Keyboards capable of receiving and transmitting audio files have musical instrument digital interface (MIDI) ports. The first digital keyboards with MIDI ports required the separate purchase of a MIDI interface if files were to be transferred to and from a computer. The interface acted as an adaptor with inputs for both MIDI connectors and USB cables. Roland set a music production precedent with the creation of the first digital keyboard equipped with USB MIDI ports that allow for the transferrance of audio files with a single USB cable, according to RolandUS.com. This creation has made the manufacture of MIDI port only keyboards obsolete. Writer Bio
