A metronome (from Ancient Greek μέτρον (métron) 'measure' and νόμος (nómos) 'law') is a device that produces an audible click or other sound at a uniform interval that can be set by the user, typically in beats per minute (BPM). Metronomes may also include synchronized visual motion, such as a swinging pendulum or a blinking light. Musicians—and others including dancers, athletes, and health professionals—often practise with a metronome to improve their timing, especially the ability to maintain a steady tempo with a regular beat or pulse. Composers and conductors often use numerical metronome markings to communicate their preferred tempos to musicians preparing for a performance.
A type of metronome was among the inventions of Andalusian polymath Abbas ibn Firnas (810–887). In 1815, German inventor Johann Maelzel patented a mechanical, wind-up metronome as a tool for musicians, under the title "Instrument/Machine for the Improvement of all Musical Performance, called Metronome".[1] In the 20th century, electronic metronomes and software metronomes were invented.
When interpreting emotion and other qualities in music, performers seldom play exactly on every beat. In a musically expressive performance, the pulse generally does not align with the clicks of a metronome.[2][3] This has led some musicians to criticize use of a metronome, because "musical time is replaced by clock time".[4]
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