Yamaha MU90R Owner's Manual page 78

Pitch Bend Control (PitBndCtrl)
Selected Part and MIDI channel
This determines the Pitch Bend range for the Part's Voice. (Pitch Bend
is usually controlled by a pitch bend wheel on a MIDI keyboard.)
Modulation Wheel — LFO Pitch Modulation Depth
(MW LFOPMod)
Selected Part and MIDI channel
This determines how widely the pitch is modulated by the LFO (low
frequency oscillator). This is generally controlled from a modulation
wheel on a MIDI keyboard and produces a vibrato effect. The
higher the value, the deeper the pitch modulation, and hence, the
more pronounced the vibrato effect.
Graphically shows Pitch Bend Control setting for each Part.
Graphically shows LFO Pitch Modulation Depth setting for each Part.
MULTI MODE
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