The world of electronic percussion is full of terms and acronyms that can be confusing to the player trying to add technology to his or her musical arsenal. Every electronic percussion rig contains a number of individual elements that fall into three main categories: controllers, sound modules, and audio systems. These devices create a symbiotic relationship that forms a musical marriage between the parts. We’re going to take a look at each of these three areas and see if we can demystify the jargon.
CONTROLLER: The controller is the instrument that you are playing. A controller reads the physical movements of the musician and turns those gestures into sound. Electronic percussion controllers can be based on acoustic instruments such as a drum, a conga, or even a vibraphone. Controllers can also take on interesting shapes and designs such a drumKAT, Zendrum, or Monome. (if you’re not familiar with these instruments, run a quick Google search). Most controllers will begin this magical musical process by generating MIDI data.
MIDI: MIDI (rhymes with “city”) is an acronym for Musical Instrument Digital Interface. MIDI is the digital language that is used for communication between different devices. MIDI messages consist of a number of different commands that, in total, can create an entire musical performance. MIDI messages are sent on one or more MIDI channels.
MIDI CHANNELS: There are 16 different MIDI channels. Each channel can be used to send messages to a specific sound-producing device or portion of software. For example, if you’re playing an electronic kit and you’re using a drum machine for a sound source, you’re likely to send messages over a single MIDI channel. But, if you want each pad in the kit to play a different instrument (such as bass, saxophone, synth, guitar, etc.), then you’ll likely have each pad send MIDI messages over unique MIDI channels. For example, channel 1 might carry the bass while channel 2 is dedicated to the saxophone sound. The most common MIDI message is the MIDI note-on message.
MIDI NOTE-ON: The MIDI language supports 128 different notes, or pitches, and each note is assigned a number. Note number 60 is assigned to “middle C.” So note number 61 is the C# above middle C while note number 50 is the D below middle C. When you strike a pad, the computer code inside the controller generates a Note-On message for a particular MIDI note number. For example, when you play the bass drum pad, the controller may create a Note-On message for note number 36. A large button on a Zendrum might generate a Note-On message for note number 67. Keep in mind that a particular note number and its corresponding pitch doesn’t always have to be an actual pitch. Depending on the way the sounds have been programmed, sending a particular MIDI note number might actually create the sound of a murmuring brook, a passing motorcycle, a nightmarish scream, or an entire symphony. Every MIDI note number contains a command for MIDI velocity.
Similar to the MIDI note numbers, the MIDI language is capable of generating 128 different velocity levels. Velocity is very closely aligned to volume, with the weaker strokes usually sending lower velocity values while stronger strokes generate higher values. Once the controller has generated a MIDI Note-On message with a MIDI note number and a MIDI velocity, you’ve got to have a way to turn a note off.
GATE TIME: Gate time is the amount of time a note is allowed to sound before it turns off. You can picture a physical gate with the sound moving through it. When you create an event, the gate opens. When the gate value is reached, the gate will close and the sound will stop. Gate times can be expressed in absolute values such as 6.2 seconds or as relative values such as 55 percent.
The most basic percussion controllers will let you program the MIDI channel, the MIDI note number, and the gate time. More advanced controllers often have special features that make them more flexible. Note alternate and note stack are the most common of these special abilities.
ALTERNATE: If your controller allows for this ability, you can program your surface to send a different MIDI note (perhaps even over a different MIDI channel) for a series of strokes. For example, if you set up a four-note alternate in your controller, you’ll be able to play a repeating pattern of different notes.