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Tuning of a grand piano
The piano requires various forms of maintenance to produce its best sound. Maintenance is also important for the appearance of the piano.
Care by Technician
Tuning
Main article: Piano tuning
Pianos that are prized by their owners are tuned regularly, usually once every six months for domestic pianos, and always just before a performance in concert halls. The longer a piano is left out of tune, the more time and effort it will take for a technician to restore it to correct pitch. When a piano is only slightly out of tune, it loses the glowing tonal quality characteristic of a freshly tuned piano, probably because strings slightly out of tune with one another have weaker sympathetic vibrations. Pianos that are more than slightly out of tune tend to be unpleasant to play and listen to, to an extent that varies with the ear of the listener. A tuning hammer is the main tool that piano technicians use.
Pianos go out of tune primarily because of changes in humidity. Tuning can be made more stable by installing special equipment to regulate humidity, inside or underneath the piano. There is no evidence that being out-of-tune permanently harms the piano itself. However, a long-term low-humidity environment may eventually crack the soundboard and warp keys and other wooden parts. In particular, pianos located in arid climates and otherwise very dry rooms (for example, a cold climate with an extended heating season) require special attention to humidity control.
There are a growing number of musicians and composers who are tuning the piano to non-standard tunings, in order to achieve different kinds of harmony not possible with the standard 12-tone equal temperament tuning (normally found on the piano). Examples of such persons are La Monte Young, Terry Riley, and Michael Harrison - to name a few. Their tunings create never before heard of combinations of intervals (some large and some "micro") that lend themselves to many beautiful and interesting new harmonies, scales, and textural effects not possible in equal temperament. Of course, these brands of tuning are limited by the internal structure of the instrument itself. One must be very careful because the piano can only hold so much tension before it breaks.
A piano tuner at work.
Voicing
The felt hammers of the piano tend to harden over time. They also form grooves at the points of contact with the strings. Harder hammers produce a brighter tone quality, which may ultimately become harsh and undesirable. Piano technicians can soften hammers using special tools called voicing needles. They also sometimes use special hardening agents when the hammers are too soft (though this practice is controversial among some technicians). In either case, an important goal is uniform tone quality across the piano, since the hammers are not used with equal frequency and therefore tend to wear unevenly. How much and how forcefully the piano is played is a factor in how often a piano is voiced, as are the piano's setting and the preferences of its players.
Over time, the strings will wear grooves into the surface of the hammers. The grooves eventually become deep enough, and the head of the hammer flattened enough, that voicing cannot restore the piano's tone. At this point, a technician can file the hammers, restoring their original ovoid shape and pristine surface at the expense of making them somewhat smaller. This process may repeat several times, until there is not enough felt left on the hammers for another filing, and they must be replaced.
Regulation
Over time, the performance of a piano action tends to decline, due to the compression of felt, warping of wood, and other types of wear. A skilled technician can restore it to optimal precision, in a process called regulation, which involves adjustments ranging from turning a small screw to sanding down a wood surface. Many new pianos are not perfectly regulated when released from the factory, or quickly lose their regulation when moved to their new home, and benefit from regulation in the store or in the home.
The goal of regulation is to make the piano's touch and sound consistent across all notes, allow it to comfortably achieve the widest possible range of dynamics, and make the keys responsive to even the most rapid or most subtle motions of the player.
There are many dozens of types of regulation a piano may require. The most important include adjustment of:
Let-off, the point when the hammer disengages from the jack and flies freely. If the let-off is...(and so on) To get More information , you can visit some products about , . The Sports Metal Sunglasses with Revo Coated Lenses products should be show more here!
