
Owner's Manual – Viscount Cadet 21
Most instruments equipped with MIDI interface transmit MIDI messages which specify, for example, which note has
een played and with what dynamic, y means of the MIDI OUT connector. If this connector is connected to the MIDI
IN connector of another MIDI instrument, such as an expander, the second instrument will respond exactly to the notes
played on the transmitter instrument. The same type of information transfer is used for recording MIDI sequences. A
computer or a sequencer can e used to record the MIDI data generated y the transmitter instrument. If the recorded
data is sent ack to the instrument, it automatically repeats the recorded performance.
MIDI is a le to transmit a multitude of digital data y means of just one ca le, and thus just one connector. This is
thanks to the MIDI channels. There are 16 MIDI channels, and in a similar way as for radio communications in which
two stations can only communicate if they are tuned to the same frequency (or channel), two MIDI instruments
connected together are only a le to communicate if the transmitter instrument channel is the same as the receiver
instrument channel.
MIDI messages su divide into channel messages and system messages. The following is a short description of these
messages:
CHANNEL MESSAGES
NOTE ON
This message is transmitted when a note is pressed on the key oard. Each Note On message contains the following
information:
Note On: when a key has een struck;
Note Number: the key which has een pressed, and therefore the relative note played;
Velocity: note dynamic (i.e. the force applied when the key was struck).
Note messages are expressed as a num er from 0 to 127, with middle C represented y num er 60.
NOTE OFF
This message is transmitted when a key struck previously is released.
When it is received, the sound of the note relating to the key is switched off. Each Note On message contains the
following information:
Note Off: a key has een released;
Note Number: which key has een released;
Velocity: dynamic (i.e. how fast the note was released).
N.B.:
A Note On messa e with Velocity=0 is considered equivalent to a Note Off messa e.
PROGRAM CHANGE
This message is used to select the programs or sounds of the receiver instrument.
There is also a specific standard called General MIDI which descri es which sound should e recalled for each Program
Change received. This association is usually descri ed y means of a ta le included in the user manual of the
instrument which adopts the standard.
This message contains the following information:
Pro ram Chan e: voice or program change;
Pro ram Chan e Number: the num er of the program or voice to e activated;
CONTROL CHANGE
These are control messages (often associated to trimmers or pedals) used to add expression to the performance,
allowing you to set (and control in real time if necessary) voice parameters such as volume (CC n.7) or the position of
the expression pedals (CC n.11), etc.
This message contains the following information:
Control Chan e: a controller has een adjusted
Controller Number: which controller has een adjusted
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