bar = Instance.new("Part",script)
bar.Size = Vector3.new(0,10,0)
bar.Anchored = true

local sound = Instance.new("Sound", script)
sound.SoundId = "rbxassetid://301964312"
sound.Looped = true
sound:Play()

local maxLoudness = 30

while true do
print(sound.PlaybackLoudness)
    bar.Position = Vector3.new(1,sound.PlaybackLoudness/10,1)
    wait(0.05)
end