What is a MIDI Cable?

A musical instrument digital interface (MIDI) cable is used to connect digital instruments together, as well as to computers and recorders. MIDI is a form of electronic information produced by digital instruments. A MIDI cable allows this information to be sent to a computer or digital recorder for storage or recording. During playback, the MIDI cable carries this stored data back to the instrument. The instrument reproduces the sound based on the MIDI information.

A MIDI cable includes a length of insulated wire and a head made up of five pins. The most common MIDI cable is known as a male 5-pin din cable. The pins are arranged in a 180-degree semicircle. Only three of five of the pins are actively used. Pin 1 is not connected, pin 2 is the cable’s ground connection, and pin 3 is not connected. Pins 4 and 5 actively transfer MIDI data.

Several different lengths of cable are available. It is common for a MIDI cable to be 20 feet long (about 6 meters), or less, to work effectively. A high-quality cable may be needed if the user needs to a run the cable more than 20 feet between equipment. Data transferred long distances over lower quality cables may lose some integrity, or get broken up into digital pieces.

When musical instruments are connected together using MIDI, the cable will have MIDI connectors at both ends. Most computers do not have MIDI inputs or MIDI soundcards. As a result, if a MIDI instrument needs to be connected to a computer or other recording device, one end of the cable will have either a universal serial bus (USB) or FireWire connection at one end. An adapter can also be used to change a MIDI connector to either a USB or FireWire connector.

The device that is creating the MIDI information is called the master. Any device that is sent MIDI information to reproduce sound is known as a slave. The master can be either a musical instrument or a computer. Developments in software have allowed musicians to create MIDI music on a computer. A MIDI cable then sends the MIDI data to a keyboard or other instrument to create the sound.

The International MIDI Manufacturers Association introduced MIDI language standards in 1983, called MIDI Specification 1.0. These standards allowed all MIDI cables to work the same way, at the same speed. This standardization allows a musician to get similar results regardless of which brand of MIDI cable is used. In addition to sound, a MIDI cable can also be used to record and playback instructions for lighting sequences.