I figured that before I dive into the musical capabilities of the iPad, it might not hurt to define some of these terms and acronyms that I’m tossing around. As with any field, electronic music has its own jargon that can be quite confusing. These are roughly in order of how frequently I’ll be using the terms over the next several posts. I don’t pretend to be an expert, and will probably get some of this wrong, but here goes…
Musical Instrument Digital Interface (MIDI) – MIDI was developed as a communications protocol in the late 1970’s, early 1980’s. It allows musical keyboards to control other keyboards and devices such as computers, etc.
Even though it was developed thirty years ago, MIDI is still very much in use. Back in the day when computers didn’t have much memory, MIDI was also a very efficient way to create complex compositions. A computer or external sequencer only had to record key-on/key-off, pitch, and duration data. The actual sounds were produced by the external keyboards or sound modules. Other capabilities were added to the protocol, such as the ability to detect velocity, or how hard a key is pressed, and the ability to control various settings on instruments such as sustain, and to trigger events such as changing lighting, changing settings, etc. You could also play multiple keyboards from one controller keyboard, creating thick sounds and tonalities from multiple instruments.
MIDI has 16 different channels, and different instruments can be assigned to various channels. On most keyboards you will find a MIDI in, out, and through port. On many modern keyboards the MIDI signal is now transmitted through a USB port.