DigiDesign Digidesign Pro Tools 8.0, Справочное руководство

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Pro Tools Reference Guide 10
MIDI Port
A physical MIDI port on a MIDI inter-
face or a virtual MIDI port created in software.
There are separate ports for MIDI In and Out.
Physical MIDI ports connect to external MIDI
devices using MIDI cables. Virtual MIDI ports
connect software plug-ins and applications (see
also “Virtual MIDI Nodes”).
MIDI Channel
Up to 16 channels of MIDI perfor-
mance data can be transmitted on a single MIDI
cable. The channel number separates the differ-
ent messages so your sound sources can receive
the correct messages.
Program Change Event A MIDI command that
tells a sound source which of its sounds (or
sound patches) to use. The MIDI protocol lets
you choose from a range of 128 patches.
Bank Select Message
Many devices have more
than 128 patches, which are arranged in banks.
The Bank Select Message is a MIDI command
that specifies the bank of patches from which to
choose.
Local Control A controller setting found on most
MIDI keyboards that lets them play their own
sound source. Disabling “local control” ensures
that a device’s internal sound source is only
played by external MIDI messages (such as those
sent from Pro Tools when MIDI in Pro Tools is
routed to the MIDI keyboard). When using
Pro Tools, “local control” should usually be dis-
abled (for example, when using MIDI Thru).
When “local control” is off, your keyboard still
transmits data to its MIDI OUT port.
Continuous Controller Events
MIDI instructions
that allow real-time changes to notes that are
currently sounding. These include pitch bend,
modulation, volume, pan, and many others.
System Exclusive Data
MIDI data commonly
used for sending and retrieving patch parameter
information for storage purposes.
Virtual MIDI Nodes
When using MIDI with in-
strument plug-ins in Pro Tools, virtual MIDI
nodes are created. These nodes act like MIDI
ports and provide software MIDI connections
between Pro Tools and other MIDI software,
such as instrument plug-ins. For example, when
you insert Propellerhead’s Reason as a ReWire
client on a track, the various MIDI inputs to
Reason become available to Pro Tools MIDI and
Instrument track MIDI outputs.
Common MIDI Misconceptions
MIDI is not audio, and by itself makes no sound.
MIDI is control information only. It is like the
piano roll for a player piano; it provides control
information for what note to play when, for
how long, at what volume, and with what
sound (instrument). For example, when you
strike a key on a MIDI keyboard, it sends a mes-
sage to a MIDI instrument to play that particular
note at that particular velocity using the se-
lected sound (instrument). This could be its in-
ternal tone generator (like a synthesizer or sam-
pler), another external MIDI instrument, or an
instrument plug-in within Pro Tools. In order to
play and hear a MIDI recording, you must have
a MIDI instrument. Audio from an external
MIDI instrument can be sent to an external
mixer or monitored through your Pro Tools au-
dio interface (using either an Instrument track
or Auxiliary track).
If you are using an external MIDI instrument, it
must be connected to MIDI ports that are recog-
nized by your computer. These ports can be on a
Pro Tools interface that has MIDI ports (such as
an Mbox
®
2) or some other MIDI interface (such
as a Digidesign MIDI I/O).