Yamaha MONTAGE M6 Operation Manual page 377

Settings: 0–127
The larger the value, the longer it takes for the LFO effect to reach the maximum.
0: LFO changes to the maximum value without any fade-in.
Hold (LFO Hold Time)
Sets the time for maintaining the LFO effect after the maximum level has been reached.
Settings: 0–126, Hold
Hold: Does not fade out
Low value: Fast fade-in
High value: Slow fade-in
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