What key is this?

[fsf347]

Alright, so my guitarist wrote a song, but for some reason is unsure of the key (he knows very little about theory).

Anyway, the only clues i have were the chords he gave me:

D major (tonic), E minor, C major, A major


Im 90% sure its modal, but I really cant place my finger on it.

Im pretty sure with those being the only chords given that you could assume it is D Major; but its not, otherwise i wouldnt be posting this question, so hopefully this can still be answered with a lack of information..

[|B|rad]

You're probably right, but in my world, you won't find D major, C major, and A major all in the same key signature.

D major: D F# A
E minor: E G B
C major: C E G
A major: A C# E

Arrange those and here's what you get:
D E F# G A B C C#

So depending on whether the C or the C# is out of place, I think you've got either D major or G major. Probably the first, though you gotta account for that c major chord.


Sorry in advance if this is unhelpful.

[Jim Campbell]

Originally Posted by fsf347

Alright, so my guitarist wrote a song, but for some reason is unsure of the key (he knows very little about theory).

Anyway, the only clues i have were the chords he gave me:

D major (tonic), E minor, C major, A major


Im 90% sure its modal, but I really cant place my finger on it.

Im pretty sure with those being the only chords given that you could assume it is D Major; but its not, otherwise i wouldnt be posting this question, so hopefully this can still be answered with a lack of information..

a lot of rock just refuses to fit into the diatonic zone......for your own convenience call it D,and if anything changes you have a point of reference

[bassman1987]

D major (I), e minor (ii), and A major (V) triads are all diatonic to the key of D major, but a C major triad isn't. It's the C natural that does it, and if my theory is correct the C natural implies a Mixolydian mode (C natural being the flatted 7th scale degree in D major).

[ericw]

Originally Posted by bassman1987

D major (I), e minor (ii), and A major (V) triads are all diatonic to the key of D major, but a C major triad isn't. It's the C natural that does it, and if my theory is correct the C natural implies a Mixolydian mode (C natural being the flatted 7th scale degree in D major).

I believe D Mixolydian would have an Am though, and Lydian a C#m... Your song is doomed.

[MalcolmAmos]

Like Jim said It's D something use that and go on. It's a feel right progression - not uncommon from a songwriter that does not understand theory. If you like it just play chord tones and change as he does. If it sounds good it's good.

In it's defence; the D-A finally gets around to a I-V cadence so a loop will develop. Play chord tones and have fun. That loop will walk you into each verse - as long as the new verse starts with the D chord. You will have a small problem with the last verse - gotta end back with the tonic and not the V to end the song.

Show your friend www.musictheory.net -- Lessons then common chord progressions. That ole I IV V I will write just about anything he can think up. IMO - I IV V I makes a good first draft for any new song.

Another thought - if you are shooting for modal, too many chords. http://www.ibreathemusic.com/forums/...hp/t-3564.html

[Chris K]

Wonder why you wrote D major is the tonic.
I mean, if you know that, it could only be in D major.

You can exclude modes though, since modal songs (I mean: the entire song, not seperate chords) are confined to one mode. And modes only know seven different notes.

But why bother? If the chords are chose by intuition (and not based on functional harmony) the key is hardly important.

[tZer]

Attempting to fit the entire piece into a single key signature may not be the correct approach - as many have already said.

You said the chords being used are D major, E minor, C major, A major. How are they being used? As a progression like:
| D . . . | Em . . . | C . . . | A . . . |

Or as sections like:

Section 1: |: D . . . . | Em . . . | D . . . | Em . . . |
Section 2: | C . . . | % | % | % |
Section 3: | A . . . | % | % | % |

That could put section 1 in the key of D, section 2 in C and section 3 in A...

Or...

[MonetBass]

tZer has it right. What's the progression? That would define any modulations.

But since when does rock follow the rules? Call it the key of D major and say the C chord is borrowed (say from the key of G major since it's the closest to D major key-wise) and be done with it.

I use borrowed chords all the time when writing. The question is: does it sound good? If yes, then go with it.

[azureblue]

They often did this sort of thing with the b7 chord- in your case, the C7. Also the ii and the vi Chord- both made majors. And it still worked. Use your ears..

[dalkowski]

Originally Posted by tZer

Attempting to fit the entire piece into a single key signature may not be the correct approach - as many have already said.

+1. See "Giant Steps."

[swelltrain]

It is D major. The progression looks like:
I ii ?? V

Here the ?? should be the vii dim 7, but that chord sounds crazy unstable, and unless the writer has a really good ear for resolving things, or really good theory, it is seldom used. So your guitarist just substituted a C major in there (bVII), which is pretty normal. Just cause there is a substitution chord in there doesn't mean the key has changed-- esp when the problematic vii dim 7 is being substituted out.

Last night my guitarist showed me a song she wrote. The progression used a seventh also, but she chose to substitute with the major chord (instead of Ddim7b5 she just played D). Completely normal. And she also has no clue about theory.

One thing to keep in mind about key/tonic. It is not a recipe that restricts you to certain ingredient notes. It is just a description of where the listener feels like the song want to resolve. And the V to the I in your pattern is the least subtle way of telling the listener WE JUST RESOLVED TO THE TONIC!

[JimmyM]

some of you have a very bad habit of looking to fit all music into a little box. keys allow for having notes out of the key sig by using accidentals. one single mode may not always work across an entire chord progression. the sooner you guys stop looking for boxes and just roll with what you're given, the better off you'll be.

[mambo4]

Yeah, It's D major with bVII7 chord. really common.

such common exceptions are another advantage of NOT thinking modally
...chord tones and passing tones FTW.

[warnergt]

Originally Posted by mambo4

Yeah, It's D major with bVII7 chord. really common.

Got any examples?

[TheBasicBassist]

You could also be able to think of the C maj - A maj progression as a decoration of V, as I'm sure someone has said. Here check this out:

C maj - C E G
A maj - A C# E

So the chord we have here (using A as the root) is, by the way a polychord:
A7#9 (since you guys'll probably be displaced an octave) - A C# E G (C or B#)

OR

The Cmaj can simply be explained away as being an example of modal borrowing from Dm - very common as Mambo said. Take your pick and run with it.

- John

[TheBasicBassist]

Originally Posted by warnergt

Got any examples?

Beethoven, Mozart, Chopin, Gershwin, Arlen, ect.. ect..