Sony 4-127-580-13(1) Operating Instructions Manual page 62

When you are using the built-in speaker,
the Noise Cut function does not work.
During playback set the NOISE CUT
switch to "ON."
High
frequency
sound
Frequency
Low
frequency
sound
62
GB
High frequency
noise such as
an electronic
device
You can hear
the human
voice more
clearly.
Low frequency
noise such as
roaring noise
from wind

Notes
The bass sound cannot be reinforced if the

NOISE CUT switch is set to "ON. "
The effect of the Noise Cut function may be

different depending on the condition of the
recorded voice.
To cancel the Noise Cut function
Set the NOISE CUT switch to "OFF. "