fifth
Let an agent handle the musical fifth by type, sound, notation, tuning and use in harmony, and separate other senses of fifth.
Research draft, second pass
A second pass drafted this model: the structure a model of this thing needs, and what is known about it in the world. The line under this one says how the second half was obtained - researched against sources, or recalled without web access, in which case nothing here was read anywhere and every claim is a lead to verify. Unreviewed either way.
written by Claude from model knowledge without web access - no source was read, every claim is a lead to verify
Researched by: Claude
Purpose and description
Let an agent handle the musical fifth by type, sound, notation, tuning and use in harmony, and separate other senses of fifth.
In music, the interval spanning five diatonic scale degrees; the perfect fifth (seven semitones, frequency ratio about 3:2) is fundamental to harmony and tuning, with diminished and augmented fifths as variants.
What it is for: Harmony, tuning and composition.
It can be identify and name fifths; tune instruments by fifths; explain the circle of fifths; recognise fifths by ear.
Distinguishing features
Five scale degrees apart
Perfect fifth is very consonant
Basis of the circle of fifths
Used in tuning string instruments
What it looks like
Heard as a stable, open sound; written as notes five letter names apart.
Physical character
perfect fifth ratio: about 3:2 - just intonation
equal-tempered perfect fifth: 700 cents
How it is recognised
Seven semitones for a perfect fifth
Circle of fifths diagrams
Fifth as an ordinal or a fraction is a different sense
Related models
is a kind of - category
is used in - practice
is related to - tool
is confused with - another sense
In practice
Families and kinds
perfect fifth
diminished fifth
augmented fifth
power chords (related)
Failure modes and hazards
Confusing interval quality
Confusing senses
Also called
Where this came from
wikidata · CC0 1.0
Also registered as vr.tr.fifth-communication
Drafted structure
Bundle to layer to finding to question, as the second pass will find it: 4 bundles · 8 layers · 8 findings · 16 questions.
Interval Which fifth.
Quality matters.
Quality
Perfect, diminished.
Quality
Interval quality.
- Is it a perfect, diminished or augmented fifth? definition
- How many semitones? measurement
Notation
Notes.
Notation
Notation.
- Which notes form this fifth? definition
- How is it spelled correctly? definition
Harmony Use.
Fifths structure harmony.
Circle
Circle of fifths.
Circle
Circle of fifths.
- How does the circle of fifths relate keys? definition
- How is it used in composition? action
Voice leading
Parallel fifths.
Voice leading
Voice leading.
- Why are parallel fifths avoided in some styles? definition
- In which styles are they used freely? provenance
Tuning Instruments.
Tuning uses fifths.
Instruments
Strings.
Instruments
Tuning instruments.
- How are instruments such as the violin tuned in fifths? action
- Which reference pitch is used? provenance
Temperament
Systems.
Temperament
Temperament.
- How does the fifth differ between just and equal temperament? measurement
- Why does it matter? definition
Learning Ear training.
Ears can be trained.
Ear
Recognition.
Ear
Ear training.
- How can the fifth be recognised by ear? action
- Which reference songs help? provenance
Senses
Disambiguation.
Senses
Other senses.
- Is fifth as an ordinal, fraction or bottle size meant? boundary
- Which entry fits? action
What the second pass must settle
- Should each fifth type be a separate entry?
- How should tuning systems be linked?
- How should other senses be split off?