Singing suppressor device

Claim 1

A singing suppressor device (5) for preventing singing and self-oscillation that arises owing to acoustic feedback in an electroacoustic chain (2 to 7) that includes at least one source (1) of audio-frequency signal, at least one sound sensing device (2), at least one amplifier (3, 6) connected to the latter, and at least one sound transducer (7) fed by said amplifier for emitting the audio-frequency signal; the device comprising, in combination, at least one delay unit (51) in said electroacoustic chain between an audio-frequency input (U in ) and an audio-frequency output (U out ) of the device, said delay unit having a delay time dependent on the frequency of a signal applied to at least one electrical control input of said delay unit, that determines the delay time; at least one control generator (53) at least indirectly coupled to said control input, for generating an electrical signal that varies in time, and consisting of components of a frequency less than that of the lower limit of the transmitting band of said electroacoustic chain; the coupling between said control generator and said control input of the delay unit being through a serially connected modulator (54); and at least one auxiliary generator (52) coupled to an input of said modulator; wherein at least one of said control generator and of said auxiliary generator is in the form of a signal converter (55) that shapes and transforms the audio-frequency signal, said converter having an input coupled to said source of audio-frequency signal at said audio-frequency input; whereby the singing and the self-oscillation are successfully eliminated in said electroacoustic chain, with the absence of any distortion, dissonance and the like being introduced in the audio-frequency signal.