Augmented seventh Adding a diesis to this makes up an octave. Hence, this interval's complement, the diminished second, is often referred to as a diesis. Augmented seventh In classical music from Western culture, an augmented seventh is an interval produced by widening a major seventh by a chromatic semitone. For instance, the interval from C to B is a major seventh, eleven semitones wide, and both the intervals from C to B, and from C to B are augmented sevenths, spanning twelve semitones. Being augmented, it is classified as a dissonant interval. However, it is enharmonically equivalent to the perfect octave. Since
Pentatonic scale Pentatonic scale A pentatonic scale is a musical scale with five notes per octave, in contrast to the more familiar heptatonic scale that has seven notes per octave (such as the major scale and minor scale). Pentatonic scales were developed independently by many ancient civilizations—an indication that pentatonic scales are based upon a naturally occurring phenomenon. They are still used all over the world, for example (just to name a few) Chinese music and US country music and blues. There are two types of pentatonic scales: those with semitones (hemitonic) and those without (anhemitonic). Pentatonic scales occur in the following