IBM ThinkPad 755CX Manual page 261

Advanced Information for Audio Function
simultaneous voices (8 notes at once, each of which can come from
a different instrument). An EXTENDED Multitimbral synthesizer
transmits data on MIDI channels 1–10 and supports 32 simultaneous
voices.
The Mwave feature supplies the following MIDI Mappers for selecting
which MIDI format to use for Mwave:
Mwave EXT GM For Mwave MIDI synthesizer channels 1–10
Mwave Base GM For Mwave MIDI synthesizer channels 13–16
The MPC standard requires authors to provide two versions of every
MIDI composition stored in the same file. Channels 1–10 hold the
version written for Extended Multitimbral synthesizers, whereas
channels 13–16 hold the version written for Base Multitimbral
synthesizers.
Most MIDI files included with Windows applications follow this
standard of containing two versions of each composition. This is
why the Mwave MIDI synthesizer comes with both Base and
Extended MIDI Mapper setups. If all channels were played at once,
both versions of a MIDI composition would play at the same time.
The Mwave Windows synthesizer usually sounds best when the
Mwave EXT GM setup is selected in the MIDI Mapper.
If you have a MIDI file that is not producing sound on your Mwave
feature, MIDI commands may be being sent on a set of channels the
MIDI Mapper is not responding to. Try using the Windows MIDI
Mapper to switch the setup between Mwave Base and Mwave
Extended Multitimbral modes. This lets you see if the MIDI
commands in the file are provided for only one of the two modes.
Other MIDI Controls
The Mwave feature's MIDI synthesizer recognizes several types of
control information in the MIDI data stream:
Key velocity The harder the key is pressed, the louder the note
sounds.
Main volume This is usually controlled by a knob on a MIDI
keyboard. It is received on control number 7.
Pitch bend This can be used to mimic the sound of a whammy
bar on a guitar and is usually controlled by a thumb
wheel on a MIDI keyboard. Note pitch can be varied
2 semitones.
Appendix C. Additional Information for Mwave DSP Features
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