An audio-visual device comprising: a housing comprising a top end that comprises an opening and which has a space provided therein; a display comprising a display area for displaying video contents; a lifter; a speaker; a motor controller configured to control the lifter, and a controller configured to control the display to display an image on the display area of the display and output sound through the speaker, wherein the display area of the display is disposed by the motor controller in one of at least three height positions: a first height position where the display area of the display is not exposed from the top end of the housing; a second height position where the display area of the display is completely exposed from the top end of the housing; and a third height position where a partial portion of the display area of the display is moved upward out of the housing through the opening of the top end of the housing such that the partial portion of the display area of the display is maintained in a vertically standing position outside the housing, and wherein the controller is further configured to: output only sound through the speaker without displaying an image in a state where the display area of the display is disposed by the motor controller in the first height position; and output information of the sound on the partial portion of the display area of the display when the display area of the display is disposed by the motor controller in the third height position. a housing comprising a top end that comprises an opening and which has a space provided therein; a display comprising a display area for displaying video contents; a lifter; a speaker; a motor controller configured to control the lifter, and a controller configured to control the display to display an image on the display area of the display and output sound through the speaker, wherein the display area of the display is disposed by the motor controller in one of at least three height positions: a first height position where the display area of the display is not exposed from the top end of the housing; a second height position where the display area of the display is completely exposed from the top end of the housing; and a third height position where a partial portion of the display area of the display is moved upward out of the housing through the opening of the top end of the housing such that the partial portion of the display area of the display is maintained in a vertically standing position outside the housing, and wherein the controller is further configured to: output only sound through the speaker without displaying an image in a state where the display area of the display is disposed by the motor controller in the first height position; and output information of the sound on the partial portion of the display area of the display when the display area of the display is disposed by the motor controller in the third height position. a first height position where the display area of the display is not exposed from the top end of the housing; a second height position where the display area of the display is completely exposed from the top end of the housing; and a third height position where a partial portion of the display area of the display is moved upward out of the housing through the opening of the top end of the housing such that the partial portion of the display area of the display is maintained in a vertically standing position outside the housing, and wherein the controller is further configured to: output only sound through the speaker without displaying an image in a state where the display area of the display is disposed by the motor controller in the first height position; and output information of the sound on the partial portion of the display area of the display when the display area of the display is disposed by the motor controller in the third height position. output only sound through the speaker without displaying an image in a state where the display area of the display is disposed by the motor controller in the first height position; and output information of the sound on the partial portion of the display area of the display when the display area of the display is disposed by the motor controller in the third height position.