An audio processing device includes: a signal processing circuit configured to select between a first state for outputting a first signal obtained by reducing components that fall below a first frequency in an audio signal and a second state for outputting a second signal obtained by reducing components that fall below a second frequency in the audio signal, and output one of the selected first or second signal as an output signal, where the second frequency is higher than the first frequency; a class-D amplifier that amplifies the output signal; a processor configured to: determine whether or not an intensity of a low-frequency component in the audio signal exceeds a threshold value; and control the signal processing circuit to select: the first state in a case where a determination result is negative, where the intensity of the low-frequency component in the audio signal is determined to not exceed the threshold value; and the second state in a case where the determination result is affirmative, where the intensity of the low-frequency component in the audio signal is determined to exceed the threshold value.