Acoustic output devices

An acoustic output device, comprising:

• a housing;
• a first loudspeaker disposed in the housing, wherein the first loudspeaker includes a first diaphragm, and in the housing, a first front cavity and a first rear cavity are respectively disposed on a front side and a rear side of the first diaphragm, and the first front cavity and the first rear cavity are acoustically coupled with two hole portions disposed on the housing, respectively, to output a first sound wave and a second sound wave having a phase difference;
• and
• a second loudspeaker disposed in the housing, wherein the second loudspeaker includes a second diaphragm, and in the housing, a second front cavity and a second rear cavity are respectively disposed on a front side and a rear side of the second diaphragm, and only one of the second front cavity and the second rear cavity is acoustically coupled with a hole portion disposed on the housing to output a third sound wave, wherein in a target frequency range, the third sound wave, the first sound wave and the second sound wave are destructively superposed at a far-field position in a specific direction of the acoustic output device.