Engelenpoort Tuning fork 4096 Hz. Delivered with beater and storage case.

A tuning fork, or diapason, is a two-pronged metal fork that produces a tone with a precisely known pitch when vibrated. A tuning fork is constructed in such a way that the tone produced is hardly affected by temperature and humidity. A good tuning fork produces very few overtones, so the sound approximates a pure sine wave. Some tuning forks have a sliding metal clip so that other tones than the standard frequency, which is usually 440 or 880 Hz, can be played. The invention of the tuning fork is attributed to John Shore in 1711. John Shore was Sergeant Trumpeter at the English Court. Both Purcell and Handel wrote trumpet parts especially for him. A tuning fork is used to tune a musical instrument. The note of the musical instrument that corresponds to the pitch of the tuning fork is set-tuned - so that it matches the pitch of the tuning fork. Singers sometimes use a tuning fork to hit the right note. Most tuning forks are tuned to the chamber tone, the a', with a frequency (nowadays) of 440 Hz. There are also tuning forks for other pitches, also for pitches other than a'. To hear the soft tone of a tuning fork properly, the tuning fork is held with the round end against the head (bone conduction), mounted on a resonator, or pressed onto a tabletop.