In an apparatus having a display for supplying parameters to a mixing system, a first display control section controls the display to present a scene list containing identifications of each scene and configuration data of the mixing system specified by first specification data contained in each scene. A scene selection acceptance section accepts selection of a scene from the scene list presented on the display. A second display control section controls the display to present operation data of the mixing system specified by second specification data contained in the selected scene, such that the display presents each portion of the operation data. Each portion contains one option of the operation data specified by the second specification data in manner distinguishable from another option not specified by the second specification data.