Piazzolla, Castelnuovo-Tedesco, Bettinelli: the fil rouge that unites this apparently anomalous choice is to be sought, first and foremost, in the original character of the repertoire, composed purposely for two guitars, in other words conceived especially for this combination and for its ‘double’ and ‘specular’ sonic possibilities. This exploration of the sonic universe allows us to rediscover a repertoire whose leitmotiv can be found in the element of dialogue, in the capacity of the guitar to become ‘other’ than itself by reverberating in its own identity: the mirror image that reflects a vision that is identical and yet filtered by a reality, that captures the essence of the guitar duo as an extended form of the solo guitar, a vehicle of complementarity and of expression amplified in its sonic potential. But that is not all: the choice of three composers whose expressive forms differ widely from each other, in their genesis, in their syntax and realization, can nonetheless find coherence in their common search for a balance between the voices, in the crystalline clarity of the conduct of the parts and in the sonic representation of a singular unitarity, in an accomplished identity of intent.