Everything about Cent Music totally explained
The
cent is a
logarithmic unit of measure used for musical
intervals. Typically cents are used to measure extremely small intervals, or to compare the sizes of comparable intervals in different
tuning systems, and in fact the interval of one cent is much too small to be heard between successive notes.
Alexander J. Ellis based the measure on the
acoustic logarithms decimal semitone system developed by
Gaspard de Prony in the 1830s, at
Robert Holford Macdowell Bosanquet's suggestion, and introduced it in his edition of
Hermann von Helmholtz's
On the Sensations of Tone. It has become the standard method of representing and comparing musical pitches and intervals with relative accuracy.
Use
1200 cents are equal to one
octave — a frequency ratio of 2:1 — and an
equally tempered semitone (the interval between two adjacent piano keys) is equal to 100 cents. This means that a cent is precisely equal to 2
1/1200, the 1200th root of 2, which is approximately 1.0005777895065548592967925757932, or
To compare different tuning systems, convert the various interval sizes into cents. For example, in
just intonation the major third is represented by the frequency ratio 5:4. Applying the formula at the top shows this to be about 386 cents. The equivalent interval on the equal-tempered piano would be 400 cents. The difference, 14 cents, is about a seventh of a half step, easily audible. The
just noticeable difference for this unit is about 6 cents.
Human perception
It is difficult to establish how many cents are perceptible to humans; this accuracy varies greatly from person to person. One author stated that humans can distinguish a difference in pitch of about 5-6 cents. The threshold of what is perceptible also varies as a function of the
timbre of the pitch: in one study, changes in tone quality negatively impacted student musicians' ability to recognize as out-of-tune pitches that deviated from their appropriate values by +/- 12 cents. It has also been established that increased tonal context enables listeners to judge pitch more accurately.
When listening to pitches with
vibrato, there's evidence that humans perceive the mean frequency as the center of the pitch. One study of vibrato in western vocal music found a variation in cents of vibrato typically ranged between ±34 cents and ±123 cents, with a mean variation of ±71 cents; the variation was much higher on
Verdi opera arias.
Normal adults are able to recognize pitch differences of as small as 25 cents very reliably. Adults with
amusia, however, have trouble recognizing differences of less than 100 cents and sometimes have trouble with these or larger intervals.
Sound files
The following .ogg files play various cents intervals. In each case the first note played is middle C. The next note a C which is sharper by the assigned cents value. Finally the interval is played.
Further Information
Get more info on 'Cent Music'.
|
External Link Exchanges
Do you know how hard it is to get a link from a large encyclopaedia? Well we're different and will prove it. To get a link from us just add the following HTML to your site on a relevant page:
<a href="http://cent__music.totallyexplained.com">Cent (music) Totally Explained</a>
Then simply click through this link from your web page. Our crawlers will verify your link, extract the title of your web page and instantly add a link back to it. If you like you can remove the words Totally Explained and embed the link in article text.
As long as your link remains in place, we'll keep our link to you right here. Please play fair - our crawlers are watching. Your site must be closely related to this one's topic. Any kind of spamming, dubious practises or removing the link will result in your link from us being dropped and, potentially, your whole site being banned. |
