t 4th, perfect 5th, 6th, octave) are allowed. In general, no dissonant leaps&emdash;this means no seventh leaps. OK to leap down diminished fifth in major or minor (from 4th to 7th scale degree) or diminished fourth in minor (from 3rd to 7th scale degree) if next note is a step up.
Leaps by fifth will dominate the bass line, especially at first; the soprano should use leaps sparingly, to create an interesting contour. Inner voices should move primarily by step; avoid leaps larger than a fourth or fifth in inner voices.
General guideline: a leap followed be a step in the opposite direction is always effective. The larger the leap, the more this becomes essential. Leaps of 3rd, perfect 4th or perfect 5th are often followed by a step in the same direction; leaps of a 6th or octave always require a change of direction in the line, usually by step.
Consecutive leaps in the same direction must outline a major or minor triad.
Movement from one chord to another should usually involve a mixture of parallel, similar, contrary and oblique motion. Avoid all four voices moving in the same direction, especially by leap.
Consecutive fifths and octaves
If there is the interval of an octave or perfect fifth between 2 voices in a chord, make sure that same interval does not recur between the same 2 voices in the next chord.
Movement into an octave or perfect fifth in similar motion
If the interval between soprano and bass is an octave or perfect fifth, then make sure that if the two voices move in similar motion to the octave or fifth, then the soprano moves by step.
Tenor and alto may cross occasionally if the crossing produces better melodic lines and/or makes the voice leading smoother in these parts. Do not cross bass with tenor or soprano with alto.
Avoid overlapping voices; it is usually preferable to change from closed to open or open to closed spacing from one chord to the next.
Half Steps in Scales
Half steps call for special care.
The half step between 7 and 8 in major and with the raised 7th degree in minor is especially sensitive point melodically. In general, the leading tone should proceed to the tonic, especially in minor, unless there is a reason&emdash;which might well be to get a complete chord by making the leading tone jump down to a chord tone.
Other sensitive points are the half step between the 4th and 3rd scale degrees in major and between the 6th and 5th scale degrees in (natural) minor. These are less compelling than the leading tone, but making progressions which use their potential to move strongly by half step from above to the 3rd scale degree in major and the 5th degree in minor will lead you to many beautiful progressions.
It is especially important to respect these tendencies in the soprano voice; use will to give the melody a very strong sense of direction.
The Tritone in the V7 chord
Major and minor with raised 7th scale degree have a tritone between the 4th and 7th scale degrees ; this interval appears in the V7 chord. When possible, resolve it so both the 7th degree and the 4th degree move by half step in contrary motion; this makes a very strong resolution.
Dissonant tones in chords
The 7th in the dominant seventh (the 4th degree of the scale) differs from every other chord tone; it produces two dissonant intervals in the V7 chord&emdash;a minor seventh with the root of the chord (scale degrees 4 and 5, a whole step apart) and a tritone with the 3rd of the chord (scale degrees 4 and 7). This dissonant tone MUST resolve down by step to the third of a tonic chord, wherever it appears in the chord; it may NOT move up by step. (The 7th can, however, be moved from one voice to another, by extending the V7 chord, before it resolves; this produces a very special effect.)
Function of the Soprano
The soprano carries the main melodic line. It needs to have an interesting contour. It is especially important to resolve tendency tones&emdash;leading tone&emdash;in the soprano voice, and to create melodic drive toward the final cadence.
Function of the Bass
The bass voice defines the succession of chords; the bass 