User Guide

32
MIDI also allows for more than one instrument to
sound at the same time, as in an ensemble or an
orchestra. A single MIDI cable can send messages
on up to 16 channels at a time, allowing for up to
16 different “instruments” to sound at once. A
General MIDI synthesizer (like the sounds in the
Control Module) contains a standard set of sounds
that are arranged in a standard list, called a bank.
Each bank has 128 sounds, called Programs. A
MIDI message called a “Program change”
message allows the selection of one of these
sounds. A Program change message consists of a
Channel number, and a program number.
Furthermore, most synthesizers have more than
128 sounds, so MIDI allows for multiple banks – up
to 128.
A sound played by MIDI can be varied after it is
started, just like on many acoustic instruments.
Performance effects such as vibrato can be
applied using a type of message called
“Continuous Controller”, or CC for short. A MIDI CC
message consists of a CC Number, from 0-127,
which identifies the type of change that is to be
made to the sound, then a value from 0 to 127
that determines the amount of the change to the
sound. Types of changes include changes to the
Volume (CC#7) and Pan or Left Right position
(CC#10). Some MIDI CC numbers are specified to
do particular musical functions, others are not. A
list of the MIDI CCs that the PianoBar’s sound
engine responds to is included in Appendix B.
MIDI messages can be recorded by a computer
program called a Sequencer, which records MIDI
data. The MIDI data can be played back into a
MIDI device and will sound like the original
performance. Because MIDI data is a
representation of a musical performance, it is easy
to edit MIDI events in a sequencer, or to display
them as notes on a staff – like sheet music.
Programs such as Sibelius® combine MIDI
recording as well as sophisticated notation
capability in order to aid with composition.
MIDI’s capabilities are vast – and the power of
adding MIDI capability quickly to an acoustic