Modes of Vibration Caught on Camera

In the previous animation you have seen how a plucked guitar string will vibrate at numerous "modes of vibrarion" at once, and therefore produce sound at many harmonically related frequencies ("overtones"). Just to show that these modes of vibration are real, here a little youtube video by nicogetz, where he placed a camera phone inside his guitar and then played a tune. The camera phone is too slow to pick out all the details of the motion of the strings (the phone will collect somewhere around 40 to 70 frames a second, while the highest harmonics of the motion of the strings may vibrate at several thousand frames a second) but the result is that only some of the modes of vibration will be "aliased" by the video to become visible to the naked eye. Nevertheless a beautiful illustration to show that modes of vibration are a feature of sound sources.