Each device of a group of devices, in particular voice-controlled devices, is equipped with sound receivers and emitters and a short-range radio communication subsystem. Each device is caused to emit a test sound and, via its communications subsystem, a related timing-reference signal. Each device receiving a test sound and related timing-reference signal determines the transit time of the test sound. Using the measured transit times, the devices determine their distances one from another and, by exchanging these distances, the devices, or at least one of them, calculates the relative locations of all devices.