A tuning fork is a tool used to provide a pure tone. It is used as a reference for accurate pitch, and to mark time in quartz digital watches. Hearing tests may employ a thi tool, as may physics classes focusing on the study of sound.
In appearance, a tuning fork is a two-pronged metal fork that is shaped like a U and extends from a handle. Most people are familiar with the fundamental mode of this device, which is the long-lasting mode used as a standard for pitch. The so-called “clang” mode is a higher frequency and dies away very quickly.
Invented in 1711 by musician John Shore, and originally called the “pitch-fork,” the tuning fork was further developed by several inventors with an eye to providing a new type of musical instrument. This idea never caught on, however. Today, it does have a musical use, however: it can be used to set the pitch for performers or instruments.
For example, a tuning fork may be used by a conductor or performer to set an accurate pitch for a musical performance of an a cappella group. Often, one pitch is struck and the conductor or the various vocal parts figure out their pitch based on the struck pitch. If the piece has several movements, pitches may be given before the start of each new section.
There are other musical uses as well. A set of tuning forks, or one for middle C and a good ear, can be used to tune a piano, although electronic tuners have become popular. Timpanists use a pitch pipe or a set of forks to tune the timpani. For musical purposes, these tools are readily available at pitch A-440, as well as middle C, and sets are available for the notes of the C major scale as well as the chromatic scale.
For medical purposes, such as testing for hearing loss, there are specialized tuning forks with the pitches needed for various, specific testing protocols. The scientific version of this tool is a specialized device for research in acoustics and sound wave analysis and for calibrating various devices. These different types of tuning forks are not interchangeable. For example, scientific tuning forks are usually mounted, whereas musical ones are handheld.