A method for configuring a sound system in a confined passageway, comprising: installing a plurality of nodes with defined identities at intervals along said confined passageway, each node including a microphone, and two loudspeakers (203, 205) directed in substantially opposite directions along the confined passageway; establishing communication between each of said nodes and a control system computer; instructing a selected node from the plurality of nodes, to play a test sound using a selected one of its two loudspeakers at a first point in time determined by the control system computer and instructing the remaining nodes to register the test sound, said test sound including a predefined pattern at a predetermined time subsequent to the beginning of the test sound; detecting said predefined pattern at a second point in time by said remaining nodes instructed to register the test sound; for each node that has registered the test sound and detected the predefined pattern, computing a distance between said node instructed to play said test sound and said nodes instructed to register said test sound, based on the time it took for the predefined pattern to travel from the node instructed to play the test sound to the node instructed to register the test sound; determining the identity of the node closest to said selected node based on the computed distances; repeating the steps of instructing a selected node from the plurality of nodes to play the test sound and the remaining nodes to register the test sound, the step of detecting a predefined pattern, the step of computing a distance, and the step of determining the identity of the node closest to the selected node until a distance has been determined for each pair of adjacent nodes; and storing the relative positions of all nodes and the computed distance between all adjacent nodes in said control system computer. installing a plurality of nodes with defined identities at intervals along said confined passageway, each node including a microphone, and two loudspeakers (203, 205) directed in substantially opposite directions along the confined passageway; establishing communication between each of said nodes and a control system computer; instructing a selected node from the plurality of nodes, to play a test sound using a selected one of its two loudspeakers at a first point in time determined by the control system computer and instructing the remaining nodes to register the test sound, said test sound including a predefined pattern at a predetermined time subsequent to the beginning of the test sound; detecting said predefined pattern at a second point in time by said remaining nodes instructed to register the test sound; for each node that has registered the test sound and detected the predefined pattern, computing a distance between said node instructed to play said test sound and said nodes instructed to register said test sound, based on the time it took for the predefined pattern to travel from the node instructed to play the test sound to the node instructed to register the test sound; determining the identity of the node closest to said selected node based on the computed distances; repeating the steps of instructing a selected node from the plurality of nodes to play the test sound and the remaining nodes to register the test sound, the step of detecting a predefined pattern, the step of computing a distance, and the step of determining the identity of the node closest to the selected node until a distance has been determined for each pair of adjacent nodes; and storing the relative positions of all nodes and the computed distance between all adjacent nodes in said control system computer.