# Dictionary Definition

octave

### Noun

1 a feast day and the seven days following
it

2 a musical interval of eight tones [syn:
musical
octave]

3 a rhythmic group of eight lines of verse

# User Contributed Dictionary

## English

### Noun

- (music theory) An interval of eight tones on a diatonic scale,
representing a doubling or halving in pitch.
- The melody jumps up an octave at the beginning, then later drops back down an octave.
- The singer was known for astounding clarity over her entire five-octave range.

- (music theory) The pitch an octave higher than a given pitch.
- The bass starts on a low E, and the tenor comes in on the octave.

- The eighth defensive position, with the sword hand held at waist height, and the tip of the sword out straight at knee level.

#### Translations

interval

- Croatian: oktava
- Icelandic: áttund
- Japanese: オクターブ

pitch octave higher than a given pitch

- Croatian: oktava

(fencing) the eigth defensive position

# Extensive Definition

In music, an octave (sometimes
abbreviated 8va or P8) is the interval
between one musical pitch and
another with half or double its frequency.

## Examples

For example, if one note has a frequency of 400
Hz, the note
an octave above it is at 800 Hz, and the note an octave below is at
200 Hz. The ratio of frequencies of two notes an octave apart is
therefore 2:1. Further octaves of a note occur at 2n times the
frequency of that note (where n is an integer), such as 2, 4, 8,
16, etc. and the reciprocal of that series. For example, 50 Hz and
400 Hz are one and two octaves away from 100 Hz because they are ½
(or 2 −1) and 4 (or 22) times the frequency,
respectively. However, 300 Hz is not a whole number octave above
100 Hz, despite being a harmonic of 100 Hz.

## Musical relevance

After the unison, the octave is the
simplest interval in music. The human ear tends to hear both
notes as being essentially "the same". For this reason, notes an
octave apart are given the same note name in the Western system of
music
notation—the name of a note an octave above A is also
A. This is called octave equivalency, and is closely
related to harmonics.
This is similar to enharmonic
equivalency, and less so transpositional
equivalency and, less still, inversional
equivalency, the latter of which is generally used only in
counterpoint,
musical
set theory, or atonal
theory. Thus all C♯s, or all 1s (if C = 0), in
any octave are part of the same pitch class.
Octave equivalency is a part of most musics, but is far from
universal in "primitive" and early music
(e.g., Nettl, 1956; Sachs & Kunst, 1962). However, monkeys
experience octave equivalency, and its biological basis apparently
is an octave mapping of neurons in the auditory thalamus of the
mammalian brain http://web.telia.com/~u57011259/eng7.htm
and the perception of octave equivalency in self-organizing neural
networks can form through exposure to pitched notes, without any
tutoring, this being derived from the acoustical structure of those
notes (Bharucha 2003, cited in Fineberg 2006).

While octaves commonly refer to the perfect
octave (P8), the interval of an octave in music theory encompasses
chromatic alterations within the pitch class, meaning that G to G♯
(13 semitones higher) is an augmented octave (A8), and G to G♭ (11
semitones higher) is a diminished octave (d8). The use of such
intervals is rare, as there is frequently a more preferable
enharmonic notation
available, but these categories of octaves must be acknowledged in
any full understanding of the role and meaning of octaves more
generally in music.

## Electrical relevance

In electronics design, an amplifier or filter may
be stated to have a frequency response of ±6dB per octave over a
particular frequency range, which signifies that the power gain
changes by ±6 decibels
(a factor of four in power), or more precisely 6.0206 decibels when
the frequency changes by a factor of 2. This response is equivalent
to ±20dB per decade
(a change in frequency by a factor of 10).

Example

A magnitude of 400 (52 dB) at 4 kHz decreases as
frequency increases at −2 dB/octave. What is the
magnitude at 13 kHz?

- \text = \log_2\left(\frac\right) = 1.7

- \text_ = 52\text + (1.7\text \times -2\text) = 48.6\text = 269.\,

## Other uses of term

As well as being used to describe the
relationship between two notes, the word is also used when speaking
of a range of notes that fall between a pair an octave apart. In
the diatonic
scale, and the other standard heptatonic scales of Western
music, this is 8 notes if one counts both ends, hence the name
"octave", from the Latin octavus, from octo (meaning "eight"). In
the chromatic
scale, this is 13 notes counting both ends, although
traditionally, one speaks of 12 notes of the chromatic scale, since
there are 12 intervals. Other scales may have a different number of
notes covering the range of an octave, such as the Arabic classical
scale with 17, 19, or even 24 notes, but the word "octave" is still
used.

In terms of playing an instrument, "octave" may
also mean a special effect involving playing two notes that are an
octave apart at the same time. This effect may have to be created
by the musician. However, some instruments are purposely tuned or
designed to produce this effect, for example, the twelve-string
guitar and the octave harmonica.

In most Western
music, the octave is divided into 12 semitones (see musical
tuning). These semitones are usually equally spaced out in a
method known as equal
temperament.

Many times singers will be described as having a
four-octave range or a five-octave range. This is technically a
misnomer, and is described here: five-octave
vocal range. It is important to remember when hearing this
description that a piano has octaves total.

Many of the dual toned sirens manufactured by the
Sentry Siren Company use an octave ratio on their sirens, usually ,
which produces a octave.

## Notation

The notation 8va is sometimes seen in sheet music,
meaning "play this an octave higher than written." 8va stands for
ottava, the Italian
word for octave. Sometimes 8va will also be used to indicate a
passage is to be played an octave lower, although the similar
notation 8vb (ottava bassa) is more common. Similarly, 15ma (quindicesima) means
"play two octaves higher than written" and 15mb (quindicesima
bassa) means "play two octaves lower than written." Col 8 or c. 8va
stands for coll'ottava and means "play the notes in the passage
together with the notes in the notated octaves". Any of these
directions can be cancelled with the word loco, but often a dashed
line or bracket indicates the extent of the music affected.

For music-theoretical purposes (not on sheet
music), octave can be abbreviated as P8 (which is an abbreviation
for Perfect Eighth, the interval between 12 semitones or an
octave).

## See also

## Sources

- Burns, Edward M. (1999). "Intervals, Scales, and Tuning", The Psychology of Music second edition. Deutsch, Diana, ed. San Diego: Academic Press. ISBN 0-12-213564-4.
- Fineberg, Joshua (2006). Classical Music, Why Bother?". Routledge. ISBN 041597173X. Cites Bharucha (2003).
- Sachs, C. and Kunst, J. (1962). In The wellsprings of music'', ed. Kunst, J. The Hague: Marinus Nijhoff.

## External links

octave in Arabic: مسافات موسيقية

octave in Bulgarian: Октава

octave in Catalan: Octava

octave in Czech: Oktáva (hudba)

octave in Danish: Oktav

octave in German: Oktave

octave in Estonian: Oktaav

octave in Spanish: Octava

octave in Esperanto: Okto

octave in Persian: اوکتاو

octave in French: Octave (musique)

octave in Western Frisian: Oktaaf

octave in Galician: Oitava

octave in Korean: 옥타브

octave in Croatian: Oktava

octave in Indonesian: Oktaf

octave in Icelandic: Áttund

octave in Italian: Ottava (musica)

octave in Hebrew: אוקטבה

octave in Latvian: Oktāva

octave in Lithuanian: Oktava

octave in Hungarian: Oktáv

octave in Dutch: Octaaf (muziek)

octave in Japanese: オクターヴ

octave in Norwegian: Oktav

octave in Norwegian Nynorsk: Oktav

octave in Polish: Oktawa (interwał)

octave in Portuguese: Oitava

octave in Russian: Октава

octave in Simple English: Octave

octave in Serbian: Октава (музика)

octave in Finnish: Oktaavi

octave in Swedish: Oktav

octave in Thai: อ็อกเทฟ

octave in Turkish: Oktav

octave in Ukrainian: Октава

octave in Chinese: 八度

# Synonyms, Antonyms and Related Words

English horn, Octateuch, Spenserian stanza,
antistrophe,
bassoon, block flute,
bombard, book, bourdon, burden, canto, cello, chorus, claribel, clarinet, clarion, concert flute,
consecutive intervals, contraoctave, cornet, cornopean, couplet, cromorna, cymbel, degree, diapason, diatessaron, diatonic
interval, diatonic semitone, distich, double contraoctave,
dulciana, eight, eighter from Decatur,
eighth, enharmonic
diesis, enharmonic interval, envoi, epode, fifth, flute stop, foundation
stop, four-foot octave, four-line octave, fourniture, fourth, gamba, gedeckt, gemshorn, great octave, half
step, halftone,
harmonic flute, heptastich, hexastich, hybrid stop,
interval, koppel flute,
larigot, less semitone,
line, measure, melodia, melodic interval,
mixture, monostich, mutation stop,
nazard, note, oboe, octad, octagon, octahedron, octameter, octastich, octastyle, octavo, octet, octonary, octosyllable, ogdoad, one-line octave, organ
stop, ottava, ottava
alta, ottava bassa, ottava rima, parallel octaves, pentastich, piccolo, plein jeu, posaune, principal, quatrain, quint, quintaten, rank, ranket, reed stop, refrain, register, rhyme royal, rohr
flute, second, semitone, septet, sesquialtera, sestet, seventh, sextet, shawm, sixth, small octave, spitz flute,
stanza, stave, step, stop, stopped diapason, stopped
flute, strain, string
diapason, string stop, strophe, subcontraoctave,
syllable, tercet, terza rima, tetrastich, third, tierce, tone, tone row, tremolo, triplet, tristich, trombone, trumpet, twelfth, two-foot octave,
two-line octave, unda maris, unison interval, utas, verse, vibrato, viola, voix celeste, vox angelica,
vox humana, whole step