How do I script a songs beat to a brick to?

You can probably set up timing. Something like this:

local brick = script.Parent


function brickChange(time)
    wait (time)
    brick.BrickColor -- whatever the parameter is (brick color name whatever)
end


while true do
    brickChange() -- insert time inside there
end

this might not work, but you have to just tweak it. I don't think there is a way to detect bass in a song inside of Roblox.