The China Conservatory of Music is the most authoritative piano grading institution.

Piano

The piano is a keyboard instrument invented by Italian Bartolomeo Cristofori (1655-1731) in 1709.

Pianos are composed of keys (including white keys and black keys) and metal string soundboards. Generally, the sound range of an 88-key piano ranges from 27.5Hz to 4186.01Hz, and the range of a 108-key piano reaches up to 7902.13Hz, which almost covers all musical sounds. All the sounds in the system are one of the instruments with the widest range and are widely used for solos, ensembles and accompaniments.

The piano case is the most intuitive component of the piano. As the outer shell of the piano, it can support and protect the internal devices, as well as be beautiful. The piano 70 is made of wood. The durability and sturdiness of the piano casing wood are the key to measuring the quality of the piano casing.

The casing of high-quality pianos is made of pure solid wood. Natural solid wood has strong bearing capacity, is not easy to age or crack, and can be stored longer. Therefore, pianos made of natural solid wood have a longer service life.

Knowledge expansion:

The bracket is the central frame of the piano and the final sounding board of the piano. It is mainly made of cast iron, with clear outline, smooth surface and stable quality. Because it needs to carry the tension of all the strings, the cast iron bracket looks huge and has extremely high endurance.

The frame of a grand piano weighs more than 1/3 of the total weight and carries about 20 tons of tension from all the strings. The frame structure of an upright piano is usually a rectangular structure, carrying about 15 tons of tension for all strings.

The tuning nail is a nail-shaped bolt that can be twisted and rotated with a special wrench, which is used to fasten the strings to the bracket. The turning machine of the tuning pins is made of special high-carbon steel with a lock, which allows the strings to be firmly wound around the pegs and keeps the intonation stable for a long time under the high-strength tension of the strings.

The strings are the core part of the sound production of the piano. The strings are arranged and stretched on the bracket to form a string array. A typical piano has about 220 strings, and the number of strings varies among different brands of pianos.

The strings are divided into three groups: treble area, alto area, and bass area. There are 3 strings for each note in the treble area, 2 strings for each note in the alto area, and 1 string for each note in the bass area. Three strings of one note are called a unison string set, that is, the three strings are tuned to the same pitch (frequency) to increase the volume and improve the timbre.