An uploader transmits to a server a request start notification indicating the start of a registration request and then transmits to the server a plurality of registration requests for pieces of music piece data. Upon receiving the plurality of registration requests from the uploader, the server registers the pieces of music piece data in a database in an HDD. After transmitting all the registration requests, the uploader transmits to the server a request completion notification indicating the completion of the registration requests. The server transmits an updating notification to an audio client after receiving the request completion notification. Therefore, traffic between the server and the client can be reduced when the server updates the database.