87
Appendices
Appendices
About MIDI
MIDI is an acronym for Musical Instrument Digital Interface,
and is a world-wide standard for allowing electronic musical
equipment to communicate by transmitting messages such as
performance information and sound selections. Any MIDI
equipped device is able to transmit applicable types of data
to another MIDI equipped device, even if the two devices are
different models or were made by different manufacturers.
In MIDI, performance information such as playing a key or
pressing a pedal are transmitted as MIDI Messages.
How MIDI messages are
transmitted and received
First, we will explain briefly how MIDI messages are
transmitted and received.
MIDI connectors
The following types of connector are used to convey MIDI
messages. MIDI cables are connected to these connectors as
needed.
fig.09-010
* The GT-8 features both “MIDI IN” and “MIDI OUT” connectors.
MIDI channels
MIDI is able to independently control more than one MIDI
device over a single MIDI cable. This is possible because of
the concept of MIDI channels.
The idea of MIDI channels is somewhat similar to the idea of
television channels. By changing channels on a television set,
you can view a variety of programs. This is because the
information of a particular channel is received when the
channels of the transmitter and receiver match.
fig.09-020
MIDI has sixteen channels 1–16, and MIDI messages will be
received by the instrument (the receiving device) whose
channel matches the channel of the transmitter.
* If omni mode is on, data of all MIDI channels will be received
regardless of the MIDI channel setting. If you do not need to
control a specific MIDI channel, you may set Omni On.
Main types of MIDI message
used by the GT-8
MIDI includes many types of MIDI messages that can convey
a variety of information. MIDI messages can be broadly
divided into two types; messages that are handled separately
by MIDI channel (channel messages), and messages that are
handled without reference to a MIDI channel (system
messages).
Channel messages
These messages are used to convey performance
information. Normally these messages perform most of the
control. The way in which a receiving device will react to
each type of MIDI message will be determined by the
settings of the receiving device.
Program change messages
These messages are generally used to select sounds, and
include a program change number from 1 to 128 which
specifies the desired sound. The GT-8 also allows you to
select any of the 340 different patch numbers in conjunction
with bank select messages; a type of control change message.
Control change messages
These messages are used to enhance the expressiveness of a
performance. Each message includes a controller number,
and the settings of the receiving device will determine what
aspect of the sound will be affected by control change
messages of a given controller number.
The specified parameters can be controlled with the GT-8.
System messages
System messages include exclusive messages, messages used
for synchronization, and messages used to keep a MIDI
system running correctly.
Exclusive messages
Exclusive messages handle information related to a unit’s
own unique sounds, or other device-specific information.
Generally, such messages can only be exchanged between
devices of the same model by the same manufacturer.
Exclusive messages can be employed to save the settings for
effects programs into a sequencer, or for transferring such
data to another GT-8.
The two instruments must be set to the same device ID
numbers when exchanging SysEx messages.
MIDI IN:
This connector receives messages from an-
other MIDI device.
MIDI OUT
This connector transmits messages from this
device.
MIDI THRU
This connector re-transmits the messages
that were received at MIDI IN.
Broadcasting
Station A
T.V. information from many different broadcasting station is
sent through an antena.
Select the channel of the broadcasting
station you wish to watch
Broadcasting
Station B
Broadcasting
Station C
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