Standing waves on a guitar
Time-averaged interference holograms showing two-dimensional flexural standing waves on the front plate of a guitar. The interference patterns, which indicate contours of equal-amplitude vibrations, are much more symmetrical than those observed for the violin. The contours in a violin cross the edges of the instrument in other words, the sides of a violin transfer significant vibrations from the front to the back. Unfortunately, it is not easy to obtain similar high-quality interference patterns for a violin, which has smaller, more curved and less reflective surfaces.