Cross-stringing (sometimes called overstringing) is a method of arranging piano strings inside the case of a

piano The piano is a stringed keyboard instrument in which the strings are struck by wooden hammers that are coated with a softer material (modern hammers are covered with dense wool felt; some early pianos used leather). It is played using a keyboa ...

so that the strings are placed in a vertically overlapping slanted arrangement, with two heights of

bridge A bridge is a structure built to span a physical obstacle (such as a body of water, valley, road, or rail) without blocking the way underneath. It is constructed for the purpose of providing passage over the obstacle, which is usually somethi ...

s on the soundboard instead of just one. This permits larger, but not necessarily longer, strings to fit within the case of the piano. The invention of cross-stringing in the 1820s is variously credited to Alpheus Babcock and Jean-Henri Pape. The first patented use in grand pianos in the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...

was by Henry Steinway Jr. in 1859. In the late 19th century, cross-stringing gradually took the place of straight-stringing, in which all the strings are perpendicular to the keyboard and do not overlap. The advantages of cross-stringing is that the case of the piano can be smaller, the bass strings can be longer and the placement of the bass strings is in the center of the piano case, where they receive more resonance than when placed at the side. Cross-stringing is criticized by some as producing a "murky" sound. According to the pianist Gwendolyn Mok, "If you look inside your own piano, you will notice that the strings are all crossing each other. With the straight strung piano you get distinct registral differences--almost like listening to a choir where you have the bass, tenor, alto, and soprano voices. It is very clear and there is no blending or homogenizing of the sound."Gwendolyn Mok in Conversation with Thad Carhart
, www.gwendolynmok.com Some Challen pianos made in the 1920s are "double overstrung", where the strings are at 3 different heights and cross over in 2 different locations.

References

Piano {{Music-theory-stub