Augmented unison
In modern Western tonal music theory an augmented unison or augmented prime[3] is the interval between two notes on the same staff position, or denoted by the same note letter, whose alterations cause them, in ordinary equal temperament, to be one semitone apart.[4] The term, in its French form unisson superflu, appears to have been coined by Jean-Philippe Rameau in 1722, who also called this interval a minor semitone (semiton mineur).[5] Historically, this interval, like the tritone, is described as being "mi contra fa", and therefore is the "diabolus in musica" (the Devil in music).It is found once in Rameau's writings, for example,[5] as well as subsequent French, German, and English sources.[9] Some theoreticians make a distinction for this diminished form of the unison, stating it is only valid as a melodic interval, not a harmonic one.
InverseDiminished octaveSemitonesInterval classJust intervalJust intonationmusic theoryintervalequal temperamentsemitoneunisonJean-Philippe Rameautritone12-toneenharmonicminor secondRameau'sFalse relationList of musical intervalsList of pitch intervalsJohann Georg AlbrechtsbergerIgnaz Seyfried (Ritter von)Alexandre ChoronHenry Charles BanisterCastil-BlazeThe Guild of Carillonneurs in North AmericaHorst LeuchtmannGustav SchillingDaniel Gottlob TürkFriedrich Wilhelm MarpurgStefan KostkaAndrew SurmaniJohann Adam HillerBurrows, TerryRushton, JulianGrove Music OnlineAndreas WerckmeisterIntervalsTwelve-semitonefourthoctavesecondseventheleventhtwelfththirteenthfourteenthfifteenth24-tone equal temperamentNeutralquarter tonemajor fourthminor fifthJust intonations7-limitseptimal quarter toneseptimal third toneseptimal chromatic semitoneseptimal diatonic semitonesupermajor secondsubminor thirdsupermajor thirdsubminor fifthsupermajor fourthsubminor seventhHigher-limitminor diatonic semitoneMicrotone5-limitPseudo-octavePythagorean intervalSubminor and supermajorPythagorean limmaPythagorean apotomeMajor limmaUndecimal quarter toneCommasPythagorean commaSyntonic commaHoldrian commaSeptimal commaLesser diesisGreater diesisSeptimal diesisDiaschismaSemicommaSeptimal semicommaKleismaSeptimal kleismaSchismaBreedsmaRagismaMillioctaveSavartDitoneSemiditoneIncomposite interval