Chapter+SIx

Define the following terms:

Augmented interval- An interval one half step larger than a major or perfect interval

Compound interval- An interval larger than an octave

Consonance- A relative term based on acoustic properties of sound and on the norms of compositional practice. A consonant harmonic interval- unison, third fifth, sixth, or octave- is considered pleasing to hear

Diminished interval- An interval one half step smaller than a minor or perfect interval

Generic pitch interval- The distance between two pitches as measured by the number of steps between their letter names

Imperfect consonance- The intervals of a third and sixth

Interval Class- All pitch intervals that can be made from one pair of pitch classes (or transpositions of these pitch classes by the same distance) belong to a single interval class.

Inversion of interval- Two intervals that, when combined, span an octave. When inverted, major intervals become minor, diminished become augmented, and perfect stay perfect. The generic interval numbers of inversionally related intervals sum to 9.

Perfect consonance- The intervals of a unison, fourth, fifth, and octave. The harmonic interval of a fourth is treated as a dissonance in common-practice style.

Pitch interval- the musical space between two pitches, described either with tonal labels or by the number of half steps from one pitch to the other. Unordered pitch intervals measure distance; ordered pitch intervals measure distance and direction

Tritone- An interval made up of three whole tones or six semitones: an augmented fourth or diminished fifth. By some definitions only an augmented fourth is a tritone, since in this spelling the interval spans three whole steps.

Unison- The interval size 1, or the distance from a pitch to itself; interval 0 if measured in semitones

Questions:

1. What information is missing from generic pitch-interval names? What is the difference between melodic intervals and harmonic intervals?

The information that is missing is the number of half steps in between two pitches. The difference between melodic intervals and harmonic intervals is that melodic intervals are pitch intervals measured between successive pitches, and harmonic intervals are measured between simultaneous pitches.

2. Which generic intervals are considered consonances? Dissonances?

The unison, third, fifth, sixth, and octave intervals are considered consonances. The second, seventh, and any augmented or diminished interval are considered dissonances. With the fourth interval, the melodic interval is usually a consonance, and the harmonic interval is usually a dissonance.

3. What is the difference in size between a major interval and a minor interval with the same generic number (for example M6 and m6)?

The difference in size between a major interval and a minor interval with the same generic number is that the major interval is bigger by a half step.

4. What is the interval called that is one half step smaller than a minor interval? One half step larger than a major interval?

The interval that is one half step smaller than a minor interval is a diminished interval. The interval that is one half step larger than a major interval is an augmented interval.

5. What is the interval called that is one half step smaller that a perfect interval? One half step larger?

The interval one half step smaller than the perfect interval is a diminished interval. The interval that is one half step larger than the perfect interval is called the augmented interval.

6. Write an interval. What intervals can you think of that are enharmonically equivalent to it? What are the names of each of the different enharmonically equivalent intervals?

Diminished 5th – Augmented 4th

7. What qualities do intervals share that are in the same interval class?

The intervals that are in the same interval class share the same pair of pitches and the same musical distance between the pitches.