Chord Sequences ~ Major or Minor Key?

shanejunkin

Hi, I've always been confused about the diffference between major and minor keys with respect to chord sequences in particular, and maybe any sequence.

If you consider the key or C, there are no sharp or flat notes. So, consider a piece of music with a number of chords, all built with no sharps or flats, i.e. chords from the key of C. How do you know whether the piece of music is in C major or A minor? As A minor also has no sharps and flats?

Is whether the key is major (C in this case) or minor (A in this case) decided by how the piece of music finishes up i.e. the cadence that is used?

Or is it down to what chord the piece starts on, i.e. if it starts on A minor it's in A minor (I actually don't think this is correct at all, but a lot of people believe that to be the case)

Can anyone help me?

Rigsby

I'm no expert on theory, but here's my opinion for what it's worth. I think if you look at modes, things might make more sence. From the C major scale you can get different modes (in esscence other scales). These modes can contain flats or sharps. You can make chords from these modes. I'm probably not explaining this very well, so take a look at the link below and hopefully it should throw some light on things. It's a bass guitar site but that should n't make much difference.




http://wheatsbassbook.org/chapter_select.php?chapter=010


EDIT : You might also like to look at the "Modes" thread on this forum.

ogy

the starting chord is not really reliable, but often the final chord gives away the key. also A minor will often have accidentals on Gsharp or Fsharp, owing to the harmonic minor and melodic minor scales. so in A minor you usually get an E major, but in C major you get E minor.

however both of these things or just fairly reliable rules of thumb, not absolutes.

what gives a key away is the importance placed on certain chords and notes, how the which chords are used to create resolutions determine the key, and the melodies wil be based around scales of c major or a minor (while both scales have the same key signature, the importance of the tonic note will be emphasized differently).

Stompbox

Rigsby, when you construct other modes from C Major those scales will contain the exact same notes as C major scale? I think that's correct.

I wouldn't really agree with Ogy either, I've played an E Major while playing in C and it sounds fantastic! Id tend agree with the emphasis on the tonic note.

Then again, I could be completely wrong!

ogy

i was talking classical theory, in a c major scale, E is minor, cos theres no G sharp in the C major scale. it doesn't mean it won't sound good:)
you can either view the E major sounding good as breaking the rules cos it works, or the more technical explanation for it is that your doing a little key change in the middle of your chord progression. like if you go C MAJOR, E MAJOR, A MINOR, F major, G Major, C Major. the E major works because its kinda like a little perfect cadence in the key of A minor before switching back to C major. I think thats called a tonicisation:)

shatners basoon

Emphasis on the tonic is important. Usually you can tell just by the feel or the tone of the composition though. Modes wise it'd be the same notes alright but most likely different emphasis in terms of the approach to them (again directed around the feel of the key). For the most part though its not a particularily important, in fact its better to know the similarities than the differences if you're interested in chord substitutions etc.

shanejunkin

OK guys, so what we’re saying is that the notes used to build all of the chords in a chord sequence will tell us that the key is in either x major or y minor (e.g. if a sequence with no sharps or flats the key is either C major or A minor (assuming no accidentals)). Then to decide on whether it is the major or minor “option” we must consider the actual emphasis on a certain chord. Such emphasis dictates whether the key is the associated (to the notes used) major or minor key.

From that if we consider the intro/verse of Red Hot Chili’s Dani California of Am, Gmaj, Dm and Am we can conclude that it is in A minor (http://www.youtube.com/watch?v=LaRXXwycwco ). Considering the notes used to build all of those chords the key could be either C maj or Am (no sharps or flats). Then looking at the emphasis of chords’ sequence we can conclude that it is in Am rather than Cmaj because the piece starts and ends with the Am chord, so Am must be the tonic?

What confuses me is when the tonic choices, as dictated by the notes (in this example C or A because there’s no sharps or flats), are not included in the chord progression. For example a piece with no sharps or flats that doesn’t have a Cmaj or Am chord in it.

I can’t think of a good example, but just play a chord sequence of Dm, Em, F and G. Is there anyway to decide whether that’s in Am or Cmaj? If there’s not, does it just mean that it’s a kind of non descript, weak chord sequence, basically an objective argument that it’s a poor piece of music?

Rigsby

Sweet wrote: »

Rigsby, when you construct other modes from C Major those scales will contain the exact same notes as C major scale? I think that's correct.

Thats correct. It's just that you are starting and ending on a different note of the major scale depending on the mode.


CDEFGAB(C) = Major (Ionian) mode. If you start on the 2nd note (D) this gives you DEFGABC which is the Dorian mode.


Start on 3rd note E = Phrygian Mode ( EFGABCD )...... and so on through the seven modes.

shanejunkin

OK, that is a good explanation as to where different scale modes come from. Thanks, I never spotted how to rectify them with key signitures, for example that the D scale in the Dorian mode is actually in the key of C.

However, from your knowledge of modes etc. can you explain to me what key the chord sequence of Dm, Em, F and G is in? Is it in Am or Cmaj?

Maybe it's irrelevant, but I'm sure there has to be a rule to dictate which it's in, it sounds like a correct chord sequence (not a great one, but there doesn't seem to be any out of place sounding chords)

So, is it Am or Cmaj?

Rigsby

shanejunkin wrote: »

OK, that is a good explanation as to where different scale modes come from. Thanks, I never spotted how to rectify them with key signitures, for example that the D scale in the Dorian mode is actually in the key of C.

However, from your knowledge of modes etc. can you explain to me what key the chord sequence of Dm, Em, F and G is in? Is it in Am or Cmaj?

Maybe it's irrelevant, but I'm sure there has to be a rule to dictate which it's in, it sounds like a correct chord sequence (not a great one, but there doesn't seem to be any out of place sounding chords)

So, is it Am or Cmaj?

http://www.myguitarworkshop.com/Theory/what-key-is-a-song-in/what-key-is-a-song-in.htm



Hope that is of some help.

kawaii

shanejunkin wrote: »

However, from your knowledge of modes etc. can you explain to me what key the chord sequence of Dm, Em, F and G is in? Is it in Am or Cmaj?

That would more likely be in the key of C major. Generally, the dominant chord (the chord whos root is a fifth above the tonic chords) is a major chord eg: in C major the dominant chord is G major.

In minor keys the third of the dominant is usually sharpened, as this strengthens it's resolution to the tonic, as the third of the dominant chord is the leading note of the key (eg: B in the key of C minor, G# in the key of A minor).

If that chord sequence was in the key of A minor, the E chord would tend to be a major, and it would almost certainly resolve to the tonic (A minor). A progression where the dominant chord moves to a chord other than the tonic is generally regarded as weak.

18AD

shanejunkin wrote: »

However, from your knowledge of modes etc. can you explain to me what key the chord sequence of Dm, Em, F and G is in? Is it in Am or Cmaj?

It doesn't have to be in either of those.

DFA
EGB
FAC
GBD

Recurring notes are F, A, G and B.
Aminor is a more likely candidate since it's a repeated note.

The Gmajor will resolve nicely to Cmajor, but if you're not going there then it's kind of irrelevant.

If it's a repeating progression I think it'll sound as if it's in Gmajor (mixolydian mode).

Good luck.
AD.

shanejunkin

Hi Kawaii,

For it to have an Emaj in it, to be in Am as you suggest, that would mean the chord sequence would no longer have no sharps and flats as Emaj contains a G# note?

shanejunkin

Hi 18AD,

Thanks for your help. However, I don't understand how that chord sequence will sound like it's in Gmaj as in Gmaj you don't have a Dm (it Dmaj), Em is OK, you don't have an Fmaj either (it's an F#Aug) and the Gmaj is OK. So there are two chords out of four that aren't in Gmaj.

I'm not saying you're wrong, I'm just confused. I suppose just adding a Cmaj at the end would clearly plant it in the major key, but I was always curious about chord sequences that don't include the tonic as suggested by the key signature (the notes used).

Could this sequence be described as another key with accidentals maybe?

18AD

shanejunkin wrote: »

Could this sequence be described as another key with accidentals maybe?

I think that would just confuse things further. The notes used are all in Cmajor so there's no need to do this. But you can if you want!
Gmajor with an accidental on the F.

Otherwise, I was suggesting that if it's resolving to Gmajor that it would be in Gmixolydian mode. The chord is still Gmajor regardless and your key signature can remain like that of Cmajor.

The chord progression can be interpretted in different ways. It's not a very obvious one. It could be in F lydian. I think it depends what you have going on around it.

Good luck.
AD.

kawaii

shanejunkin wrote: »

Hi Kawaii,

For it to have an Emaj in it, to be in Am as you suggest, that would mean the chord sequence would no longer have no sharps and flats as Emaj contains a G# note?

It's is still the key of a minor though. The G# is an accidental, but the key signature is still without sharps (a minor).

Indeed music would be very dull without accidentals (and modulations...).

ogy

OK, that is a good explanation as to where different scale modes come from. Thanks, I never spotted how to rectify them with key signitures, for example that the D scale in the Dorian mode is actually in the key of C.

However, from your knowledge of modes etc. can you explain to me what key the chord sequence of Dm, Em, F and G is in? Is it in Am or Cmaj?

ok what you realised there is important, but you also missed the point slightly.

The different scale modes were around BEFORE the whole major minor distinction. Major scales and minor scales are just the two most commonly used scales in Western Classical Music.

From a modal perspective C Major and A minor are just other modes. C major scale is the Ionian mode. A minor scale is the Aeolian mode.

Supposing your chord sequence is emphasising D as the tonic/D minor as the root chord, then its in the Dorian mode. This shares the key signature of C Major (Ionian) and A Minor (Aeolian), but its neither, its another mode.

For any given key signature you have 7 modes. The Ionian one is that one we usually call major for that key sig, and the aeolian one is the one we usually call minor for that key signature.

The whole thing of accidentals in minor keys are kinda corruptions of the aeolian scale. Classical composers liked that the tonic note of a scale, and the note leading up to it, were only a semitone apart (the "ti-do" effect). So they sharpened the seventh note of the aeolian mode to create this effect, this is known as the harmonic minor scale (ie sharpening the G# in the A minor scale). However this created another problem, the gap between the 6th and 7th note was too hard/awkward to sing. So they made a rule that you sharpen the 6th and 7th note on the way up the scale, and flattened them again on the way down. This is known as the melodic minor scale, so:

Standard Aeolian mode = A Natural Minor
Sharpenend 7th = A Harmonic Minor
Sharpened 6th and 7th = A Melodic Minor

Hope that sorts out a few questions!

cinneide

I think it's important to remember that the key of a piece of music is a dynamic thing - it's not always possible to say with certainty which key a few bars are in.

Sometimes songs will borrow chords from different keys without necessarily changing key themselves. Sometimes music will be purposely written to be musically ambiguous. Radiohead's "Just" and Blur's "Coffee and TV" spring to mind as two tracks that are a bit all over the place. In cases like these, the idea of a key signature loses most of it's meaning.

That said, in the previous example (Dm Em F G), I'd probably say that the key signature was C major - it's certainly the context in which those chords are most likely to appear.

shanejunkin

Based on Ogy's input (thanks by the way, I now see the point that I missed earlier) that that chord sequence is actually in the key of D Dorian.

There are no sharps or flats used to build those chords and it resolves to D. Those are the characteristics of the D Dorian mode? I think!

Thanks for all your help, that's cleared up a lot for me.