To make a musical piece under reproduction on the like retrievable after setting y enabling a user himself or herself to arbitrarily designate digest information.

A CPU 70 is connected to a DSP of a recorder having a memory card as a medium. When a reproducing button 84 is operated as prescribed in the reproducing state, index management information write processing is performed in parallel with the reproducing operation. In this processing, information which indicates the start position of an index part prescribed by timing of uer's depression of the reproducing button 85 and information indicating the duration of depression of the reproducing button 85 are generated in the CPU 70 and are written in a prescribed area of the memory card through the DSP as information indicating a reproducing section. Thus a user's favorite characteristic part or what is called a digest part is specified in a musical piece or the like in the middle of reproducing.