User:Moremajorthanmajor/United Kingdom of Musical Instruments

Notice: Even though this topic is from a fictional world based on real types of musical instruments which have human lives, no terminology given here is to confused with legitimate proposals of how to talk about any musical practice in the real world.

The musical system of the modern United Kingdom of Musical Instruments fundamentally obeys the concepts of conventional human musical systems to the whole depth of musical history. That is, it is ideally based on Just Intonation and thus normally prioritizes the perfect consonances of the 3-limit, followed closely by the remaining true relations of the ideally consonant thirds and sixths and the commonly dissonant steps/seconds and sevenths. False relations are normally more important for how they are averted or masked than for compositions which proceed into them.

Where the instruments differ is in their underlying system(s) of functionality though their systems of functionality with the most native documentation are also originally Eurasian and North African. The globally most popular system of functionality is that which fully crystallized in Medieval Western Europe. There is no single standard name for this system, which is derived from the real-world music history of very late medieval and later pre-classical theorists, who used terms like musica mensurata ("measured music") or cantus mensurabilis ("measurable song") to refer to the rhythmically defined polyphonic music of their age, as opposed to musica plana or musica choralis, i.e., Gregorian plainchant which is happening alongside this system in-universe. The most common terms for this system have changed across its history from the medieval chordon conjugans (“conjugating chord”) to the modern “conjugable tone” and its various translations, as opposed to the presumed “non-conjugating” octaves underlying both Gregorian plainchant and the rhythmically defined polyphonic music. The main defining feature of compositions in this tradition are the progressions from one “chord” to another by changing the balance of perfect fourths and perfect fifths in the frame interval of the simple gamut which would traditionally signal the start of a new piece of a sequence. The traditional goal of these “chord progressions” would be a “chord” within one step of the octave on the circle of fifths to give a sense of finality to the last piece of a sequence. The circle of fifths is often grouped into the three parts of the “regular conjugation”.

Distance from octave	Class	Name	Desired (sub)harmonic	Regular conjugation
6 fifths	Strongest, fortissimus	Fa♯	*11	Augmented eleventh, eighteenth (technically)
5 fifths		Si	15	Major seventh, fourteenth
4 fifths		Mi	5	Major tenth, seventeenth
3 fifths		La	27 (technically)	Major sixth, thirteenth
2 fifths	Stronger, fortior	Re	9	Major ninth, sixteenth
1 fifth	Strong, fortis	Sol	3	Perfect twelfth
0	Natural, naturalis	Ut > Do	(2)	Perfect octave, fifteenth
1 fourth	Weak, lenis	Fa, originally superparticularis	43 (technically)	Perfect eleventh, eighteenth
2 fourths	Weaker, lenior	Fa superbipartiens > Si♭	7	Minor seventh, fourteenth
3 fourths	Weakest, lenissimus	Fa supertripartiens > Mi♭	19 (technically)	Minor tenth, seventeenth
4 fourths		Fa superquadripartiens > La♭	1/5 > 13	Minor sixth, thirteenth
5 fourths		Fa superquinquipartiens > Re♭	17	Minor ninth, sixteenth
6 fourths		Sol♭	*11	Diminished twelfth

Major is considered as comparable to Sol as minor is to Fa, but Sol superparticularis and Sol superpartiens never saw as widespread usage as Fa superparticularis and Fa superpartiens before the conversion of the latter to flats. At that time, it was also widespread, but not absolute, that only the true relations were considered within the bounds of the modal system.