Example audio signal processing apparatuses and methods for processing an input audio signal into an output audio signal are disclosed. An example audio signal processing apparatus comprises a decomposer configured to decompose the input audio signal into a direct audio signal and a diffuse audio signal, a modifier configured to modify the direct audio signal in order to obtain a modified direct audio signal, wherein the modifier comprises a bandwidth extender configured to extend an upper cutoff frequency of a frequency range of the direct audio signal, and a combiner configured to combine the modified direct audio signal with the diffuse audio signal to obtain the output audio signal.