Cent: Difference between revisions

m Conversion: cleanup
m Interwiki
 
(2 intermediate revisions by one other user not shown)
Line 2: Line 2:
| en = Cent
| en = Cent
| de = Cent
| de = Cent
| es = Centésimas
| es = Cent
| ja = セント
| ja = セント
| ko = 센트
| ko = 센트
Line 8: Line 8:
}}
}}
{{Wikipedia|Cent (music)}}
{{Wikipedia|Cent (music)}}
The '''cent''' (symbol: '''¢''') is a [[unit of interval size]] equal to exactly 1/100th (or 1%) of a [[12edo]] [[semitone (interval size measure)|semitone]]. In other words, cents divide the half step (semitone) of 12edo into 100 equal parts. First proposed in the late 19th century by {{w|Alexander John Ellis|Alexander J. Ellis}}, the cent may also be defined as the {{w|logarithm}} base 1200th root of 2 of a ratio.
The '''cent''' (symbol: '''¢''') is a [[unit of interval size]] equal to exactly 1/100 (or 1%) of a [[12edo]] [[semitone (interval size measure)|semitone]]. In other words, cents divide the half step (semitone) of 12edo into 100 equal parts. First proposed in the late 19th century by {{w|Alexander John Ellis|Alexander J. Ellis}}, the cent may also be defined as the {{w|logarithm}} base 1200th root of 2 of a ratio.


Cents are often used to express the size of intervals in different tuning systems, sometimes to express the accuracy of the representation of a [[just intonation]] [[interval]] in a given system.
Cents are often used to express the size of intervals in different tuning systems, sometimes to express the accuracy of the representation of a [[just intonation]] [[interval]] in a given system.
Line 16: Line 16:


== Conversion ==
== Conversion ==
{{See also| Ratio #Conversion }}
=== Ratio to cents ===
=== Ratio to cents ===
To find the size ''s'' of an interval in cents from its ratio ''r'', calculate the [[log2|binary logarithm]] (log<sub>2</sub>) of its [[frequency ratio]], and multiply it by 1200.
To find the size ''s'' of an interval in cents from its ratio ''r'', calculate the [[log2|binary logarithm]] (log<sub>2</sub>) of its [[frequency ratio]], and multiply it by 1200.