MIDI Musical Instrument Digital Interface What Is MIDI

MIDI Musical Instrument Digital Interface

What Is MIDI? § MIDI is an industry standard electronic communications protocol that defines each musical note or event in an electronic musical instrument performance § It allows electronic instruments, computers and other show equipment to share performance data in real time § MIDI does not transmit audio - it transmits data providing information such as the type and intensity of the musical notes and technical cues played during a performance

How MIDI Came About § As electronic instruments began to go digital a number of manufacturers developed digital interfaces which allowed their own digital instruments to work together, but did not permit interworking between devices developed by other manufacturers. § Dave Smith and Chet Wood, then working for a company called Sequential Circuits, devised a Universal Synthesizer Interface to overcome this problem (probably with some input from Roland). Their proposal was presented to the Audio Engineering Society in autumn 1981, and provided a starting point for the development of the Midi standard.

How MIDI Came About § Over the two years from autumn 1981 to 1983 most of the major manufacturers collaborated in the development of the first version of the MIDI standard (MIDI 1. 0), which was published in October 1983. § This included a hardware specification (how the data was to be transmitted and received I. e. the cables and connectors) and a data specification which described the format and its significance § At this time, the MMA (MIDI Manufacturers Association was set up with responsibility for development and maintenance of the standard

MIDI Basics § MIDI data, or messages, are usually triggered by a MIDI controller, such as a keyboard or a MIDI sequencer. § A MIDI controller is a device which is played as an instrument, and translates the performance into a MIDI data stream in real time (as it is played) § A MIDI sequencer is a device which allows MIDI data messages to be captured, stored, edited, combined, and replayed

MIDI Basics § MIDI communicates using simple messages for example, when a key is pressed on a controller keyboard, a note on message is relayed along with a note number and velocity information. This tells the sound module to start playing the selected sound at the correct note and volume. § When the key is released, a note off message is relayed. Other messages relayed include information regarding pitch bend, aftertouch (changes in pressure on the key without a note off occurring), program change and control change