Yamaha DVX-S120 Owner's Manual page 74

You can control the big sound effects and focus on
listening clearly to speech. Enjoy a DSP Program even in
the evening at a low volume
NIGHT--
4JJi! ¸ _ i
_ii_iii _i_ ! _i_
AMP
To return to normal play
Press NIGHT to deactivate Night Listening mode, "Night L.
OFF appears in the CinemaStation Display.
-- DSP Program
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