Method for processing an audio signal (105, 105'), wherein the method comprises the following steps: - reading in the audio signal (105, 105'), - filtering the audio signal (105, 105') using a bandpass filter in order to obtain a bandpass filter signal; - performing analogue-to-digital conversion of the bandpass filter signal or of an audio signal derived from the bandpass filter signal in order to obtain an analogue-to-digital filter signal; - evaluating the analogue-to-digital filter signal using an expected value in order to obtain a control signal, wherein the expected value represents an expected signal parameter of the audio signal; and - driving the bandpass filter on the basis of the control signal in order to change a frequency passband of the bandpass filter from a first spectral passband to a second spectral passband, characterized in that, - in the filtering step, the signal is filtered using a further bandpass filter (BPFn) that differs from the bandpass filter in terms of a frequency passband in order to obtain a further bandpass filter signal, wherein the bandpass filters (BPF1, BPFn) obtain time windows of different lengths, and, - in the step of performing analogue-to-digital conversion, the further bandpass filter signal or a signal derived from the further bandpass filter signal is converted from analogue to digital in order to obtain a further analogue-to-digital filter signal, and, - in the evaluation step, the further analogue-to-digital filter signal is evaluated using a further expected value (E2, En) in order to obtain a further control signal, wherein the further expected value (E2, En) represents an expected signal parameter of the audio signal, and, - in the driving step, the further bandpass filter (BPFn) is driven on the basis of the further control signal in order to change a frequency passband of the further bandpass filter (BPFn) from a third spectral passband to a fourth spectral passband, wherein the control signal and the further control signal are output at different times. - reading in the audio signal (105, 105'), - filtering the audio signal (105, 105') using a bandpass filter in order to obtain a bandpass filter signal; - performing analogue-to-digital conversion of the bandpass filter signal or of an audio signal derived from the bandpass filter signal in order to obtain an analogue-to-digital filter signal; - evaluating the analogue-to-digital filter signal using an expected value in order to obtain a control signal, wherein the expected value represents an expected signal parameter of the audio signal; and - driving the bandpass filter on the basis of the control signal in order to change a frequency passband of the bandpass filter from a first spectral passband to a second spectral passband, characterized in that, - in the filtering step, the signal is filtered using a further bandpass filter (BPFn) that differs from the bandpass filter in terms of a frequency passband in order to obtain a further bandpass filter signal, wherein the bandpass filters (BPF1, BPFn) obtain time windows of different lengths, and, - in the step of performing analogue-to-digital conversion, the further bandpass filter signal or a signal derived from the further bandpass filter signal is converted from analogue to digital in order to obtain a further analogue-to-digital filter signal, and, - in the evaluation step, the further analogue-to-digital filter signal is evaluated using a further expected value (E2, En) in order to obtain a further control signal, wherein the further expected value (E2, En) represents an expected signal parameter of the audio signal, and, - in the driving step, the further bandpass filter (BPFn) is driven on the basis of the further control signal in order to change a frequency passband of the further bandpass filter (BPFn) from a third spectral passband to a fourth spectral passband, wherein the control signal and the further control signal are output at different times.