10.6

1181Logic Pro User Guide
metadata Refers to additional descriptive information that is stored in the file header of a
number of file types (AAF, for example). Metadata is used to reference external media, to
simplify searches, and more.
metronome A device that produces a regular, metrical tick or other sound to mark the
musical beat (in bpm). Logic Pro features a metronome for practice and recording. It can
be configured in the Metronome project settings.
MIDI Acronym for Musical Instrument Digital Interface. MIDI provides a standardized
hardware and software interface for electronic musical instruments, allowing devices such
as synthesizers and computers to communicate with each other. It controls the pitch,
length, and volume of a musical note event, among other characteristics.
MIDI channel Tracks recorded in Logic Pro can be directed to different MIDI channels,
which can contain different information and play back through different sounds assigned to
each channel; for example, channel 1:piano, channel 2:bass, channel 3:strings, and so on.
Up to 16 separate MIDI channels can pass through a port simultaneously, if the receiving
devices are capable of receiving data on more than one channel and are capable of playing
back different sounds simultaneously. See also multitimbral.
MIDI Clock A short MIDI message for clock signals used to provide a timing pulse between
MIDI devices. MIDI Clock is accurate to 24 ppqn (pulses per quarter note), although some
devices interpolate these pulse values, resulting in a more precise clock signal if each
device is capable of interpreting this additional information correctly. See also SPP.
MIDI In button The button used to turn on Step Input mode in the editors. See also Step
Input function.
MIDI interface A hardware component that allows you to connect MIDI controllers and
other MIDI devices to your computer. See also audio interface.
MIDI Machine Control (MMC) A set of MIDI commands that Logic Pro uses to control the
transport functions of any MMC-capable tape machine. The recording process can also be
controlled and automated from Logic Pro via MMC.
MIDI message A message transmitted via MIDI that consists of one status byte and zero,
one, two, or many data bytes (with system exclusive commands). See also event.
MIDI Multi mode A multi-timbral operating mode on a MIDI sound module where different
sounds can be controlled (polyphonically) on different MIDI channels. A multi mode sound
module behaves like several polyphonic sound modules. General MIDI describes a 16-
part multi mode (the ability to control 16 different parts individually). Most modern sound
generators support multi mode. In Logic Pro, multi mode sound modules are addressed
via multi-instrument objects. This MIDI mode and multi mode sound modules are generally
referred to as multi-timbral. See also multitimbral.
MIDI plug-inMIDI plug-ins can be inserted in software instrument channel strips to
process or generate MIDI data played from a MIDI region or a MIDI keyboard in real time.
Logic Pro MIDI plug-ins include Arpeggiator, Chord Trigger, and Modulator, as well as
Scripter which lets you to create your own MIDI processing and generation scripts.
MIDI region A data container for MIDI events, shown in the Tracks area as a rounded
rectangular area.
MIDI Thru tool A tool in the Environment used to assign an Environment object to the
selected track in the Tracks area.