Editing Metronome (section)

===Mechanical metronomes===
[[File:Metronome Mälzel 1.jpg|Maelzel's Metronome|thumb|right]]
Historical credit for the mechanical metronome is spread across Spanish, Italian, French, Dutch and German contributors.

According to historian [[Lynn Townsend White Jr.]], the Andalusian [[Inventions in the Islamic world|inventor]] Abbas Ibn Firnas created "some sort of metronome" in the 9th century.<ref>[[Lynn Townsend White Jr.|White, Lynn Townsend]] (Spring 1961). "Eilmer of Malmesbury, an Eleventh Century Aviator: A Case Study of Technological Innovation, Its Context and Tradition", ''[[Technology and Culture]]'' '''2''' (2), p. 97–111 [100]: "Ibn Firnas was a polymath: a physician, a rather bad poet, the first to make glass from stones (quartz), a student of music, and inventor of some sort of metronome."</ref><ref>{{Cite book |last=Maqqarī |first=Abu-'l-ʻAbbās Aḥmad Ibn-Muḥammad al- |url=https://books.google.com/books?id=iaxCAAAAcAAJ&dq=metronome+Firnas&pg=RA2-PA426 |title=The History of the Mohammedan Dynasties in Spain: Extracted from the Nafhu-t-Tib Min Ghosni-l-Andalusi-r-Rattib ... by Aḥmad B. Muḥammad Al Makkari |volume=1 |date=1840 |publisher=Oriental Translation Fund |language=en |pages=148, 426}}</ref> [[Galileo Galilei]] studied and discovered key concepts involving the [[pendulum]] in the late 16th and early 17th centuries, famously inspired by a steadily swaying chandelier in [[Pisa Cathedral]].<ref name=pendulum>{{cite book |url=https://books.google.com/books?id=YUHyhL8MyIQC&pg=PA41 |last=Murdin |first=Paul |title=Full Meridian of Glory: Perilous Adventures in the Competition to Measure the Earth |publisher=Springer |year=2008 |pages=41–43 |isbn=978-0-387-75533-5}}</ref> In 1696, musician [[Étienne Loulié]] built a pendulum-based "[[chronomètre]]", consisting of a lead weight hanging from an adjustable string alongside a {{convert|6|ft|m|0|adj=on}} vertical ruler. However, his design produced no sound, and did not have an [[escapement]] mechanism to keep the pendulum in motion.<ref>{{cite web | url = https://www.franzmfg.com/history.htm | title = A Brief History of the Metronome | publisher = Franz Manufacturing Company | access-date = 2010-04-02 | url-status = live | archive-url = https://web.archive.org/web/20100324143043/http://www.franzmfg.com/history.htm | archive-date = 2010-03-24 }}</ref> To get the correct tempo with this type of visual device, a musician would need to watch the pendulum as if watching a conductor's baton.

The more-familiar mechanical musical chronometre was invented by [[Dietrich Nikolaus Winkel]] in [[Amsterdam]] in 1814, based on a [[Mainspring|spring]]-powered, inverted pendulum rod with fixed and adjustable weights to achieve compactness. Through questionable practice,<ref>[https://books.google.com/books?id=HugqAAAAYAAJ&pg=PA17 "The Metronome"]; ''The Harmonicon'', Vol. 8 (1830), p. 17.</ref> [[Johann Nepomuk Maelzel|Johann Maelzel]], incorporating Winkel's ideas, added a numerical scale, called it a metronome, and started mass-manufacturing the pyramid-shaped device in 1816 under his own name: "Maelzel's Metronome." The original text of Maelzel's patent in England (1815) can be downloaded.<ref name=maelzel>[https://books.google.com/books?id=dO80AAAAMAAJ&pg=PA7 "Specification of the Patent granted to John Maelzel, ... which he denominates a Metronome or Musical Time-keeper. Dated December 5, 1815."]. ''The Repertory of Arts, Manufactures, and Agriculture'', Vol. 33 (1818), pp. 7–13. ([https://books.google.com/books?id=-b8-AAAAcAAJ&pg=PA7 alternative link])</ref>

Maelzel's mechanical metronome uses an adjustable weight on an inverted pendulum rod to control tempo. The weight slides up the pendulum rod to decrease tempo, or down to increase tempo. (This mechanism is also called a double-weighted pendulum, because there is a second, fixed weight on the other side of the pendulum pivot, inside the metronome case.) The pendulum swings back and forth in tempo, while a mechanism inside the metronome produces a clicking sound with each [[oscillation]]. A mechanical metronome does not need an [[electric battery]], but runs from a spring-wound [[clockwork]] escapement.<ref name=maelzel/> For uniform beats, the metronome should be placed on a hard, level, unmoving surface, and away from any strong magnets. Small variations in pendulum speed can also result from differences in temperature, air pressure, or gravity.<ref name=pendulum/>

Since Maelzel's era, musical tempo is almost always measured in beats per minute (BPM). Metronomes often display both BPM numbers and traditional [[tempo markings]], which are written words conveying a range of tempos and an associated character. For example, the Italian term ''Vivace'' indicates a tempo typically between 156 and 176 BPM, but it also communicates that the music should be played with a lively character.<ref>{{cite web|url=https://theonlinemetronome.com/metronome-tempo-markings-defined.html|title=Common Tempo Markings in Music|first=Andrew|last=Swinney|work=The Online Metronome|access-date=2024-03-06}}</ref>

A mechanical metronome's tempo is usually adjustable from 40 to 208 BPM. The most-common arrangement of tempos on a Maelzel metronome begins with 40 beats per minute
and increases by 2 BPM: 42 44 46 48 50 52 54 56 58 60,
then by 3 BPM: 63 66 69 72,
then by 4 BPM: 76 80 84 88 92 96 100 104 108 112 116 120,
then by 6 BPM: 126 132 138 144,
then by 8 BPM: 152 160 168 176 184 192 200 208.
Some modern metronomes allow adjustment to more-precise tempos (e.g., increasing 120 to 121), but such a difference is hardly perceptible.<ref>{{cite web |last=Paterson |first=Robert |title=Standard Metronome Timings and Ratios |date=2006 |url=https://issuu.com/robertpaterson/docs/standard-metronome-timings-and-rati |access-date=2020-07-04}}</ref>