music_theory:dimensions_of_tonal_music

The Dimensions of Tonal Music

512 Hz – Seventh Overtone / Eighth Partial
448 Hz – Sixth Overtone / Seventh Partial

384 Hz – Fifth Overtone / Sixth Partial
320 Hz – Fourth Overtone / Fifth Partial

256 Hz – Third Overtone / Fourth Partial
192 Hz – Second Overtone / Third Partial

128 Hz – First Overtone / Second Partial
64 Hz – Fundamental / First Partial

The optimal vertical element – the most stable and “natural” harmonic sonority.

Preference Interval between bass and any upper voice Interval between any upper voices Harmonic Quality Doubling in four parts (R = Root, 3 = Third, 5 = Fifth) Spacing
Most preferred Perfect Octave Perfect Octave Major Triad RR53 Larger intervals between lower voices; smaller intervals between higher voices; no more than an 8ve between S-A and A-T
Perfect Fifth Fifth / Fourth Minor Triad
Major Third Major Third, Minor Third
Minor Third Major Sixth, Minor Sixth
OK, but less preferred Major and Minor Sixth Diminished Triad R553, RRR3
R533, RR33
Even less preferred Sevenths Sevenths Seventh Chord RR55, R555, RRR5, R333 S-A or A-T greater than 8ve; T-B relatively low in their ranges and a 3rd apart
Seconds Seconds Augmented Triad, Extended Tertian Harmony (9ths, 11ths, etc)
Fourths, Augmented and Diminished intervals Augmented and Diminished intervals

The optimal horizontal element – The most perceptually coherent line.

Preference Generic Interval Size Scale Quality of Interval Other
Most preferred Second Within prevailing diatonic space Perfect, Major, Minor Interesting shape (such as “arch”); Maintains inertia; Goal-oriented; Leap in one direction followed by a step in opposite direction
Common Tone (Octave)
OK, but less preferred Third Diminished
Fourth, Fifth
Even less preferred Larger leaps (6ths, 7ths) Outside prevailing diatonic space Augmented Difficult to sing, Monotonous

The optimal interaction between two lines – each line remains independent and perceptually distinct (soprano and bass counterpoint most important in textures of three or more voices).

Preference Relationship Between Lines Lines in Close Proximity
Most preferred Contrary motion No voice crossing; no lines in unison
Similar / Oblique motion Lines move by contrary motion into or out of a unison
Parallel Motion (of intervals other than 5ths and 8ths)
OK, but less preferred Similar (Unequal) Fifths (d5 to P5, or vice versa) Lines move by similar motion into or out of unison
Even less preferred Parallel perfect 5ths and 8ths Voice crossing

A Simple Theory of Voice Leading

Voice leading in tonal music represents the best possible compromise among these three competing priorities: optimal harmony, optimal melodic motion, and optimal interaction between melodic lines. Each of these three priorities is as good as the other priorities will allow.
  • music_theory/dimensions_of_tonal_music.txt
  • Last modified: 2017/07/13 17:18
  • by brian