1. A system for controlling the quality of an industrial process, comprising: a sensor for measuring one or more process parameters, and an electronic control and processing unit for processing the signals emitted by said sensor, wherein: said electronic control and processing unit processes the signals emitted by said sensor by performing the following steps: having one or more reference signals relating to the industrial process, acquiring one or more real signals which are indicative of the quality of said industrial process, obtaining a transformed signal from said reference signal, obtaining a transformed signal from said real signal, calculating energies of said transformed reference and real signals, comparing said one or more reference signals to said one or more real signals to identify defects in said industrial process, wherein said comparing step comprises: comparing said energies of said transformed reference and real signals to each other to extract corresponding time frequency distributions for selected frequency values; calculating energies of said time frequency distributions; comparing the energies of said time frequency distributions with threshold values to identify energy values associated to defects; and providing said energy values associated with the defects to a classifier, wherein the method further comprises providing said classifier with the energy of said real transformed signal.