A method and corresponding system for generating harmonics from an input signal having an input frequency uses a harmonics generator having an associated gain controller generating adjustable gain control factors, controlling the amplitude of harmonic components. The method includes generating a series of harmonic components in a process including adjustment of relative balances between at least three harmonic components of different orders, the balances being independently adjustable by controlling at least two gain control factors. Each gain control factor is adjusted based on a frequency dependent measure of the input signal or signal derived therefrom, of the frequency dependent measure of the input signal and/or derived signal unique for the corresponding gain control factor. An output signal is created including the harmonic components according to the balances as controlled by the at least two gain control factors, wherein the balances between the harmonic components depend on the input frequency.