14. MIDI

VA-76 – MIDI in general

14.1 MIDI in general

MIDI connectors

MIDI messages are transmitted and received using three connectors and special MIDI cables:

MIDI IN— This connector receives messages from other MIDI devices.

MIDI OUT— This connector transmits MIDI mes- sages generated on your VA-76

MIDI THRU— This connector “echoes back” all MIDI messages received via MIDI IN

Channels

MIDI can simultaneously transmit and receive mes- sages on 16 channels, so that up to 16 instruments can be controlled. Nowadays, most instruments –like your VA-76– are multitimbral, which means that they can play several musical parts with different sounds.

That concept is not difficult to understand. Just think of your VA-76: it is equipped with an Arranger capable of playing the drums, the bass, and up to six accompa- niment parts, while at the same time allowing you to play up to seven Keyboard parts.

MIDI data types

The most important aspect of the MIDI standard is that it allows one instrument to tell another when to play a note, for how long, and how strongly it should be played.

Other aspects of a musical performance include mod- ulation (vibrato), Pitch Bend (bending), volume, Pan- Pot, etc.

Yet another group of MIDI messages is used to tell the receiver when to select another sound and which sound to select. These messages are called Bank Select, and Program Change. In fact, these are the messages that are automatically recorded at the beginning of each Style division and written to a User Program so that you can recall the Tone selection for all available parts simply by selecting a User Program. Program Change and Bank Select messages also allow you to select User Programs, Styles, and Drum Sets.

Still other MIDI data allow you to synchronize two MIDI instruments so that they start and stop at the same time and run at the same tempo.

MIDI messages used by the VA-76

The way a device responds when it receives MIDI mes- sages (i.e. how it produces sound, etc.) depends on the specifications of that device. If the receiving device is not able to perform the function specified by the incoming message, the musical result will not be what you expected. What it comes down to is this: there are several levels of MIDI compatibility, and not all MIDI compatible instruments understand (i.e. receive) all existing MIDI messages.

Note: MIDI messages for which reception capability is required by the GM system (level 1) are marked by a * sign.

Note messages *— These messages convey notes played on the keyboard. They include the following information:

 

Message

Explanation

 

 

Note number

A number describing the note corresponding

 

 

to the key you pressed or released.

 

 

 

 

 

Note-on

A message signalling that you pressed a key

 

 

(i.e. “start playing now”).

 

 

 

 

 

Note-off

A message signalling that a key was released.

 

 

 

 

 

Velocity

A value describing how strongly you pressed

 

 

a key.

 

 

 

 

On many instruments (such as your VA-76), a note-on message with the velocity value “0” is used to signal the end of a note (i.e. velocity value “0” effectively functions as note-off message).

Pitch Bend *— This message conveys the position of the Bender lever (or pitch bend wheel). The pitch will change when this message is received.

Bank Select (CC00 and CC32), Program Change *—

On the VA-76, these messages are used to select Tones, Styles, and User Programs. By using Bank Select mes- sages (which are in fact control change messages), an even wider variety of memory locations can be selected. Control change messages were added when it became clear that the maximum number of sounds selectable using Program Change messages (128) was no longer sufficient to access all sounds of a given instrument.

Note: Do not forget to send a Program Change message after a Bank Select message because sending only Bank Select messages does nothing whatsoever. The right order for sending these messages is (pay attention to the CPT values):

1.1.0Bank Select CC00 + value

1.1.1Bank Select CC32 + value (0, 1, 2, 3, or 4)

1.1.2Program Change

On the VA-76, CC32 messages are used to select the Tone Map: “0” (don’t leave current Tone Map), “1” (SC-55 mode), “2” (G-800), “3” (G-1000 or EM-2000), or “4” (VA-76).

197

Page 195
Image 195
Roland owner manual Midi in general, Midi messages used by the VA-76