in Greek musical theory at the beginning of our era, as are enounced and dealt by Sextus Empiricus in book VI of his Adeversus mathematicos: sound, notes, melodic genera and ethnos. In his definition it is possible to trace his times' musical theory as well to study its dealing by this author. [Sexto Empírico y la ΜΟΥΣΙΚΗ, p. 95]