Abstract: The amplifier comprises a power suppl, a current sensing element for sensing a current in the current path of the power supply, a detecting circuit responsive to the current sensing element, and voltage reducing means for reducing the signal amplitude of at least one of the audio signals in response to the detection circuit. The detecting circuit comprises in a preferred embodiment a threshold circuit, and when the current in the current path of the power supply is above a predefined threshold, the detection circuit together with the voltage reducing means reduce at least the signal amplitude of one of the audio channels. The current sensing element is for example a current sensing resistor and the detecting circuit is a voltage detection circuit in parallel to this resistor. The voltage reducing means comprise advantageously two diodes for each channel, via which a positive and a negative voltage limit is applied to the signal path of the audio signals.