The New World – Steinway & Sons | Instrument and Innovation

The biggest playing field of experimentation at Steinway & Sons is and has always been the grand piano. Especially Henry jr. (1831–1865) contributed largely to its technical development. His achievements include the cast iron plate with flange, the free-swinging soundboard, the relocation of the bridge to the center of the soundboard and the cross-string arrangement of the bass strings in a grand piano. These components were adopted by numerous American and European piano  manufacturers. 

Theodor (1825–1889) also contributed crucially to the development of the grand piano. In Braunschweig he had already worked together with the physician and polymath Hermann von Helmholtz (1821–1894). They co-developed the duplex-scale, for which Steinway registered the patent in 1872 (US-Patent No. 126.848). In addition, Theodor’s most important inventions include the construction of a cast frame that can withstand up to 35 tons of string tension, and the rim-bending block (US-Patent No. 229.198). The latter is used frequently in many workshops until today.

The grand piano as it is built and played today is essentially the same one as developed by Steinway & Sons until the end of the 19th century. 

Duplex-Scale
The string section between the bridge and the cast iron frame of the grand piano is called the duplex scale. This is the section that lies outside the string area struck by the hammers. In terms of sound, it plays an important role: It enriches the string vibration with high frequencies, and adds brilliance to the sound.

Rim-Bending Block
The rim is the piano case. Theodor Steinweg (1825–1889) developed a procedure, with which the frame could be pressed into the curved shape in one piece: Several layers of hard wood (maple, mahogany) were glued together and dried on a specific bending block for several hours. For the procedure and the bending press, Theodor registered a patent (US-Patent No. 229.198) in 1888. It is used in piano-making until today.
Up until Theodor’s invention, it was the custom to assemble the frame using several parts. The wood for the typical S-curve was bent using steam, and glued to the adjacent housing parts: a time-consuming and error-prone procedure.