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28-471: The Goldene Stimmgabel (English: Golden Tuning Fork ) was an annual prize awarded within the German music scene from 1981 to 2007. The prizes were awarded according to the number of records sold from October of the previous year to June of the year of the award, as determined by Media Control . It was established in 1981 by Dieter Thomas Heck , who hosted the television gala award show every year since then. It

56-452: A /12 if the prongs have rectangular cross-section of width a along the direction of motion. Tuning forks have traditionally been used to tune musical instruments , though electronic tuners have largely replaced them. Forks can be driven electrically by placing electronic oscillator -driven electromagnets close to the prongs. A number of keyboard musical instruments use principles similar to tuning forks. The most popular of these

84-654: A 360- hertz steel tuning fork as its timekeeper, powered by electromagnets attached to a battery-powered transistor oscillator circuit. The fork provided greater accuracy than conventional balance wheel watches. The humming sound of the tuning fork was audible when the watch was held to the ear. Alternatives to the common A=440 standard include philosophical or scientific pitch with standard pitch of C=512. According to Rayleigh , physicists and acoustic instrument makers used this pitch. The tuning fork John Shore gave to George Frideric Handel produces C=512. Tuning forks, usually C512, are used by medical practitioners to assess

112-463: A frequency of 32,768 Hz in the ultrasonic range (above the range of human hearing). It is made to vibrate by small oscillating voltages applied by an electronic oscillator circuit to metal electrodes plated on the surface of the crystal. Quartz is piezoelectric , so the voltage causes the tines to bend rapidly back and forth. The Accutron , an electromechanical watch developed by Max Hetzel and manufactured by Bulova beginning in 1960, used

140-449: A patient's hearing. This is most commonly done with two exams called the Weber test and Rinne test , respectively. Lower-pitched ones, usually at C128, are also used to check vibration sense as part of the examination of the peripheral nervous system. Orthopedic surgeons have explored using a tuning fork (lowest frequency C=128) to assess injuries where bone fracture is suspected. They hold

168-464: A piezoelectric device. Upon coming in contact with solids, amplitude of oscillation goes down, the same is used as a switching parameter for detecting point level for solids. For liquids, the resonant frequency of tuning fork changes upon coming in contact with the liquids, change in frequency is used to detect level. Rinne test A Rinne test should always be accompanied by a Weber test to also detect sensorineural hearing loss and thus confirm

196-465: A real fracture while wondering if a response means a sprain. A systematic review published in 2014 in BMJ Open suggests that this technique is not reliable or accurate enough for clinical use. Tuning forks also play a role in several alternative therapy practices, such as sonopuncture and polarity therapy . A radar gun that measures the speed of cars or a ball in sports is usually calibrated with

224-420: A relatively low pressure (thus low acoustic impedance). The pitch of a tuning fork can also be heard directly through bone conduction , by pressing the tuning fork against the bone just behind the ear, or even by holding the stem of the fork in one's teeth, conveniently leaving both hands free. Bone conduction using a tuning fork is specifically used in the Weber and Rinne tests for hearing in order to bypass

252-597: A replacement for formal audiometry . Recently, its value as a screening test has been questioned. The Rinne test is not reliable in distinguishing sensorineural and conductive loss cases of severe unilateral or total sensorineural loss. In such cases, bone conduction to the contralateral normal ear will be better than air conduction, resulting in a false negative. In such a case, the Weber test will, however, show signs of lateralization, implying some kind of pathology. Formal audiometry testing would be required if any abnormal result

280-436: A standard temperature. The standard temperature is now 20 °C (68 °F), but 15 °C (59 °F) is an older standard. The pitch of other instruments is also subject to variation with temperature change. The frequency of a tuning fork depends on its dimensions and what it is made from: where The ratio I / A in the equation above can be rewritten as r /4 if the prongs are cylindrical with radius r , and

308-445: A tuning fork. Instead of the frequency, these forks are labeled with the calibration speed and radar band (e.g., X-band or K-band) they are calibrated for. Doubled and H-type tuning forks are used for tactical-grade Vibrating Structure Gyroscopes and various types of microelectromechanical systems . Tuning fork forms the sensing part of vibrating point level sensors . The tuning fork is kept vibrating at its resonant frequency by

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336-413: Is because its principal mode of vibration is symmetric, with the two prongs always moving in opposite directions, so that at the base where the two prongs meet there is a node (point of no vibratory motion) which can therefore be handled without removing energy from the oscillation (damping). However, there is still a tiny motion induced in the handle in its longitudinal direction (thus at right angles to

364-451: Is better than bone conduction. Thus, a "positive" result indicates the healthy state, in contrast to many other medical tests. Therefore, some prefer to avoid using the terms "positive" or "negative", and simply state if the test was normal or abnormal. For example: "Rinne's test was abnormal in the right ear, with bone conduction greater than air conduction". This test and its complement, the Weber test , are quick screening tests and are not

392-428: Is reduced, just as a loudspeaker requires a baffle in order to radiate efficiently. Commercial tuning forks are tuned to the correct pitch at the factory, and the pitch and frequency in hertz is stamped on them. They can be retuned 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. Currently, the most common tuning fork sounds

420-401: Is that the frequency of the first overtone is about ⁠ 5 / 2 ⁠ = ⁠ 25 / 4 ⁠ = 6 + 1 ⁄ 4 times the fundamental (about 2 + 1 ⁄ 2 octaves above it). By comparison, the first overtone of a vibrating string or metal bar is one octave above (twice) the fundamental, so when the string is plucked or the bar is struck, its vibrations tend to mix

448-469: Is the Rhodes piano , in which hammers hit metal tines that vibrate in the magnetic field of a pickup , creating a signal that drives electric amplification. The earlier, un-amplified dulcitone , which used tuning forks directly, suffered from low volume. The quartz crystal that serves as the timekeeping element in modern quartz clocks and watches is in the form of a tiny tuning fork. It usually vibrates at

476-399: The inner ear albeit at a reduced volume, or via the bones of the skull to the opposite ear. Note that the words positive and negative are used in a somewhat confusing fashion here, as compared to their typical use in medical tests . Positive or negative in this case means that a certain parameter that was evaluated was present or not. In this case, that parameter is whether air conduction

504-449: The middle ear . If just held in open air, the sound of a tuning fork is very faint due to the acoustic impedance mismatch between the steel and air. Moreover, since the feeble sound waves emanating from each prong are 180° out of phase , those two opposite waves interfere , largely cancelling each other. Thus when a solid sheet is slid in between the prongs of a vibrating fork, the apparent volume actually increases , as this cancellation

532-486: The end of the vibrating fork on the skin above the suspected fracture, progressively closer to the suspected fracture. If there is a fracture, the periosteum of the bone vibrates and fires nociceptors (pain receptors), causing a local sharp pain. This can indicate a fracture, which the practitioner refers for medical X-ray. The sharp pain of a local sprain can give a false positive. Established practice, however, requires an X-ray regardless, because it's better than missing

560-479: The form of a two-pronged fork with the prongs ( tines ) formed from a U-shaped bar of elastic metal (usually steel ). It resonates at a specific constant pitch when set vibrating by striking it against a surface or with an object, and emits a pure musical tone once the high overtones fade out. A tuning fork's pitch depends on the length and mass of the two prongs. They are traditional sources of standard pitch for tuning musical instruments. The tuning fork

588-403: The fundamental and overtone frequencies. When the tuning fork is struck, little of the energy goes into the overtone modes; they also die out correspondingly faster, leaving a pure sine wave at the fundamental frequency. It is easier to tune other instruments with this pure tone. Another reason for using the fork shape is that it can then be held at the base without damping the oscillation. That

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616-415: The nature of hearing loss. The Rinne test was named after German otologist Heinrich Adolf Rinne (1819–1868); the Weber test was named after Ernst Heinrich Weber (1795–1878). The Rinne test is performed by placing a 512 Hz vibrating tuning fork against the patient's mastoid bone and asking the patient to tell you when the sound is no longer heard. Once the patient signals they can't hear it,

644-427: The note of A = 440 Hz , the standard concert pitch that many orchestras use. That A is the pitch of the violin's second-highest string, the highest string of the viola, and an octave above the highest string of the cello. Orchestras between 1750 and 1820 mostly used A = 423.5 Hz, though there were many forks and many slightly different pitches. Standard tuning forks are available that vibrate at all

672-430: The oscillation of the prongs) which can be made audible using any sort of sound board . Thus by pressing the tuning fork's base against a sound board such as a wooden box, table top, or bridge of a musical instrument, this small motion, but which is at a high acoustic pressure (thus a very high acoustic impedance ), is partly converted into audible sound in air which involves a much greater motion ( particle velocity ) at

700-487: The pitches within the central octave of the piano, and also other pitches. Tuning fork pitch varies slightly with temperature, due mainly to a slight decrease in the modulus of elasticity of steel with increasing temperature. A change in frequency of 48 parts per million per °F (86 ppm per °C) is typical for a steel tuning fork. The frequency decreases (becomes flat ) with increasing temperature. Tuning forks are manufactured to have their correct pitch at

728-428: The still vibrating tuning fork is then placed 1–2 cm from the auditory canal. The patient is then asked again to indicate when they are no longer able to hear the tuning fork. Air conduction uses the apparatus of the middle ear ( pinna , eardrum and ossicles ) to amplify and direct the sound to the cochlea , whereas bone conduction bypasses some or all of these and allows the sound to be transmitted directly to

756-400: Was broadcast on either ARD or ZDF until the year 2000. From 2001 to 2007 the award show was broadcast by ZDF alone. In 2008, ZDF decided not to present the award and did not announce whether they would be resumed later, discontinued, or replaced with another award. The award has not been held since (as of October 2019). Tuning fork A tuning fork is an acoustic resonator in

784-425: Was invented in 1711 by British musician John Shore , sergeant trumpeter and lutenist to the royal court. A tuning fork is a fork-shaped acoustic resonator used in many applications to produce a fixed tone. The main reason for using the fork shape is that, unlike many other types of resonators, it produces a very pure tone , with most of the vibrational energy at the fundamental frequency . The reason for this

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