How to adjust the attenuation value corresponding to the sound curve volume scale?

Which system do you use? Android, Ubuntu, OOWOW or others?

Android

Which version of system do you use? Khadas official images, self built images, or others?

self built images

Please describe your issue below:

problem:

audio_policy_volumes.xml   //Sound Curve Profile

I want to adjust the sound curve to better control the sound. Can you tell me how to adjust the attenuation value corresponding to the volume scale value?