Étude pour les unissons. Throughout the history of piano literature, many etudes have been written for all intervals, but, as far as I know, one has never been composed for unisons. The only way to obtain a unison on the piano is through extended techniques in the cordage. The possibilities are numerous: playing on the keyboard combined with pizzicato on the string, harmonics combined with pizzicato or keyboard, double pizzicato on different parts of the string (with the consequent change of timbre), pizzicato with a fingernail or fingertip, muffled sounds, etc. All these combinations are exploited in this Metaludio, endowing it with a great timbre richness. It is dedicated to pianist Manuel Escalante.