Audio Signal Processing Apparatus and Speaker Apparatus

An audio signal processing apparatus comprising:

• an acquiring unit which acquires an input audio signal;
• a first filtering unit which outputs the audio signal acquired by the acquiring unit while attenuating frequency components of the audio signal except for frequency components of a first preset frequency band;
• a detecting unit which detects a sound volume level of the audio signal output from the first filtering unit;
• an amplitude limiting unit which calculates an amplitude limiting level corresponding to the sound volume level detected by the detecting unit, and which limits a waveform of the audio signal output from the first filtering unit, an amplitude of the limited waveform being equal to or higher than the amplitude limiting level, thereby outputting an audio signal to which harmonics are added;
• a second filtering unit which outputs the audio signal output from the amplitude limiting unit while attenuating frequency components of the audio signal except for frequency components of a second preset frequency band including at least a part of the frequency band of the audio signal output from the first filtering unit, and a part of the frequency band of the harmonics;
• a compressing unit which outputs the audio signal output from the second filtering unit while compressing a dynamic range of the audio signal;
• and
• an adding unit which adds the audio signal output from the compressing unit to the input audio signal, and which outputs a result of the addition.