Performance data include at least a particular type of control parameter, like velocity data. Tones colors include ones of a first type for which the particular type of control parameter presents a first variation characteristic, and ones of a second type for which the control parameter presents a second variation characteristic. Environment setting data can be either set via a user's apparatus or received from another apparatus, and the environment setting data may include tone-color-change instructing information. When an automatic performance is to be executed on the basis of the performance data, a tone color of the performance data to be automatically performed is changed into a tone color corresponding to the instructing information. Tone color change instruction by the instructing information is invalidated, when the tone color be changed between tone colors of the first and second types.