An audio processing method , comprising: causing , by a control system , a first gap to be inserted into a first frequency range of first audio playback signals of a content stream during a first time interval of the content stream to generate first modified audio playback signals for a first audio device of an audio environment , the first gap comprising an attenuation of the first audio playback signals in the first frequency range; causing , by the control system , the first audio device to play back the first modified audio playback signals, to generate first audio device playback sound; causing , by the control system , the first gap to be inserted into the first frequency range of second audio playback signals of the content stream during the first time interval of the content stream to generate second modified audio playback signals for a second audio device of the audio environment ; causing , by the control system , the second audio device to play back the second modified audio playback signals, to generate second audio device playback sound; causing , by the control system , at least one microphone of the audio environment to detect at least the first audio device playback sound and the second audio device playback sound and to generate microphone signals corresponding to at least the first audio device playback sound and the second audio device playback sound; extracting , by the control system , audio data from the microphone signals in at least the first frequency range, to produce extracted audio data; and estimating , by the control system , a far-field audio environment impulse response based, at least in part, on the extracted audio data. causing , by a control system , a first gap to be inserted into a first frequency range of first audio playback signals of a content stream during a first time interval of the content stream to generate first modified audio playback signals for a first audio device of an audio environment , the first gap comprising an attenuation of the first audio playback signals in the first frequency range; causing , by the control system , the first audio device to play back the first modified audio playback signals, to generate first audio device playback sound; causing , by the control system , the first gap to be inserted into the first frequency range of second audio playback signals of the content stream during the first time interval of the content stream to generate second modified audio playback signals for a second audio device of the audio environment ; causing , by the control system , the second audio device to play back the second modified audio playback signals, to generate second audio device playback sound; causing , by the control system , at least one microphone of the audio environment to detect at least the first audio device playback sound and the second audio device playback sound and to generate microphone signals corresponding to at least the first audio device playback sound and the second audio device playback sound; extracting , by the control system , audio data from the microphone signals in at least the first frequency range, to produce extracted audio data; and estimating , by the control system , a far-field audio environment impulse response based, at least in part, on the extracted audio data. <EOS>