Yamaha SY85 Owner's Manual page 91

Hi (High note limit)
Range: C-2 ... G8
Controls: [CS2], [CS4], [CS6], [CS8], [-1] [+1], Dial,
[SHIFT]+keyboard
Individually sets the high note limit for each active layer (the highest note
that each layer will produce).
Use the [CS2], [CS4], [CS6], and [CS8] sliders to set the high note limits
of the A, B, C, and D layer voices, respectively. It is also possible to press the
desired note on the keyboard while holding the [SHIFT] key.
See the "Lo" parameter, above, for more details.
PERFORMANCE EDIT MODE /
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