Modern tuning forks were invented in 1711 by a British musician John Shore, Sergeant Trumpeter to the court, who had parts specifically written for him by both George Frideric Handel and Henry Purcell.

 

How are tuning forks constructed?

The main reason for using the fork shape is that it produces a very pure tone, with most of the vibrational energy at the fundamental frequency, and little at the overtones (harmonics), as is the case with other resonators. The reason for this is that the frequency of the first overtone is about 5²/2² = 25/4 = 6 1/4 times the fundamental (about 2 1/2 octaves above it) By comparison, the first overtone of a vibrating string is only one octave above the fundamental. So when the fork is struck, little of the energy goes into the overtone modes; they also die out correspondingly faster, leaving the fundamental. It is easier to tune other instruments with this pure tone.

Another reason for using the fork shape is that, when it vibrates in its principal mode, the handle vibrates up and down as the prongs move apart and together. There is a node (point of no vibration) at the base of each prong. The handle motion is small, allowing the fork to be held by the handle without damping the vibration, but it allows the handle to transmit the vibration to a resonator (like the hollow rectangular box often used), which amplifies the sound of the fork.

Without the resonator (which may be as simple as a table top to which the handle is pressed), the sound is very faint. The reason for this is that the sound waves produced by each fork prong are 180° out of phase with the other, so at a distance from the fork they interfere and largely cancel each other out. If a sound absorbing sheet is slid in between the prongs of a vibrating fork, reducing the waves reaching the ear from one prong, the volume heard will actually increase, due to a reduction of this cancellation.

Tuning forks themselves can be tuned by filing material off the prongs. Filing the ends of the prongs raises the pitch, while filing the inside of the base of the prongs lowers it.

What are tuning forks used for?

Many alternative/holistic healers and practioners use tuning forks in their work and dedication to the enhancement of humans, animals, plants and the environment.  Before industrial noise pollution, the OM, eternal sound of the universe was heard and understood by all living and non-living universal participants.

http://en.wikipedia.org/wiki/Tuning_fork

 

Return to tuning forks home page.

 
L Michaels Jewelry Designs --  AMERICAN MADE magnetic jewelry for every budget, need and size.