A data reproducing system of the invention includes a data transmitter for transmitting a data signal containing audio data by air and a data receiver for receiving the data signal by air from the data transmitter. The data receiver includes a data receiving section for receiving a data signal by air, a receiving ROM for storing specific apparatus-specific ID in advance, data extraction member for extracting the apparatus-specific ID contained in the data signal received by air, data determination member for determining whether the extracted apparatus-specific ID is in a predetermined relationship with the apparatus-specific ID stored in the receiving ROM, and reproducing member for extracting audio data from the data signal received by air and regenerating the audio data on a decoding section once the predetermined relationship is determined.