Edirol StudioCanvas SD-20, Руководство пользователя

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About the sound generator modes
About parts and sounds
The SD-20 is able to produce 32 different sounds at once. A sound generator such as the SD-20 that
is able to produce many different sounds simultaneously is called a “
multitimbral sound
module .” “Timbre” refers to the unique characteristics that result in the sound of one instrument
being different from that of another. The ability to simultaneously produce 32 different instrument
sounds means that, using the analogy of an orchestra, you can produce an ensemble consisting of
32 different instrumental parts. On the SD-20, the sound produced by each part is called an
Instrument ( “Instrument list (GM2 / Native mode) ”(p. 247)). You can assign a desired instrument
to each of the 32 parts, creating a 32-part ensemble.
Different types of part
The SD-20 has 32 parts, which are divided into groups A and B. Each group is numbered from 01-
16; i.e., A01-A16 and B01-B16.
Each part can be set either as an
Inst part or a Drum part . Inst parts are used to play melody, bass,
etc. Drum parts are used to play percussion-type sounds. This setting is called the Part Mode .
By default, the following part mode is selected for each part.
When using the MIDI connector to play the SD-20
When using the MIDI connector to play the SD-20, MIDI IN is correlated with Group A.
In other words, the MIDI messages received at MIDI IN will be passed to the Group A parts.
For example, MIDI messages arriving on channel 5 at MIDI IN will sound part 5 of group A (A05)
(at the default settings). When using the MIDI IN connector to play the SD-20, it is not possible to
play the Group B parts.
Polyphony and voices
Each of the SD-20’s sounds consist of units called “
voices
.” There is a limit to the number of voices
that can be used, and the SD-20 is able to use 64 voices simultaneously. Some sounds
(instruments) use more than one voice (
“Instrument list (GM2 / Native mode)
”(p. 247)). The main
reason that an instrument uses some voices is so that velocity can be used to shift between different
sounds, or so that multiple sounds can be layered to create a richer tone.
When you attempt to play more than 64 voices on the SD-20, the most-recently played note will be
given priority, and the oldest of the currently-sounding notes will be turned off one by one. If you
are using only instruments that consist of only one voice, you will be able to play 64 notes
simultaneously. However, if you use instruments that consist of two or four voices, fewer than 64
notes can be played simultaneously. Even if a MIDI note-off message is received, a voice will
continue to be used as long as that note continues to sound. You need to remain aware of this,
particularly when using sounds that have a long release time.
Part mode Corresponding parts
Inst part A01-09, A11-16, B01-09, B11-16
Drum part A10, B10
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