O2: A Network Protocol for Music Systems

Figure 5

Control panel for the Conductor of the CMU Laptop Orchestra. The top left window is a map of the stage showing the locations of all the players (only 2 are shown here). The circle moves to indicate the beat and tempo. At middle left are controls for tempo, meter, harmony, and style, which are sent to all players when the COMMIT button is pressed. At the bottom is a chat window allowing players to communicate during the performance. The conductor also has a number of standard chord progressions that can be selected below “Harmony” (top, center). When players join the ensemble, their names are displayed in a list. To the left of each name is a solo (S) and mute (M) button; to the right are softer (<) and louder (>) buttons surrounding the current loudness offset (0 in this example).