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MIDI
What is MIDI?
8. MIDI

WHAT IS MIDI?

Here is a brief overview of MIDI, as related to the Pa50SD. If
interested, you may find more information on the general use
of MIDI in the various specialized magazines and books.

In general

MIDI stands for Musical Instruments Digital Interface. This
interface lets you connect two musical instruments, or a
computer and various musical instruments.
Physically, MIDI is composed of three different connectors.
The MIDI IN receives data from another device; the MIDI
OUT sends data to another device; the MIDI THRU sends to
another device exactly what was received on the MIDI IN
(this is useful to daisy-chain more instruments).

Channels and messages

Basically, a MIDI cable transmits 16 channels of data. Think
to each MIDI channel as a TV channel: the receiver must be
set on the same channel of the transmitter. The same happens
with MIDI messages: when you send a Note On message on
channel 1, it will be received on channel 1 only. This allows
for multitimbricity: you can have more than one sound play-
ing on the same MIDI instrument.
There are various messages, but here are the most commonly
used:
Note On – This message instructs an instrument to play a
note on a specific channel. Notes have both a name (C4
standing for the center C) and a number (60 being the equiv-
alent for C4). A Note Off message is often used to say the note
has been released. In some case, a Note On with value “0” is
used instead.
Together with the Note On message, a Velocity value is always
sent. This value tells the instrument how loud the note must
play.
Pitch Bend (PB) – You can generate this message acting on
the joystick (X movement). The pitch is translated up or
down.
Program Change (PC)– When you select a Program, a Pro-
gram Change message is generated on the channel. Use this
message, together with Control Change 00 and 32, to
remotely select Pa50SD data from a sequencer or a master
keyboard.
Control Change (CC) – This is a wide array of messages,
controlling most of the instrument parameters. Some exam-
ples:
CC00, or Bank Select MSB, and CC32, or Bank Select
LSB. This message pair is used, together with the Pro-
gram Change message, to select a Program.
CC01, or Modulation. This is the equivalent of pressing
up the joystick. A vibrato effect is usually triggered on.
CC07, or Master Volume. Use this controller to set the
channel’s volume.
CC10, or Pan. This one sets the channel’s position on
the stereo front.
CC64, or Damper Pedal. Use this controller to simulate
the Damper pedal.

Tempo

Tempo is a global MIDI message, that is not tied to a particu-
lar channel. Each Song includes Tempo data.

Lyrics

Lyrics are non-standard MIDI events, made to display text
together with the music. Pa50SD can read many of the avail-
able Lyrics format on the market.

MIDIFILES

Midifiles, or Standard MIDI Files (SMF), are a practical way
of exchanging songs between different instruments and com-
puters. Pa50SD has the SMF format as its default song for-
mat, so reading a song from a computer, or saving a song that
a computer software can read, is not a problem at all.
Pa50SD sequencers are compatible with the SMF in format 0
(all data in one track; it is the most common format) and 1
(multitrack). It can read the SMF in Song Play mode and
modify/save them in Song mode. It can save a Song in SMF 0
format in the Backing Sequence or Song mode.
When in Song Play mode, the Pa50SD can also display SMF
lyrics in Solton, M-Live (Midisoft), Tune1000 and compati-
ble (Edirol, GMX, HitBit, XF) formats, and the chord abbre-
viations of SMF in Solton, M-live (Midisoft), GMX, and XF
format.

THE GENERAL MIDI STANDARD

Some years ago, the musical instruments world felt a need for
some further standardization. Then, the General MIDI Stan-
dard (GM) was born. This extension of the basic MIDI sets
new rules for compatibility between instruments:
A minimum of 16 MIDI channels was required.
A basic set of 128 Programs, correctly ordered, was
mandatory.
The Drum Kit had a standard order.
Channel 10 had to be devoted to the Drum Kit.
A most recent extension is the GM2, that further expands the
Programs database. The Pa50SD is soundwise-compatible
with the GM2 standard.

THE GLOBAL CHANNEL

Any channels with the Global option assigned (see “Page 6 -
MIDI IN Channels” on page 127) can simulate the Pa50SD
integrated keyboard. When the Pa50SD is connected to a
master keyboard, transmission should take place over the
Global channel of the Pa50SD.
The MIDI messages received over a Global channel and not
over a standard channel are affected by the buttons of the
KEYBOARD MODE section, as well from the split point.
Therefore, if the SPLIT button LED is lit up, the notes that
arrive to the Pa50SD over this channel will be divided by the