Major Factors Determining the Tone, Volume and Scale Strings

• When the hammer strikes the strings, the strings vibrate at a fixed frequency. This is the source of the piano's sound.
• The piano strings are very intimately related with the final quality of the piano's sound on all counts-the tone, volume and scale.
• The ends of the string are wrapped around the tuning and hitch pins. The strings are then tightly stretched. Of the overall string length, the area between the bearings and the bridge which actually vibrates when the hammer strikes the piano string, it is called the effective string length.
• The section of the piano string between the bearings and the pressure bar is called the resonance string. In order to create a beautiful piano tone, the length of the resonance string should be in strict numerical ratio to the effective string length.
• The strings for the higher pitches are thing and short. As the pitch lowers, the strings progressively thicken and lengthen. To further thicken (increase the mass of the piano strings) for the lower registers, copper wire is wrapped around the music wire core.



Materials

• The music wires are made from high purity carbon steel. This is the best material for producing the finest piano tone. This material is extremely strong tensionally and torsionally, does not bend easily, and easily withstands the impact of the hammer striking the strings.
• The quality of the music wire is determined by the material, the concentricity (how close the cross section is to a perfect circle), the tensile strength, the resistance to breakage, and the surface finish.
• Yamaha's music wire is produced by an outside factory. However, Yamaha places stringent demands on the standards concerning the design, materials and production quality. Therefore the music wire is produced for Yamaha under optimal conditions.
• Strict torsion, corrosion, deformation and string impact tests are carried out to impose stringent quality standards.

Design

• The design of the stringing scale requires much skill, and meticulous care. The tone is greatly influenced by how long and how thick the strings are, and by their arrangement in the high, middle and lower registers.
• The subtle nuances of the piano are determined, to a large degree, by the number and strength of the harmonics generated in addition to the fundamental tone. In the piano's case these harmonics are not whole number multiples of the fundamental tone; rather they are gradually diverged. This divergence is another key factor to consider when designing the stringing scale.



• High class models use an aliquot type pressure bar. On the underside of the pressure bars in the upper registers, a diagonally raised protrusion is used. This increases the holding force and defines the length of the resonance strings in an accurate relationship with the speaking string length. Therefore, this system produces a harmonic structure that is more optimal that that produced by most traditional pressure bars, and helps create a piano tone of strength and beauty.
• The tonal quality of the lower registers is greatly influenced by the resonance over the entire piano frequency range. Flexible copper-wrapped strings with sufficient mass are necessary to produce deep and clear low tones.
• The core wire and copper wrapping of the lower register's strings have been fabricated to act as a single unit. In addition, highly flexible and precise core wire and pure copper wire wrapping have been sued. This enables the energy of the strings to be completely and efficiently converted into sound.
• When progressing from the wire wrapped strings of the lower registers to the unwrapped strings of the middle registers, keeping the tone uniform becomes a very difficult design problem.
• A longer string does not necessarily resonate well. The relationship with the bridge is very important.
• By utilizing an "over-hanging" long bridge, high class models insure the tone a smooth transition from the lower range into the mid-range.
• In addition, by using a curved short bridge, high class models more accurately reflect the best design principles and improve the tonal quality of the lower registers, bringing forth a rich and full sound. The tone also makes a smooth transition where the piano changes form single to double strings.



Fabrication Technology

• Highly advanced techniques are required to accurately wrap the copper wrappings around the music wire core. The tension of the copper wrapping, wrapping angle, and wrapping speed will all affect the tone.
• Using its own in-house developed, specialized machinery, Yamaha is producing high quality and wrapped wire of extremely high consistency and stability.
• The setting and tensioning of the strings is also done by skilled technicians using Yamaha's specialized machinery. This also insures accuracy and uniformity.