MIDI controllers come in a variety of forms, ranging from a simple set of faders to realistically complex musical instruments. Perhaps the most common form of MIDI controller consists of a small, piano-style keyboard with a series of buttons, knobs and faders. MIDI drum machines employ a set of pads which you can use to tap out drum beats; other MIDI instruments resemble saxophones, guitars or drum kits. Specialized DJ MIDI controllers are designed for mixing audio using DJ software and include turntable and crossfader controls. No matter what form they take, all MIDI controllers work in the same way. When you move a control on the device, the controller translates this movement into a MIDI signal and transmits it to your computer.
MIDI controllers are useful both for live performances and when recording in the studio. In a live setting, playing music with a MIDI controller can add some much-needed energy to electronic music performances. Rather than tapping away at a laptop keyboard on stage, you can play a synthesizer on your laptop using a MIDI guitar. When you're composing music in the studio, recording a series of notes using a MIDI instrument can yield a much more natural sound than using the mouse to enter them into the software. In both cases, MIDI controllers allow you to control the software in ways that would otherwise be impossible. You can, for example, move two volume controls simultaneously using a MIDI controller.
Before you can start using a MIDI controller, you must configure it to work with your audio software. Connect the controller to your computer, install any drivers that the controller requires, and then enable it in your audio software. Once the software recognizes your controller, you can send musical note data from the controller to the software by, for example, pressing a key on the piano keyboard. To use any other MIDI functions, however, you'll need to map the controls on the device to the controls in the program.
To "map," or associate, a button, knob or fader on the MIDI controller with a control in your audio software, enable the software's MIDI mapping mode. Click on a virtual knob, slider or other element of the software, then move the element of the MIDI device with which you want to control that parameter. If, for example, you want to raise and lower the master volume using the first fader on the MIDI controller, click the master volume control, then move the fader up and down. Many audio programs include preset mapping templates for commonly used MIDI controllers. In this case, you can load the template instead of mapping controls manually.