Metronome Mark
A marking such as quarter note = 120 that fixes the number of beats per minute
Related
A metronome mark is a figure such as ♩ = 120 at the head of a score or section, fixing how many of a given note value occur per minute. It turns a character word like Allegro into a measurable number, usually written "note value = number", with ca. added when the value is approximate.
The note value is the key to reading it: ♩ = 120 and ♪ = 120 are entirely different, and in 6/8 the mark is often a dotted quarter because that is the real beat. Nor is the figure absolutely precise — different halls and ensembles make the same number feel faster or slower. It is a coordinate, not a command.
A common mistake is to confuse BPM with the time signature. The signature governs how each bar is grouped; the metronome mark governs how fast the minutes pass.
Sources
- 节拍器标记的写法与历史，参 The New Grove Dictionary of Music and Musicians, "Metronome"；本文为原创表述
Used for fact-checking only; all prose is original.