Sony NT-2 - Manual (Page 21)

21
-EN
Playback
Protecting your hearing (AVLS)
The AVLS (Automatic Volume Limiter System) function allows you to limit
the maximum volume of the recorder to protect your ears.
Slide AVLS on the remote controller to ON.
The volume does not exceed over “P 23” (maximum “P 30”) when using
AVLS function, even if you attempt to turn the volume up higher.