| 摘要 |
An apparatus, method and computer program where the apparatus comprises: a filter configured to filter an electrical input signal and provide a filtered electrical input signal to an audio output device; an audio output device configured to convert the filtered electrical input signal to an acoustic output signal; a microphone configured to detect an acoustic signal and provide an electrical output signal corresponding to the detected acoustic signal; and a detector configured to receive the filtered electrical input signal provided to the audio output device as a first input and the electrical output signal provided by the microphone as a second input; wherein the detector is configured to detect a change in the signal power of the electrical output signal provided by the microphone relative to the filtered electrical input signal provided to the audio output device and, in response to the detection of the change in the signal power, provide a control signal to the filter to control the filter to compensate for the detected change in signal power. |
