Example implementations relate to generating a performance index of an electrical device. An example implementation includes determining an acoustical contour of a soundscape within a computing enclosure for housing the electrical device. A performance response of the electrical device when subjected to the soundscape within the computing enclosure may be determined. Specifically, a soundscape may be generated within a test chamber that replicates the acoustical contour of the soundscape within the computing enclosure. A performance index of the electrical device may be generated upon being subjected to the generated soundscape.