Intervals
The diatonic intervals are usually understood as those between some pair of notes both drawn from the same diatonic scale. Intervals that cannot be so derived are then called chromatic intervals. Because diatonic scale is itself ambiguous, this way of distinguishing intervals is also ambiguous. For example, the interval B♮–E♭ (a diminished fourth, occurring in C harmonic minor) is considered diatonic if the harmonic minor scale is considered diatonic; but it is considered chromatic if the harmonic minor scale is not considered diatonic.
Additionally, the label chromatic or diatonic for an interval may be sensitive to context. For instance, in a passage in C major, the interval C–E♭ could be considered a chromatic interval because it does not appear in the prevailing diatonic key; conversely in C minor it would be diatonic. This usage is still subject to the categorization of scales as above, e.g. in the B♮–E♭ example above, classification would still depend on whether the harmonic minor scale is considered diatonic.
Read more about this topic: Diatonic And Chromatic
Famous quotes containing the word intervals:
“Fishermen, hunters, woodchoppers, and others, spending their lives in the fields and woods, in a peculiar sense a part of Nature themselves, are often in a more favorable mood for observing her, in the intervals of their pursuits, than philosophers or poets even, who approach her with expectation. She is not afraid to exhibit herself to them.”
—Henry David Thoreau (1817–1862)
“It can be demonstrated that the child’s contact with the real world is strengthened by his periodic excursions into fantasy. It becomes easier to tolerate the frustrations of the real world and to accede to the demands of reality if one can restore himself at intervals in a world where the deepest wishes can achieve imaginary gratification.”
—Selma H. Fraiberg (20th century)
“Unless the people can choose their leaders and rulers, and can revoke their choice at intervals long enough to test their measures by results, the government will be a tyranny exercised in the interests of whatever classes or castes or mobs or cliques have this choice.”
—George Bernard Shaw (1856–1950)