Noteblock sound

Have noteblocks be able to make a sound constantly until you flip the lever off, basically the function of a redstone lamp, but it's a noteblock. I want to be able to have it play a sound longer than normal, I think it would be cool to have. Instead of: *Pull lever "Bum." It would be: *Pull lever "Buuuuuuuuuuuuuuuu...." *Push lever back "uuum". It's only a thought, not a requirement. I just think it could be better in some ways.