Acoustic output devices

An acoustic output device, comprising:

• a sound generation component configured to accommodate a sound generation unit that produces a sound;
• an earhook, one end of the earhook being connected to the sound generation component and disposing the sound generation component near an ear without blocking an earhole, the other end of the earhook being connected to a target warehouse body, in a wearing state of the acoustic output device, the sound generation component and the target warehouse body being located on both sides of the ear;
• and
• a sensor including a first ultrasonic transducer and a second ultrasonic transducer respectively disposed inside the sound generation component and the target warehouse body, the sensor being configured to transmit, through one of the first ultrasonic transducer and the second ultrasonic transducer, an ultrasonic signal to the other of the first ultrasonic transducer and the second ultrasonic transducer and detect, through the other of the first ultrasonic transducer and the second ultrasonic transducer, the ultrasonic signal, the sensor being further configured to determine the wearing state of the acoustic output device based on the detection, wherein when a change of the wearing state of the acoustic output device causes a change in the ultrasonic signal detected by the sensor, an output state of the acoustic output device changes.