We all know about major and minor keys ... but what is the function of the MINOR keys?

It was in re-reading the gobbledegook of my antiquated Harmony Bible, that the thought occurred ... why no function explanation ... just a case of "shut up and row"!.

Quote
"The minor key generally has a sadder, heavier effect, though not always.
A bright rhythm or a quick pace can modify the effect.
Tell the pupil to listen particularly to the 3rd of the scale (what a hope!!) ...
and decide whether it is "me or maw", as this is the main distinguishing feature."

But WHY? ... thanks for your thoughts chaps ... please keep it tight.

I could ask the same thing about all those other scales (modes?) I can't even name. Why?

Scales (keys) came along some millions of years after songs. They're kinda out of touch.

Why does the minor key have to have a function?

What's the function of the major key?

Major and minor keys are both nothing but the surviving detritus of the ecclesiatical modes that were the organizing feature of music in the medieval and early renaissance periods. And those modes were nothing but seven different ways of using the seven-notes between and octave that were available at the time (and maybe B-flat, but that's a different story).

Why the current major and minor scales are all that survive of the modal tradition (OK, except in jazz), I'm not sure. I think that even in the renaissance era certain modes were not widely used, and I'm inclined to think that composers just came to a sort of working consensus that one or two modes would do, particular once chromaticism became established.

As for why minor keys sound `sad' or `serious', I think that's just cultural conditioning. We're exposed from birth to an association between graveness and a minor key. I'd be interested to know if there were a more scientific explanation.

There were a couple of long threads on this topic (well, loosely anyway ) on the Pianists' Corner board in the past year and no such scientific explanation was forthcoming, except mentions of some experiment done with some remote people in Africa. The experiment raised far more questions to my mind than it answered.

don't know how spot on I am with this, but
natural harmonics produce a strong major third, and harmonics are the vibrations of nature, available to all cultures/times/places, so it would seem that in the west, we have associated that natural sound with "happy", i.e. made it a positive. this goes back to the greeks who had a dominant relationship with nature. they could manipulate their environment to their liking, thus natural sound would have positive connotations for them. for cultures and civilizations that exercised less control over their environment, these natural pitch vibrations may have foreboding or menacing connotations: they represent the unknown, uncontrollable, unexplainable, etc. Therefore, that major third sound may have a negative connotation to the ear and their culture may produce more minor music and associate that with positive b/c it's a step away from nature.

hmm... interesting question.

more on this...
i don't think the modes are antiquated or outdated. it's like gravity - yeah it's an old discovery, but we're still using it right? still relevant.
i think the same goes for the modes. modern composers experiment with deconstructing our emotional associations with modes, but to no avail. the modes are not just changing the 7th degree and so on, but were created, or rather discovered, as expressions of mathematics and natural balance. i think the ancients understood the mathematics behind music much better than we do today.

Wasn't there a bit more to it than that? And was it seven notes?

Well, yes, there was a bit more to it -- about 400 years' worth, I guess. That was just my two-line summary

As for seven notes, the Gregorian modes that became dominant (no pun intended) in ~10th century were based on the seven-note scale, which is essentially the same diatonic scale we now use, except that the temperament would have been different. But the B was flattened in certain modes.

Of course there were other modes, and it's not entirely clear how the Gregorian modes are related to ancient Greek musical modes, if at all, even though similar terminology was used.

That's a fair point: in just or pythogorean tuning, two notes sounding a major third apart have a harmonic in common much closer to the fundamental than two notes a minor third apart (at one time I could have remembered exactly how close, but I've forgotten). This fact, after all, is what Helmholtz claimed was the basis for consonance. So in Helmoltzian terms, a major third is (much) more consant than in minor third.

But the problem with this argument is that, with equal temperament, neither the major nor the minor third is `pure'. So I rather suspect that both major and minor thirds are still only recognized for cultural reasons.

Trying to untangle this a bit:

Gregorian chant is not a mode. It is one of the chant dialects (Ambrosian, Gregorian, Old Roman, Byzantine) - the chants were in modes. There were hexachords (d'Arezzi?) of six notes starting on either F, C or G but through a kind of overlap system called mutation you could get more than six - it ends up being like our modern 7-note scale. The F "soft hexachord" has the flat B, the C "natural hexachord" has no B of any kind, and the G "hard hexachord" had natural B. These are not modes. Modes are "like" starting the C major scale from C to C, D to D, E to E etc. We end up with a particular sequence of intervals which are thought to create these moods or character being discussed here.

Going further back, the Greeks had modes in tetrachord arrangements, with a P4 and two notes in between. You sort of ended up with something similar to the above: that is, different fixed sets of intervals along which your music moved. It was believed that these modes affected our character or persona, along with rhythmic patterns, which did the same. The part that we don't have anymore are the different temperaments of the three species.

Originally I was responding to this:

There was the underlying idea of each mode creating a certain character, so maybe it was not that arbitrary or random. I think that for ideological (religious) reasons those are the notes that were chosen, in the same way that rhythms that were multiples of three were preferred.

That's what I have managed to understand so far.

Equal temperament is how keyboard instruments are tuned, but other instruments use different tuning even in traditional Western music. To those of us who do play other instruments, pianos can sound perpetually slightly out of tune.

By Gregorian modes I mean that system of modes that was developed alongside the tradition of Gregorian chant and which may, or may not, derive from more ancient modal traditions. There's a complication of terminology here: it's not clear when authors like Boethius use the word `modus' that they have in mind the same notion of mode that arose in the 9th-10th century.

Anyhow, this is all very interesting and I'm happy to continue a discussion of the history of ecclesiastical modes, but I'm not sure how it relates to the original topic