In a short period of time, the MX100A was superseded by the MX100B.

This early Disklavier model included fundamental features that have been included on every Disklavier since, such as tempo control, transposition, and connectivity with external MIDI devices. Pedal sensors on these early instruments, however, were limited to recording only two values: on and off (or fully down and fully up). MX100A PEThe MX100A featured a remarkably sophisticated recording system for its day, a system that included hammer sensors-an innovation that is not available on most player piano systems from other companies. The control unit was built into the cabinet. The first model Disklavier was the MX100A, which was available in a studio model upright called the U1. The record-and-playback system and its related features have changed substantially over the years, but one aspect of the Disklavier has remained constant: The Disklavier system has always been offered as a factory-installed system-never as a retrofit for existing pianos. The Disklavier is fundamentally a traditional, acoustic piano with a built-in record-and-playback system. At the time that the Disklavier was introduced, recordings were stored on 3 ½ inch floppy disks. The term Disklavier is a clever combination of the words disk (as in floppy disk) and Klavier, the German word for keyboard. In 1987, Yamaha took that concept to a new level of quality and ease of use by introducing the Disklavier reproducing piano to North America. In the 1970s, solenoid-based player systems were added to pianos for the first time. This dynamic history has been the result of the passionate interaction between keyboard players, composers, and instrument makers. The history of the piano is a history of technological change and innovation, starting over 300 years ago with the escapement action of Bartolomeo Cristofori and continuing with knee levers, pedals, action modifications, cast iron frame, and so much more.

Yamaha piano soft music