A method for performing an active profiling of the sound emitted by a vehicle engine including the steps of injecting second acoustic waves (MW), which are able to combine with the first acoustic waves (EW) in a merge point in said primary propagation path and to generate third resulting acoustic waves (RW); and generating a driving signal for the diffuser by regulating the amplitude of harmonics of the driving signal (SP) as a function of reference acoustic waves and of a workpoint of the engine, calculating equalization coefficients (α1, . . . , αM) to be applied to the amplitudes of said harmonics of the driving signal (SP) via a self-tuning procedure, and comparing the reference acoustic waves (TW) with a simulation (SRW) of the resulting waves. The simulation (SRW) is obtained by applying to a simulation of the second acoustic waves a model of the secondary propagation path.