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MIDI Data Format■ What is MIDI?
MIDI stands for Musical Instrument Digital
Interface, a sophisticated system that allows
various electronic musical instruments and other
devices to “communicate” with each other. This
is done by sending and receiving MIDI
messages over a MIDI cable.
Since MIDI has such as a broad scope and so
many different uses, it would be impossible to
explain everything here. However, if you’re a
MIDI “novice,” the brief explanations below
will give you a good start in understanding this
powerful and flexible technology.
■ MIDI Messages
The MU15 is controlled by various types of
MIDI messages. Using them in song data on a
sequencer or from a MIDI keyboard, you can:
• Determine the Sound Module mode• Select MIDI channels, Voices and effects• Play the Voices• Edit the Parts and change parameter values• Edit the effects● Note On/Off (Key On/Off)
These tell the MU15 which notes to play and
how long they are to be played. Velocity values
let you change the dynamics or level of the
sound, depending on how strongly you play the
keys.
● Program Change
These messages determine which Voice is
selected for each Part, and they can be inserted
at any desired location in the song. Used with
Bank Select messages, they let you access any
of the 676 Voices of the MU15.
● Control Change
These messages provide powerful, real-time
control over various aspects of the sound —
including volume, pan position, sustain,
modulation, brightness, portamento time, effect
depth, and many others. Depending on the
controllers available on your particular MIDI
instrument and their Control Change number
assignments, you can use key velocity,
aftertouch (see below) foot controllers, pedals,
sliders, performance wheels, and joysticks to
control these aspects of the sound.
● Pitch Bend
These messages let you continuously raise or
lower the pitch of the Voices as you play. They
are usually controlled with a pitch bend wheel
on a MIDI keyboard.
● Aftertouch
This is a pressure sensing function that lets you
control an assigned aspect of the sound by the
strength with which you press the keys. The
MU15 responds to both Channel (global) and
Polyphonic (individual keys) Aftertouch.
● System Exclusive
These messages let you delve even deeper into
the inner workings of the MU15, letting you
control the master volume and tuning, Sound
Module mode (XG or TG300B), Part param-
eters, effect types and parameters, and various
other settings.
One of the best and easiest ways to use System
Exclusive messages is with Yamaha’s XGworks
software. The included XG Editor window lets
you view and edit all of the MU15 parameters
from your computer. Special “Detail” buttons
on the main window give you comprehensive
control over the Parts, Drum Setups, and effects.
The changes you make are instantaneous, and
you can save all your custom settings for future
recall as System Exclusive data, either directly
to the current song or as a special XG Parameter
file.
NOTEThe XG Editor in XGworks has additional parameters (for otherXG instruments) that are not available on the MU15.10
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Dec Hex Dec Hex Dec Hex Dec Hex Dec Hex Dec Hex Dec Hex Dec Hex
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