Metronome

A metronome is a device that produces an audible beat—a click or other sound—at regular intervals that the user can set in beats per minute (BPM). Musicians use the device to practice playing to a regular pulse. Metronomes typically include synchronized visual motion (e.g., swinging pendulum or blinking lights).

The metronome dates from the early 9th century, Abbas ibn Firnas (810-887 AD), was patented by Johann Maelzel in 1815 as a tool for musicians, under the title "Instrument/Machine for the Improvement of all Musical Performance, called Metronome".

Musicians practice with metronomes to improve their timing, especially the ability to stick to a tempo. Metronome practice helps internalize a clear sense of timing and tempo. Composers often use a metronome as a standard tempo reference—and may play or sing their work to the metronome to derive beats per minute if they want to indicate that in a composition.

When interpreting emotion and other qualities in music, performers seldom play exactly on every beat. Typically, every beat of a musically expressive performance metronome doesn't align exactly with each click of a metronome. This has led some musicians to criticize use of a metronome, because metronome time is different from Musical Time. Some go as far as to suggest that musicians shouldn't use metronomes at all, and have leveled criticism at metronome markings as well. See Criticism of metronome use.

Those in favour of metronome use understand this as a criticism of metronome technique as commonly practiced by musicians, rather than criticism of the tool as such. Their response has been to develop better methods of metronome technique to address the various issues raised by the critics. See Metronome Technique. These techniques however aren't widely known by musicians generally, including many critics of metronome use. Metronome technique has developed, but the body of published information is small—so some critics may think that metronome technique consists only of playing music along with the metronome. In his book, Metronome Techniques, Frederick Franz maintains that those who disparage metronomes as "making you mechanical" misunderstand their proper use.

The word metronome first appeared in English c. 1815 and is Greek in origin: metron "measure" and nomos "regulating, law."

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