A combined digital audio file player and modulator. In one embodiment, the invention is an apparatus comprising: an elongate housing having a distal end and a proximal end; a socket power adapter located at a distal end of the elongate housing; an interface port in the housing for receiving an external memory device; a user control panel located on the housing at or near the proximal end; a circuit located within the elongate housing and operably coupled to the socket power adapter, the interface port, and the user control panel; and the circuit comprising a processor for retrieving an audio data file stored in a digital format on an external memory device that is in operable cooperation with the interface port, a decoder for decoding the retrieved audio data files, and a transmitter for transmitting the decoded audio data files to a radio tuner. In another embodiment, the invention can be a modulator that transmits data to a radio receiver or digital tuner, comprising multiple input ports or jacks and a signal converter device to transmit the data to the radio receiver or the digital tuner. Still another embodiment of the modulator reproduces compressed audio data; the modulator comprises a housing, an apparatus in the housing to accommodate an external storage device, a mechanism for instructing the modulator to execute an operation, a processing device for reading a data file on the external storage device and a converter to transmit the data to a receiver or digital tuner.