MIDI SUPPLEMENT
© 1985, 1986, 1987 E-mu Systems, Inc. Page 209
How does MIDI differentiate between different MIDI instruments?
MIDI provides 16 independent channels of information suitable for driving up to 16 polyphonic
synthesizers or other MIDI devices.
There are three modes that determine how each MIDI instrument responds to these channels.
In Omni mode, the Emulator II (or any other MIDI keyboard) listens to all channels at once. No
matter how many notes from how many sources make it through the MIDI bus into the
instrument, when in Omni mode it will attempt to play all of them.
In Poly mode, the instrument can “tune in” to one MIDI channel --just like you can tune in one
channel of your television. Having a bunch of instruments set to Poly mode lets you send
specific information to different instruments from the Emulator II’s Sequencer over different MIDI
channels.
Mono mode is considered a “multi-timbral” mode. In mono mode, each individual analog
synthesizer voice can be driven by one specific MIDI channel of information to play a certain
melodic line. Each voice can also have its own “patch” (program), so an analog synthesizer
capable of MIDI Mono mode can therefore produce multiple timbres simultaneously. Since the
Emulator II does not have an equivalent to the analog synthesizer voice, the Emulator II does
technically not support Mono mode. However, each Preset can be assigned to receive
information through a separate MIDI channel, which provides Mono-like operation but unlike
traditional MIDI Mono operation, each Preset can respond polyphonically. Of course, you still
cannot play more than eight notes on the Emulator II regardless of what MIDI mode you select.
16 channels, huh? Sounds like a lot of patch cords to me!
MIDI information is transmitted serially, meaning that all data is sent in sequence. As a result, a
single line can carry the MIDI information for all 16 channels, with each instrument monitoring all
the words that pass over the MIDI interface but responding only to the data on its particular
channel. Typically, MIDI instruments include a MIDI IN, MIDI OUT, and MIDI THRU jack. The
instrument receives data over the MIDI IN jack and transmits data over the MIDI OUT jack; the
MIDI THRU jack provides a replica of the signal at the MIDI IN jack. Therefore, if you want to
slave three keyboards to a master keyboard, you would patch the MIDI OUT from the master
keyboard to the MIDI IN of the first slave, patch MIDI THRU from the first slave to the MIDI IN of
the second slave, and connect MIDI THRU from the second slave to MIDI IN of the third slave.
What kind of words does the MIDI language include?
Spoken language is a collection of words that convey a particular set of meanings, hopefully
understood by all those who speak the language. As soon as we start talking about a musical
language, the first question is: What concepts do we want this language to define? Since
musical instruments will be doing the talking, the language should consist of musical terms --
pitch, tempo, and so
on. In fact, let’s set up a practical example and see what words our language would need.
Suppose we have two synthesizers, Synth A and Synth B, and want Synth B to precisely follow
along with what is being played on Synth A to create a “doubling” effect. To do this, our
“language” would have to convey several things.
Содержание EII+
Страница 11: ...INTRODUCTION 1985 1986 1987 E mu Systems Inc Page 11 INTRODUCTION ...
Страница 20: ...INTRODUCTION 1985 1986 1987 E mu Systems Inc Page 20 ...
Страница 26: ...THE GUIDED TOURS 1985 1986 1987 E mu Systems Inc Page 26 THE GUIDED TOURS ...
Страница 84: ...VOICE DEFINITION MODULE 1985 1986 1987 E mu Systems Inc Page 84 Fig VDEF 8 Fig VDEF 9 ...
Страница 118: ...PRESET DEFINITION MODULE 1985 1986 1987 E mu Systems Inc Page 118 ...
Страница 168: ...ENTER MODULE 1985 1986 1987 E mu Systems Inc Page 168 ENTER MODULE ...
Страница 170: ...SEQUENCER MODULE 1985 1986 1987 E mu Systems Inc Page 170 SEQUENCER MODULE BACKGROUND EXT CLOCK SETUP EDIT ...
Страница 214: ...SMPTE SUPPLEMENT 1985 1986 1987 E mu Systems Inc Page 214 SMPTE SUPPLEMENT OVERVIEW PROTOCOL ...