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This would make the chart consistent:

key of Cm: (Bb) Eb [Ab] (you have 7th, 3rd, 6th note)
Continuing same pattern with 7th, 3rd, 6th)
key of Gm: (F) Bb [Eb]
key of Dm: (C) F [Bb]
key of Am: (G) C [F]
key of Em: (D) G [C]
key of Bm: (A) D [G]
key of F#m: (E) A [D]
key of C#m: (B) E [A]
key of G#m: (F#) B [E]
key of Abm: (Gb)Cb [Fb]
key of Ebm: (Db) Gb [Cb]
key of Bbm: (Ab) Db [Gb]
key of Fm: (Eb) Ab [Db]

This is an interesting point, Gary. The challenge I think, is in containing such a universally expansive topic -- music -- within the scope of the analysis at hand.

In looking back at all the study threads -- at least the ones I have participated in, beginning with the Moonlight Sonata in mid August -- we have covered a tremendous amount of ground and not all pertaining to composition analysis. The very one we are looking at now -- Clementi Sonatine No. 5, Movement 1 -- has two full pages of discussion so far, and most to do with theory outside of composition analysis.

This is simply an observation. I for one have learned and am continuing to learn a tremendous amount. I am not sure how or if we want to change anything. At least we know where all the information resides. But, your point I think is a good one for consideration, Gary. Else, we start venturing in too many directions ... agreed.



Precisely, and I think we are all in agreement on that. Hence, why this is an important aspect of these analysis.

Yes, it would, but I have to intuitively figure out what “()” and “[]” mean. Furthermore, it puts the order of the notes in the scale in a theoretical order that makes no sense to me. Why 7 3 6? To what purpose? If a student is good enough at patterns to solve this little puzzle, that student is going to “get it” in just about any way we present it.

Here is what I see, but I can only work it out because I already know all the answers: Parentheses show degree 7. Brackets show degree 6. Degree 3 "is what it is". The parentheses show show a toggling 7, brackets show a toggling 6. It's all intellectual, in the wrong order. It's now how music works. I'm not even sure you did not make any mistakes. It's that artificial for me.

I would make a table, but I have NO idea how to do that here.

I would simply write the C scale, with the C minor scale directly below in the form that would follow the key signatures, thus major and natural minor.

I would join the 3rd, 6th, and 7th degrees with toggles. This is how I present parallel or tonic major/minor. I use the word parallel because I live in the US, but I also use trem tonic as the clearer term.

Until this concept is nailed down, I don't think we can explain key signatures. And until we explain key signatures, I don't think we can explain why music in minor keys does not always USE those key signatures, and why the 6th and 7th degrees came to be continually toggling between what they are in major and our purely natural minor for which key signatures came to be standardized for in the first place.

THEN I would explain that the 7th degree has to be raised about 50% of the time in tonal music because of the extreme importance of the dominant major chord or dominant 7 chord.

FINALLY I would explain how and why the harmonic minor scale came to be popular and where it appears most often (descending).

I want to clarify that this is not really my chart. I took what Richard wrote down, and made the other minor keys follow the same pattern as the first. I had to work out what (*) and [*] meant in the original, and could do so because I already understand how the music works. Since the minor keys were listed in a chart-like form, but according to different patterns, I wanted to give it consistency. I believe that I did previously write what (*) and [*] seemed to mean. I'm short of time and didn't want to explain it again.


I think I've done that a few times in the past, including your other points. This time round I simply wanted to make sense out of an existing chart. There are several ways of introducing it. I remember a few days you suggested a kind of generic system that covers all possibilities from the view of parallel majors and minors (C major, C minor). I liked the possibility of getting away from relative majors and minors (which is how I first learned it).

Originally I suggested that the circle of fifths can go hand in hand with what you hear and feel at the keyboard, especially if you are a by ear player already, and that exploration would lead to the discovery of a number of patterns. I assume those ideas were not considered useful since there was no response. That, rather than a reworking of the chart, would constitute my own ideas.


I'm rather sure that there are no mistakes. But I had to take a few steps in checking it since it's not intuitive, and I took the whole thing to the piano and played each minor scale to double check. Redoing the chart was a good exercise for me in strengthening what I already know, from a different angle.

Addendum:
This is how I understood the symbolism of (*) and [*] in Richard's chart, in case I didn't write it before.

Taking the example of Cm - (Bb) Eb [Ab]
The Bb and Ab both toggle in a Cm scale. All of the scales below are Cm scales.
C D Eb F G Ab Bb C
C D Eb F G Ab B C
C D Eb F G A B C

That is why the Ab (6th degree note) and Bb (7th degree note) were written with ( ) or [ ] around them = my guess.

I've found in useful, KS. I've printed the chart and I'm working with it as suggested. Sorry for not responding. Responding now. Yes useful, thanks.

Everything in fact I find is useful. The trouble I am having is in keeping up with it all. The pace of teaching and topic matter is beyond my capacity to absorb. So, I'm selective.

It is all good though. Judging by the amount of viewers on these threads, I'm certain I am not alone in this opinion.

Thanks, Greener. I really wasn't sure. Fwiw, I find it overwhelming from time to time too. I've only managed to look at a couple of the sonatinas.

Greener, the problem is that at any given moment we have people trying to master the same fundamentals with VASTLY different learning styles as well as very different levels of mastery.

Somewhere I’m sure you (or someone else) was writing something like this:

C7 F F7 Bb Bb7, etc.

THIS is the principle. It is not a circle, it is not a diagram, and it’s not a trick. In a mythical world all players would know all keys equally well. In fact, they would be born with this knowledge. It would be a given. Perfect world.

In THIS world people have their favorite keys, and you will notice an incredible difference in people who depend mostly on notation compared to ear players. Ear players have no idea why playing with all black keys would be harder than playing only the white ones, and from a physical and pure sound POV, they are right on the money. Eb minor with six flats? All these people know is that, BAM, you play all the black notes, stick in F and B and off you go improving your heart out. Comfortable for the hand.

The ear players don’t think, “Well, I have to NAME all these black keys, and I have to use alphabetical order to make sure I SPELL my scale right, and that means that my B is going to have to be a Cb, and my scale has to be Eb F Gb Ab Bb Cb Db Eb, if I’m playing natural minor, and oh, if I change that Cb to C because it sounds cool, I have to invent a new freakin’ NAME for the minor scale.”

Ear players are spared all that nonsense, because it belongs to the world of NOTATION.

Now, the people who make Holy Books out of scores and who never write music themselves, never play by ear, these people are locked into a passive world where everything is explained with rules, everything has to have a name, and so on. And because they are DEPENDENT on notation, they can’t PLAY anything written in C# minor or Db or Eb minor because they can’t read the notes on the page.

And that’s how people get stuck for YEARS in the dismal “easy classics” books that never get much beyond about 1800 and keep you imprisoned in a “white” world where only a few sharps and flats appear now and then.

Now, with that in mind, think about some really REALLY famous “classical” pieces:

Rachmaninov C# Minor Prelude
Chopin Minute Waltz, Db
The next Chopin Waltz, in C#m, with a middle section in Db.
Chopin Bb Minor Sonata (“Funeral”)
Debussy, Clair de lune, Db
Liszt Consolation, Db (the famous one)
Beethoven “Moonlight”, C# minor but second movement in Db
Gershwin 2nd Prelude, C# minor, middle section in F#.

Note that only C# minor does not use all the black keys, but that is only the KEY signature. Since degre 6 is one that is raised a huge amount of the time, in C# minor A# appears frequently.

Now, why are all these guys writing music in “hard keys”? Because these keys are NOT hard. They are child’s play to play in. They are only hard to read in, thanks to our very bizarre notation system.

So my point is that you are totally on the right track. Forget about circles. Use your EAR. Where does B7 want to go? E or Em. But how easy is it to change E or Em into E7? Simple. Where does it want to go? A something. And A7 wants to go to D.

Now, you can round and round the “circle” like a robot, playing all dom7 chords, but what about something like this?

G7 C A7 D E7 A F7 Bb G7 C.

And that is CONSERVATIVE. Try playing any V7 I, any key, then leap to ANY V7 in any key and got to ITS I.

The idea is that every V7 chord has a destination, and exploring that gives you the circle counter-clockwise. But every I has a V7 that GOES to it, and exploring THAT gives you the circle going clockwise.

If you start using your ear and your sense of patterns, the diagram will turn out to be as useful as cement boots.

I understand. But if there is one thing about all minor scales that is generally considered to be the “determiner” of minor, it is the b3. I would always emphasize that, in all keys. I teach melodic minor the “default” minor scale because to get there, you simply change one note, 3 to b3, and then you have something that is much closer to what music tends to do in any musical style that “spotlights” a dominant or dominant 7. When I have more time, I can actually make this idea crystal clear in CPE Bach’s Solfeggio where there is not ONE Ab or Bb in the main theme, although it is in C minor. Then, when that then is transposed first to G minor and later to F minor, the same thing happens. You have a G scale with B flatted, thus again melodic minor. In F minor, only Eb is changed. This is what melodic minor IS, major with only one note lowered.

That’s one place to start. To use lowering to get to natural minor is anything but simple, because you have to lower the maximum number of notes, b3, b6 and b7, but you can approach natural minor from a completely different perspective, as a major scale starting on a different degree of that scale (6) and so creating a different feel.

Basic example:

D E F# G A B C# D
B C# D E F# G A B

Melodic minor is easy although not diatonic or modal

Natural minor is easy AND it is BOTH diatonic and modal.

Should we define modal and diatonic???

Harmonic minor can be approached from either direction, starting with melodic but lowering 6, or starting with natural and raising 7.

The real point in all minor scales is that 6 and 7 are toggled.



We can’t dodge the idea of minors as being both relative and tonic (parallel). When a piece switches from Eb to C minor, it is logical to think of C minor as Eb, reordered because of the key signature, then realize that 6 and 7 will often be raised. But when Eb moves to Eb minor, then it is much more logical to simply say that G will become Gb but that C and D may remain as they are OR may be lowered, according to what is going on harmonically.

I know. I have one student who is weak in key signatures and who has a huge problem naming what kind of minor scale is going on. She is very weak in patterns. But I can always ask her “what goes to X”, meaning what is the V7 chord pushing towards any major or minor chord, and she nails that. I can say, “Where does this X7 want to go,” and she knows the answer. If I ask her to recite the circle of 5ths, she can’t do it, but when we run into CHORDS that are following it, she always gets it.

Now, note that we jumped from minor scales, how to make them or play them or recognize them to circle of 5ths. To me these things are totally UNRELATED while being learned, although musically they turn out to be connected in a million ways.

Turning back to minor, because I’m too tired to write anything else and have to be up early tomorrow, my presentation of scales goes far beyond separating major and minor. My idea is this:

C D Eb E F# F G Ab A Bb B C. That is almost a complete chromatic scale, and we are missing only C#/Db. Why do that?

Because we must at ALL times consider that 3 also toggles simply because in the key of C minor, C or C7 is VERY common to go to Fm, the chord. And it just gets STUPID to say, well, a C chord is not part of C minor. It is “secondary dominance” so not part of the minor. That is true, if you like that way of thinking.

If we take our most common chords, called primary, which are Cm, Fm and G, it is totally ordinary to have V7 chords to those chords going to them: C7 to Fm, D7 to G, G7 to Cm. E is in C7, F# is in D7, B is in G7. But it is also true that frequently F, not Fm, will be used as an alternate IV chord, so there is A. If you start off with natural minor, add raised 3, 6 and 7, then allow #4 for the D7 chord, you already have the above nearly complete chromatic scale. This also explains the SPELLING of the chromatic scale.

Finally Db appears in another chord, the Neapolitan, another stupid name, but you can see how easily you get to THAT chord by taking an Fm chord and raising the 5th.

F Ab C-->>F Ab Db.

So when you consider harmony, it gives you the complete chromatic scale and the default spelling for most common minor keys.

Example:

F G Ab Bb C Db Eb F, natural minor:

F G Ab *A* Bb *B* C Db *D* Eb *E* F, adding notes in dominants going to primary chords.
F *Gb* G Ab *A* Bb *B* C Db *D* Eb *E* F, completes is, note in Neapolitan..

THIS is the world Bach, Mozart and Beethoven lived in, a world of chromatic shifts, and people like Chopin, Wagner, Mahler, and so on just took the same idea to the max. And for a bonus, it explains the enharmonic choices they make in chromatic runs, according to key.

So much written overnight! I may have to start sleeping at work, or 'continue' as my boss would have it


What we're trying to do here is answer this question without bluntly saying go and learn the key signatures. We need a way to work while we're learning.

We have an F major triad. Looking at our circle of fifths we could be in F or any of the five adjacent keys, Bb or C major, G, D or A minor. We won't be in G maj or any further on the sharp side and we won't be Eb or any further on the flat side. We see from the grid (looking at it as notes now rather than chords) that if we're in Bb the E will be flattened. So we look at the E's to see if we're in Bb or F and the B's to see if we're in F or C. If we're in a minor key look for sharped sevenths, F#, C# or G# to suggest G, D or A minor. It's not too difficult to learn or work out what the sevenths are but using my three row ribbon rather than the two row circle, the seventh is a knight's move down and left on the third (diminished) row. In a minor key that might require a fourth row (yet another minor third down or three boxes left) but you can look for G, D and A on the top (major) row and look a knight's move down from there.

Sidenote: Using this grid is how I learned to associate notes in a scale with chords in a key (majors in the top row, sub-dom, tonic, dominant), minors in the second row (supertonic, sub-mediant, mediant) and diminished in the bottom row and noting the association of the diminished chord on the bottom left to the dominant seventh on the top right. I still find it easier, with remote keys, to find the flatted third (box above), or the sixth and seventh of a scale (box below and diagonally left) on this grid rather than 'knowing' the scale degrees. Whatever key we're in we're using one column to the left and one column to the right and if we ever move further we've usually modulated.

We have a key signature but it may be affected by local accidentals in the measure(s) being examined (combining to form what I laughingly call a 'prevailing' key sig). My list was not a good idea, especially being seen as a chart. Knowing key signatures is better and knowing that in minor the third gets flattened and the seventh get sharpened is all you need - not another chart.

We can also look at the bass and expect to see Bb, F and C if we're in F major or G, D and A if we're in D minor, etc. Again, we can see these in our circle of fifths.

The least amount of information you need is that which is enough to eliminate the five adjacent keys or reinforce the right one.

Without a V-I cadence the music may be deliberately ambiguous.
____________________


I know and appreciate what you're saying, Gary, but our prime objective here is not to analyse music - it was when we started on the Moonlight but it's not now - it is to look and see what weapons we're lacking in our analysing arsenal before we go back to such pieces as the Moonlight. The whole purpose of this thread, as far as I'm concerned, is to draw out these weaknesses and shore them up.

I wish I had the experience to do this more simply and the foresight to do this another way. Alas, I am not so gifted. I don't know where the next hole is going to be in the knowledge bucket.

On the face of it there are very few participants here but the number of views suggest we have many passive followers and while there aren't many asking the questions there are many benefitting from the answers and until they start objecting or falling away I don't see us as having strayed too far even though we've taken the scenic route.

Saying all these things in a number of ways, when we all explain our own understanding of a concept, is not creating confusion but seeing it from different viewpoints and it's doing two things: it is reinforcing the knowledge (and its importance), and it's increasing the possibility of the penny dropping for someone who may not be getting it.

You see things with a wealth of knowledge and experience, keystring is able to explain it to someone who may not yet have sufficient knowledge and PianoStudent88 is able to explain it to someone doesn't "hear" the concept.

I think we have a good formula here.

That makes me very happy, to hear it described that way. I sometimes feel incredibly stupid for not being able to hear most of this very clearly.

Today I was listening to a Baroque concerto on the radio and they came to the chords at the end of a phrase, and I thought "clearly minor." But if you play me chords in isolation, I have to think very hard to tell if they're major or minor, and I don't feel secure in my answer. If you play me a major scale first though, then the tonic minor chord played after that sounds clearly minor (and the tonic major chord sounds clearly major). However, a few months ago the Mozart Prague Symphony was on the radio, and I listened to the entire symphony thinking "clearly minor." I looked it up... and it's in D major.

That’s funny! Strangely, I do WAY more writing on the days when I am teaching. I thrive on being busy.

First of all, minor is always about 50 times harder than major, and for precisely the reasons we have all been talking about.

You HAVE to remember that in a minor key your IV chord can be either major or minor, and this is hugely important. I IV and V is the basis for just about all tonal music that is also harmonically simple.

So you have to do this, for a start:

F could be IV for either C or C minor
F can be V for either Bb or Bb minor.
F is I in F major


Yes, because F would be IIIm in D minor. But F s also IVm in A minor.

So you have:

1. F as V, in Bb

2. F as IV in C OR C minor

3. F as I in F

4. F as III in D minor

5. F as VI in A minor

6. F as VII in G

To me this feels hopelessly complicated, and it is not how I teach, but who knows. Maybe it will make sense to you!

This idea comes from the fact that you have major chords in a major key for I IV and V, so using C major as an example, C, F and G are very important. That’s obvious. And where they can go, these three major chords. But since ANY major chord can be I, IV or V in three different keys, you already have three answers.

Then in minor, again using C minor as an example, Eb, Ab and Bb are the major chords, exactly as they are in Eb major, so now III, IV and VII. Again, ANY of these chords can be III, IV or VI in some key.

Agreed. In my simple little world though, notation is a huge missing link and a void I am slowly trying to eliminate. I'm beginning to understand now, the complexity of notating something that is otherwise no issue to play.



I like this. Another perspective and weapon for arsenal.



... and Greener:
a) keeps us functioning as a cohesive and cooperative unit
b) asks only meaningful insightful questions at the most appropriate times with utmost of professionalism
c) ensures the unit functions strategically by achieving synergy from individual participants expertise
d) all of the above



Agree, and I for one, am very appreciative of the freely shared knowledge and expert insight these analysis threads are providing. And, quite certain that the many viewers are likewise equally appreciative.

I've finished my Cheerios now. Group hug everybody ...

Are we ready to move along with further analysis? Not sure if you saw my post from a couple of days back re: content ID for this movement, before we move along to the 'Air Suisse'. Here it is again.

There is an important principle here. Some lucky people just hear stuff. I don’t know how. It’s as if they start off at a place where most of us have to work to get to. To a large extent that is my story. But it is NOT the way the average person begins hearing things, and it’s not about where you start but where you GET to.

Most of my students can’t tell major from minor when chords are played in isolation. I can play random major and minor triads, and they simply guess. It’s about like flipping a coin and guessing heads or tails.

But if I play major and minor back and forth, toggling, starting with EITHER one, they will usually get it. It is the DIRECT comparison that starts a feeling of success: “Hey, I can DO this!”

The same thing will happen for any two “qualities”. If I toggle between minor and diminished triads, but keeping the same root, I will usually get the right answers. Each student has a different experience, but typical would be that minor sounds dark or heavy or serious, but it could be a final chord. A diminished chord is heard as something different, perhaps as something that is creepier or more “up in the air”.

But this is EXACTLY the point I was trying to make. There are two extremes:

1) People who play by ear, and very well, who have little or no knowledge of notation.
2) People who can read just about anything in the universe but who have rarely if ever tried to play anything strictly by ear.

Obviously complete musicians are comfortable doing BOTH, but that can easily never happen if said musicians are not taught to read fluenty AND are not encouraged to experiment with pure sound away from notation.

Do you see the problem for teachers in this environment? We have people who have problems hearing the difference between two chords but who will never miss them when reading, then we have others who will instantly hear just about any chord as what it is but who will not be able to read the same chord.

Teaching these two very opposite kinds of students implies a totally DIFFERENT approach, and essentially it is an attempt at balance. When I am teaching I stress reading hugely, from day one, but I also stress chords from day one, and playing with them. I teach scales entirely by rote then ask students to experiment. Then we talk about each scale and each chord that we have learned when it appears in music we are learning.

First of all, why FIVE adjacent keys? Let’s think this through:

F belongs in Bb, C and of course to F itself. That’s three places it is very comfortable.

As I explained it belongs to A minor, D minor and G minor but it also belongs to C minor, since in minor a IV chord can also be major.

Richard, I am not debating or correcting. I’m not sure my way of thinking is better. It may be worse.

But I am merely considering where major chord are most likely to appear in an any major or minor key, using the degree (such as I IV and V), then considering that ANY of these chords can be I IV or V in any OTHER key. Then I do the same thing in minor. For instance, in C minor Eb F Ab and Bb can all be major.

I don’t know if you grew up watching TV shows, some of them really HORRIBLE, you had to absorb the sounds of the typical “cowboy” themes, and there is an idiom there that is very common. Think only of the “Marlboro Man” theme, which came from “The Magnificent Seven”. Are we going to throw out this kind of music and stick only to sonatinas?

That’s what I mean when I talk about the “Baroque/Classical Musical Ghetto”. We start out with the assumption that anything outside of what Clementi or Mozart is not important, or too difficult. But this musical idiom, bVII to I, has been common for a very long time, and if we don’t consider it, we will also be lost when music goes Bb to G to C in the key of C major.

Or F to D to G in the key of G major

I may be mucking things up here. I may be jumping to hard things too soon, and I hope Greener and others will jump in and tell me if I am introducing confusing things!

Thinking more of major and minor and hearing: we're singing the Cantique de Jean Racine by Gabriel Fauré in chorus this fall. It's written in D major, or so it would appear (five flats, Db major chord at start and end). But it doesn't sound major at all to me. I'm trying to analyze it to try to understand how he achieves that effect.

Thinking about applying that to our sonatina analysis, it tells me that I need the paper analysis because I can't reliably hear if something is major or minor. On the other hand, it suggests that starting by listening might be exactly right, to collect up my aural impressions of a piece, and then using those to investigate the score. Then investigate the whole score. Then I'd end up with a set of categories, places where I hear interest or ordinariness, combined with places where the score suggests interest or ordinariness.

The most interesting of those categories for me, I think, is places where I hear something interesting and then I can find out from the score how the composer achieved it. This is rather a switch for me, because I used to not much care about the sound and only care about the patterns I could find on paper. In my music theory course I always felt incompetent at the sound part. We would be told what to listen for -- for example, the second part is in the relative minor, or the chords are alternating V7 I over and over -- and I could never understand what those kinds of things sounded like. But starting from a learner-centered approach, where I start with what I can hear and then investigate it, makes me feel much more successful: it allows me to come to terms with listening at my own pace and in my own terms.

I don't usually identify a key (or local tonality) from a single chord in isolation. Sure, I can play the game of "in how many scales does the F major chord appear naturally?" (looking among the major and three constructed minor scales). But in practice, I'm using other chords, contextual clues, or the set if sharps and flats.

Other chords, usually V I or VIIdim I relations tip me off:

If I find lots of C7 and F, I expect I'm in F major. V7 I.

If I find lots of F and Bb, I expect Bb major. V I

F and Bbm, I expect Bb minor. V Im.

F and Dm, although I know "bIII, major", in theory, I don't usually recognize the key of D minor from this pair of chords. It takes either A or C#dim for me to quickly arrive at Dm.

Context:

If the piece ends on F, then I expect it's in F major.

If a passage has a lot of F Dm F Dm F Dm I may eventually start to wonder if it's in D minor (or F major), and start looking for other clues to confirm that.

Pattern of sharps and flats:

If I find both sharps and flats mixed up, I suspect a minor key, and use what I know about minor key signatures and leading tones to figure it out. I'm thinking some of what Gary has written about key may help me to figure this out more easily. For example, I always find it very difficult to figure out that the development of Clementi Sonatina #1, 1st movement, starts in C minor (and I can't remember if it stays in C minor). Gary's method, which I think involves zeroing in on the Eb and considering that it may be the flat third degree, may help me.

When I ever manage to get back to the Clementi scores, I'll look through them to give some examples of these ideas in action.

Major miscommunication!

I never use “analyze” in a narrow way, so it’s probably the wrong word. I simply meant that we are covering many different concepts, and it might be good to open additional threads in the future as a place to cover certain things in more depth. But if this is working as it, then I agree that we should continue: “If it ain’t broke, don’t fix it!”

I could not do a better job. If I make suggestions, or find possible holes, that’s because I am a bit on the outside, looking in. There are several factors that make me feel very unsure here:

1) We are dealing with people with SO many different backgrounds that it is a bit like teaching a large class where anyone can sign up, regardless of what they do or do not know.

2) We have only words. That is infinitely more difficult than teaching people we can see and interact with in other ways.

3) Some of the subjects we are covering here I do not normally cover very often with students, primarily because of lack of time. So trying to explain things here should help me teach better in “real life”.

This is why we want you here, Gary!

Yes, let's think things through, indeed!

F major by itself implies that we could be in any number of different keys. Any number of keys could have an F, A or C in it. Clearly we need to investigate further. And I simply overlooked that. If it were F major in Bb or C minor there will be other clues such as Db, Eb, or a temporarily sharpened Ab (= A natural).

It could also be the flattened supertonic in E major. Or a temporary chromaticism in Gb major/Eb minor.

We will not come across an F major chord without it's occuring in context. So as well as the chord itself we must look at its context. After the chord itself look at the key signature and consider how it might be affected by extant accidentals. Look at the bass, the foundation of music.

We can't determine key from one thing alone. We need to keep adding clues until we can isolate one area or settle for ambiguity. We can expect that in the exposition of a sonatina it will be an easy matter. In the middle of a Wagnerian opera or a jazz improv, it may not be so straightforward.

So, returning to the original question of how much information is required to determine key, we conclude that there must be enough information from the chord and it's context to either establish the key or accept tonic ambiguity.

I see our paper wizard has already covered context.

Thank you, Gary, for your clarification and encouragement.