2013 Toyota Tundra CrewMax Owners Manual - Page 326

3-2. Using the audio system Type B and C Turning Mode displayed BASS MID TREB FADE adjusts the level. Sound quality mode Bass* Mid-range* (type B only) Treble* Front/rear volume balance Left/right volume balance Turn to the left Turn to the right Level -5 to 5 -5 to 5 -5 to 5 F7 to R7 Low High Shifts to rear Shifts to front BAL L7 to R7 Shifts to left Shifts to right *:The sound quality level is adjusted individually in each audio mode.