The present application provides a method of audio signal processing. The method comprises obtaining a voice coil direct current resistance of a speaker. The method further comprises obtaining an audio input signal to be input into the speaker. The method further comprises determining an audio input power based on the voice coil direct current resistance and the audio input signal. The method further comprises obtaining a thermal model of the speaker, and determining a transient power threshold based on the audio input power and the thermal model. The method further comprises determining a power constraint gain based on the audio input power and the transient power threshold. The method further comprises obtaining a voice coil temperature of the speaker. The method further comprises determining a temperature constraint gain based on the voice coil temperature and an upper operating temperature limit of the speaker. The method further comprises adjusting the audio input signal based on the power constraint gain and the temperature constraint gain, to obtain a target signal.