Table of Contents
When an object vibrates due to a generating force there are a number of ways that the motion of the vibration can pass through the material. Here is a list of the various ways a material can vibrate. This page is eventually planned to have visual examples of the ways the vibrations propagate through the materials as well as breakdowns to the relevant modes.
Transverse Vibration
The most common form of vibration in string instruments, occurs when a string is plucked, struck, or bowed. This is also the primary form of vibration on drums and bar percussion instruments.
Lateral Vibration
A perpendicular vibration pattern to that found on Transverse Vibration, this pattern typically vibrates perpendicular to the shortest end of a vibrating object and is difficult to maintain and will often decay to transverse vibration or torsional vibration.
Longitudinal Vibration
Fundamental behavior of such instruments as the Long-String Instrument and Cristal Baschet, rarely the playing technique on string instruments or lamellophones also sometimes used on metal and glass tines. Paradoxically this is also the primary way sound vibrates inside of tubular wind instruments in the form of standing waves.
Torsional Vibration
A pattern of vibration defined by the circular rotation of an object, with both vibrating sides rotating counter to one another.
Here is a visual example of torsional vibration of a free bar drawn by Jeff La Favre1)
Radial Vibration
A vibration pattern displayed by the expansion and contraction of an object.