Lexus LS460 Owners Book page 463

"DSP" tab
The sound quality level is adjusted individually
■
The treble, mid and bass levels can be adjusted for the each audio mode separately.
About Automatic Sound Levelizer (ASL)
■
ASL automatically adjusts the volume and tone quality according to the vehicle
speed, wind noise or other noise.
3-3. Using the audio system
Surround on/off (with DVD
player)
Automatic Sound Levelizer
(ASL) on/off
3
461