Acoustic output device

An acoustic output device, comprising:

• a first acoustic driver including a first diaphragm;
• a second acoustic driver including a second diaphragm;
• a third acoustic driver including a third diaphragm;
• a control circuit electrically connected with the first acoustic driver and the second acoustic driver respectively, wherein
• the control circuit provides a first electrical signal for driving a vibration of the first diaphragm, and a second electrical signal for driving a vibration of the second diaphragm, and the control circuit is configured to adjust a phase of the first electrical signal and a phase of the second electrical signal such that, in a first scenario, the phase of the first electrical signal and the phase of the second electrical signal are opposite, and in a second scenario, the phase of the first electrical signal and the phase of the second electrical signal are same;
• and
• a housing supporting the first acoustic driver and the second acoustic driver, wherein
• a sound generated by the vibration of the first diaphragm is radiated outward through a first sound guide hole on the housing, and a sound generated by the vibration of the second diaphragm is radiated outward through a second sound guide hole on the housing;
• wherein the control circuit provides a third electrical signal;
• in the first scenario, a medium-high frequency signal in the third electrical signal is filtered out by a filter or a filter group connected with the third acoustic driver, and a remaining low frequency signal in the third electrical signal is sent to the third acoustic driver for driving a vibration of the third diaphragm to generate a low-frequency sound, and the low-frequency sound is radiated outward through a third sound guide hole and a fourth sound guide hole on the housing;
• in the second scenario, the filter or the filter group is turned off, the third acoustic driver generates the low-frequency sound and a medium-high frequency sound according to the third electrical signal, the medium-high frequency sound radiates toward or away from an ear of a user through the third sound guide hole and the fourth sound guide hole, to increase a volume of the medium-high frequency band output by the acoustic output device.