An information producing apparatus is constructed for producing a combination of object information providing substantial contents and performance information providing a music piece in association with the substantial contents. In the information producing apparatus, a source section provides the object information having substantial contents. An extracting section analyzes the provided object information to extract therefrom the characteristic information which is characteristic of the substantial contents of the provided object information. An attaching section operates based on the extracted characteristic information for attaching performance information to the provided object information. On the other hand, an information reproducing apparatus utilizes the attached performance information to provide a performance of a music piece as a music effect in association with the substantial contents when reproducing the object information transmitted from the information producing apparatus.