Abstract: The present disclosure discloses a telephone set and a method of controlling off-hook/on-hook state of a telephone set, and belongs to the field of communications devices. The telephone set includes a handle and a host, where the handle includes a first switch, and the host includes a second switch. According to the present disclosure, the first switch is added on the handle of the telephone set, the second switch is correspondingly added into the host of the telephone set, and a state of the first switch is used to control the second switch to send an off-hook/on-hook signal, so as to enable the telephone set to be off-hook/on-hook.

Abstract: The present invention relates to the field of signal processing technologies, and provides an audio signal playback system and an electronic device. The system includes: two or more loudspeakers, configured to separately play audio signals in different frequency bands; a filter unit, configured to filter an input audio signal, amplify the filtered audio signal, and output the amplified audio signal to the two or more loudspeakers; and a feedback control unit, configured to collect the audio signals played by the two or more loudspeakers, measure power values of the audio signals in different frequency bands, and adjust, according to an measurement result, a amplification factor of the filter unit for the filtered audio signal in a corresponding frequency band.

Abstract: The present disclosure discloses a telephone set and a method of controlling off-hook/on-hook state of a telephone set, and belongs to the field of communications devices. The telephone set includes a handle and a host, where the handle includes a first switch, and the host includes a second switch. According to the present disclosure, the first switch is added on the handle of the telephone set, the second switch is correspondingly added into the host of the telephone set, and a state of the first switch is used to control the second switch to send an off-hook/on-hook signal, so as to enable the telephone set to be off-hook/on-hook.