+ (midiInstrument ,string? "Name of the MIDI instrument to use.")
+ (midiMergeUnisons ,boolean? "If true, output only one MIDI note-on
+event when notes with the same pitch, in the same MIDI-file track, overlap.")
+ (midiMaximumVolume ,number? "Analogous to
+@code{midiMinimumVolume}.")
+ (midiMinimumVolume ,number? "Set the minimum loudness for MIDI.
+Ranges from 0 to@tie{}1.")
+ (midiChannelMapping ,symbol? "How to map MIDI channels: per
+@code{staff} (default), @code{instrument} or @code{voice}.")
+ (midiBalance ,number? "Stereo balance for the MIDI channel
+associated with the current context. Ranges from@tie{}@w{-1} to@tie{}1,
+where the values@tie{}@w{-1} (@code{#LEFT}),@tie{}0 (@code{#CENTER})
+and@tie{}1 (@code{#RIGHT}) correspond to leftmost emphasis, center
+balance, and rightmost emphasis, respectively.")
+ (midiPanPosition ,number? "Pan position for the MIDI channel
+associated with the current context. Ranges from@tie{}@w{-1} to@tie{}1,
+where the values@tie{}@w{-1} (@code{#LEFT}),@tie{}0 (@code{#CENTER})
+and@tie{}1 (@code{#RIGHT}) correspond to hard left, center, and hard
+right, respectively.")
+ (midiReverbLevel ,number? "Reverb effect level for the MIDI channel
+associated with the current context. Ranges from 0 to@tie{}1
+(0=off,@tie{}1=full effect).")
+ (midiChorusLevel ,number? "Chorus effect level for the MIDI channel
+associated with the current context. Ranges from 0 to@tie{}1
+(0=off,@tie{}1=full effect).")