Predictive protection arrangement for electroacoustic transducer

A protection arrangement coupled to the electric input of a transducer which converts an electric signal into an acoustic or a mechanic signal for protecting said transducer against destruction at high signal amplitudes, comprising:

• a monitor having a monitor output for providing a monitored signal corresponding with the instantaneous load of said transducer;
• an envelope detector having a detector input connected to said monitor output and a detector output for providing the peak value of said monitored signal, said envelope detector comprising a nonlinear predictive filter for anticipating the peak value of said monitored signal;
• and
• a controller having a signal input connected to the input of the said protection arrangement, a controller output connected to said electric input of said transducer and a control input connected to said detector output, said controller attenuating said electric signal supplied to said transducer if the anticipative peak value of said monitored signal exceeds a defined limit, said controller comprising:
• an attenuation element having an input connected to said signal input, an output connected to said controller output and an attenuation control input for attenuating the signal at the output of said attenuation element;
• a static nonlinear circuit having an input connected to said control input and an output for providing a signal if the signal at the input of said static nonlinear circuit exceeds a defined threshold;
• and
• an integrator having an input connected to the output of said static nonlinear system and an output connected to the said attenuation control input for realizing a time characteristic of the controller matching psychoacoustic requirements.

A protection arrangement coupled to the electric input of a transducer which converts an electric signal into an acoustic or a mechanic signal for protecting said transducer against destruction at high signal amplitudes, comprising:

• a monitor having a monitor output for providing a monitored signal corresponding with the instantaneous load of said transducer;
• an envelope detector having a detector input connected to said monitor output and a detector output for providing the peak value of said monitored signal;
• and
• a controller having a signal input connected to the input of the said protection arrangement, a controller output connected to said electric input of said transducer and a control input connected to said detector output, said controller attenuating said electric signal supplied to said transducer if the anticipative peak value of said monitored signal exceeds a defined limit, said controller comprising:
• a delay element having an input connected to said signal input and a delay output for providing the time delayed input signal;
• an attenuation element having an input connected to said delay output, an output connected to said controller output and an attenuation control input for attenuating the signal at the output of said attenuation element;
• a static nonlinear circuit having an input connected to said control input and an output for providing a signal if the signal at the input of said static nonlinear circuit exceeds a defined threshold;
• and
• an integrator having an input connected to the output of said static nonlinear system and an output connected to the said attenuation control input for realizing a time characteristic of the controller matching psychoacoustic requirements.

A protection arrangement coupled to the electric input of a transducer which converts an electric signal into an acoustic or a mechanic signal for protecting said transducer against destruction at high signal amplitudes, comprising:

• a filter having a filter input connected with the input of said protection arrangement and a filter output for providing a monitored signal corresponding with the instantaneous load of said transducer;
• the transfer response of said filter being related to the transfer response of said transducer between the electric input signal and said monitored signal;
• a time delay element having an input connected with the input of said protection arrangement and an output for providing the time delayed input signal;
• an envelope detector having an input connected to said filter output and a detector output for providing a signal related with the envelope of said monitored signal;
• and
• a controller having a signal input connected to the output of said time delay element, a controller output connected to said electric input of said transducer and a control input connected to said detector output, said controller attenuating said delayed electric input signal if peak value of said monitored signal exceeds a defined limit, said time delay element allows to activate the controller in time to prevent an overload state of the transducer.