What is A-440?

For hundreds of years, there was no universal standard of pitch. The A in other parts of the world, and even parts same country were different. In the seventeenth century a uniform pitch called the Mean “pitch” was established “A” was set at 424.2 cycles per second this pitch was used for a period of two hundred years.

In 1936, The United States adopted the American standard pitch. Musicians agreed to standardize the pitch of the note to which they tuned their instruments. They agreed to tune to an A (A above middle "C") that vibrated at a frequency of 440 cycles per second. Once this standard was established, pianos began being designed so their instruments plates could be tuned to this pitch as well. When a piano is properly tuned, the A above middle C is "set" to 440 cycles per second. Now days we refer to cycles per second as Hertz or Hz. Three years later in 1939 the rest of the countries accepted A440 as a new world standard.

<