The invention is related to sound processing methods, especially to digital sound processing methods. In an embodiment of the invention, the method includes at least the following steps: calculating the magnitude spectrum of a segment of the sound signal, processing of the calculated magnitude spectrum to produce an outline of the spectrum indicating the peaks of the calculated magnitude spectrum, processing said outline to adjust said peaks and surrounding frequency areas of the spectrum, applying a Hilbert transform to said processed outline for forming the complex spectrum of a minimum phase impulse response, and convolving said minimum phase impulse response with said segment of the sound signal for forming a processed output signal segment.