Sound-responsive structure's movement

Hi guys,

I am fairly new to grasshopper and firefly. Our design project is a sound responsive "arm" (structure) that rotates (moves) with different ranges of sound frequency produced by a piano. Each component is being formed of 6 sections that rotate in relation to their either side components, exept the first section (as shown in rhino file).We have simplified the frequency range into 3 categories. How can I make the arm rotate when the specific frequency is the output of the frequency spectrum component of firefly?

Please find attached the Rhino and .ghx files of the project.

ARM%201.gh

Arm%20Radius%20Circles%201.3dm