Augmented third
musical interval of five semitones spanning three staff positions (e.g. from C to E♯); enharmonically equivalent to the perfect fourth
In classical music from Western culture, an augmented third () is an interval of five semitones. It may be produced by widening a major third by a chromatic semitone. For instance, the interval from C to E is a major third, four semitones wide, and both the intervals from C♭ to E, and from C to E♯ are augmented thirds, spanning five semitones.
Being augmented, it is considered a dissonant interval.
Its inversion is the diminished sixth, and its enharmonic equivalent is the perfect fourth.
The just augmented third, E♯, is 456.99 cents or 125:96. The Pythagorean augmented third, E♯+++, is 521.51 cents or 177147:131072, eleven just perfect fifths.
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This entry incorporates text from “Augmented third” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.