Most buying guides will tell you to consider what you intend to control and proceed from there. Sage advice, especially if, for example, you're a piano player and your intention is to get as close to the real feel of a piano as possible. In that case, you'd do well to find an 88-key, hammer-weighted keyboard with MIDI integration. You’ll find a vast selection of MIDI keyboard controllers that offer traditional acoustic piano touch while harnessing the power of MIDI control.
On the other hand non-keyboardists may feel more comfortable working with one of the many affordable MIDI pad controllers available these days. They make a great alternative to using a mouse and keyboard for controlling MIDI software with their ergonomically designed pads, knobs, and sliders that give you real hands-on control over MIDI.
With the huge array of MIDI controllers available today there’s one to match just about any musical ambition from saxophone-like wind controllers to electronic drum kits to audio mixers with MIDI integration, it's easy to find a controller that emulates your preferred instrument while staying within your budget.
All that's left is to hook it up properly to a signal generator of some sort—whether that’s computer software, an iOS device running audio apps or a rackmount synthesizer—and play! And with all the MIDI interfaces out there, getting your MIDI-enabled instruments and gear to talk to each other is no longer the challenge it once was. You’ll find interfaces designed to work with all the major interfaces such as USB, FireWire, as well as the various types of iOS device connectors.
It's amazing how far designers have brought the medium, both in terms of ease-of-use and flexibility. MIDI mapping capabilities in most DAWs, combined with control change templates within the controller itself, allow the user to almost instantly gain hands-on access to common control changes such as volume, panning, pitch bend, or modulation. Many controllers are ready to take command of specific DAW software right out of the box with little or no configuration.
For the average user, this is perfect. The beauty of MIDI is its basic simplicity, a simplicity that can, with a little imagination, provide you with almost infinite control of every MIDI device in your possession.
Simply put, Musical Instrument Digital Interface (MIDI) was created in order to allow digital instruments to talk to each other.
This communication may seem very mysterious, but in fact there are only a handful of basic processes at work. Before we get to the fun stuff, let's define some terms.
A MIDI message contains several pieces of data:
Channel – The voice, program, or timbre that the message will send the rest of the data to
Key – Defines which key or pad/trigger was activated
Velocity/Pressure – How hard the key or pad was hit or pressed, ranging in value from 0-127
Controller – Defines which knob or fader was activated
Controller Value – A fixed range from 0-127; generally speaking a fader pulled down has a value of 0 and a fader pushed up has a value of 127
Here are some examples of messages this data is contained in:
Note On/Note Off – A key, drum pad, or button is pressed/released
Key Pressure (Aftertouch) – After the 'Note On' message, additional pressure is placed on the key, generally activating some form of modulation
Controller Change – A knob, fader, or wheel is moved
Program Change – A new set of preset controls is activated
Channel Pressure – The channel or voice activated is defined by the amount of pressure or velocity
Applying MIDI to Various Applications
Now we can start to consider the many applications that this beautiful, simple concept can have. Here are some ideas to get you experimenting.
Multiple parameters assigned to the same knob: When working with software, most DAWs have some sort of MIDI mapping capability. This usually involves activating the MIDI map; choosing a parameter within a softsynth, such as filter cutoff; and then moving a knob or fader on the controller. Amazingly, that's it … for starters. What if you also mapped the delay rate to that same knob? Or the pitch? Or both? Because each softsynth uses the same channel language, a single knob can also be assigned to parameters within several plug-ins. Don't be afraid to customize your controls to fit the way you play; for example, a modulation wheel can be very useful as a crossfader. The procedure for accomplishing this varies by controller and DAW, so don't be afraid to dig into manuals and ask questions on user forums.
Breathe new life into menu-based (knobless) synths: If you've ever had the pleasure of programming a synth patch on a one line LCD screen with push buttons, you probably know how frustrating it can be to make a simple tweak to the patch you've created. The good news is that many of these boards have a list of controllable MIDI parameters that can be found in their manuals.
Many controllers have MIDI learning capabilities, but spending the time to program each parameter manually is well worth the trouble when you consider the flexibility of having dozens of knobs, faders, and pads to control DAW sounds, filters, and pitches.
Control your light show and music simultaneously: MIDI works just as well with visuals as it does with sound. A single controller can be linked to multiple pieces of software, as we mentioned, but don't limit yourself to just music programs! DJ and VJ controllers and DAW software can create a seamless show that includes sophisticated lighting programs. Using automation and motorized faders unleashes spectacular possibilities without even touching your controller during a performance. Imagine the cutoff for your master low-pass filter changing in sync with the spin and/or zoom of the projection behind you on stage, and you'll have a sense of how limitless this functionality really is.
Split keys and preset changes: One of the first applications of MIDI was to control several synths from the same keyboard. If you are in the market for a keyboard controller, it may be tempting to go for a smaller, more portable design. But consider the amount of synths you could have at your disposal with an 88-note keyboard controller where each octave is assigned to a different channel. Of course, the same results can be accomplished with a smaller board by moving through the octaves.