A sound output device and method are provided. The device includes a first speaker and a second speaker; a first coupling unit and a second coupling unit which can be coupled to the first coupling unit; a sensor module for sensing at least one of a coupling state between the first coupling unit and the second coupling unit, a separation distance, and a separation time; a communication module for forming a communication channel with an electronic device; and a processor for receiving sound information corresponding to a sound output function from the electronic device, generating control information for controlling the sound output function on the basis of at least one of the coupling state between the first coupling unit and the second coupling unit, the separation distance, and the separation time, and transmitting the generated control information to the electronic device.