Without a doubt the most powerful instrument in musical therapy, is the own voice of the man. The song and the work with the overtones are one of the recommended and effective exercises of musicoterapia more in sessions for example of musical composition. The overtones, are frequencies we would say secondary to an original sound that are added in a whole. A voice difference of another one by its overtones. For example if a singer of operates gives a note and another singer gives the same exact note, always they would sound different the voices and this is by the overtones. The practical work with the vocal overtones and frequencies gives result to very positive therapeutic sessions of musicoterapia since several important capacities of attention are developed, discernment, East etc. work with the overtones and with the song it would be included as much in the active musicoterapia in recreation, composition and musical improvisation.