Sound setting only apply to CD mode on optical/coaxial port 44.1/16. Those sound setting doesn’t affect surround 5.1 mode and TV mode.
Treble level
Set speakers treble level, total 15 level of 0.5dB each step.
Subwoofer level
Set subwoofer(s) level, total 15 level of 1dB each step.
Speaker sound timbre
Select speaker sound timbre : Natural, Vivid, Vocal and Comfort
Subwoofer bass
Select pseudo LFE channel bass effect : Off, Soft, Comfort, Strong
Upsampling filter
Select upsampling interpolation filter 44.1KHz to 96KHz :
Constant, Poly-Phase, Linear, Cubic