Using Volumio to create a led va meter

Hello all,

I just set up my first Volumio and created some python scripts (get the current song name …). Thats just works fine.
But I stuggeling to get a va-meter runniung at command line. For now I just wanna get the current db of the left and right channel to set up a led va meter later.

Hase anyone some experience with this task? I just need the scripts to extract the current db values from both channels (left and right). The hardware build might be the easy part.