Music data processing apparatus and method

In a storage section (10), there are stored a plurality of music data sets of a given first format. Reproduction definition information defines reproducing order of a group of desired music data sets among the plurality of music data sets stored in the storage section and includes checkmarks indicating whether individual ones of the music data sets stored in the storage section are to be reproduced. On the basis of the reproduction definition information, all music data sets of the first format for which the checkmarks indicate that reproduction is to be performed are read out from the storage section (10) and automatically supplied as objects to be converted into a second format different from the first format.