Audio Design

Copied from: http://www.ultimate-guitar.com/lessons/for_beginners/how_to_know_which_key_a_song_is_in.html

I remember sitting up nights reading a lot of material trying to learn how to read a song, and find out which key a song is in, so that I might easily know which notes to base a solo on. But I haven’t found any good guides that sums it all up, just some guides that seem to include some of the material. This is for beginners, to get a grasp of the subject.

Let’s take a song called Me and Bobby McGee.

The version I play uses the chords G, C and D. Therefore, this song is in G.

Now, why is the song in G?

Well let me tell you how I knew that, because it had G, C and D in it.

Check out this chart:

Now what can we see here? 

Well for startes, 1, 4 and 5 are ALWAYS Major chords(G, C, F# etc). 2, 3 and 6 are always minors(Dm, Am, C#m etc) and 7s are diminished chords, even though sometimes used as a major in certain songs.

So, we have Me and Bobby McGee, a song which has a G major, C major and D major chords in it. Look down the chart, which songs have G, C and D major in it? Ah, G has those three chords. Therefore Me and Bobby McGee is in G.

Lets take another nice country song while we’re at it: 

Three Wooded Crosses by Randy Travis

The version I know of this song uses these chords: C, Dm, Em, F, G and Am(and also Am7, but yeah). 

So, go up the chart and tell me what key this song is in. Scroll down when you are ready.

Yeah, this song is in C.

Now, next song:

Folsom Prison Blues by Johnny Cash

It uses the chords E, B and A. Which key?

Right, its in E (as most of Johnny Songs where).

Now you should have a clearer understanding of which songs are in which key.

Introduction to Chord Theory: Major Diatonics

Here is a brief lesson introducing the basics of chord theory. This lesson will deal only with triads, larger chords will be addressed later.

For the purpose of elementary chord theory, all chords are constructed by stacking intervals of thirds. In addition to this basic rule, it is also a safe bet that you will (for the most part) encounter 4 types of chords: Major, minor, diminished, and augmented.

When you hear a chord, you hear each note and interval from the bottom up. The bass note is what actually makes the chord identifiable. In root position (inversions will be addressed later as well) you start with a single note, the third above that, and another third above that one, which also happens to be a fifth above tonic.

Starting from the bottom:

Major: Major third + minor third

Minor: Minor third + major third

Diminished: Minor third + minor third

Augmented: Major third + major third

Get it? It is quite simple actually. Take for example, a chord with the tonic of C. A C major chord would consist of a major third above C, which is E, and a minor third above E, which is G. A C major chord would be spelled out as [C-E-G]. On the other hand, a C minor chord is the opposite interval combination, a minor third with a major third on top. This would give you [C-Eb-G] which is C minor. How is that for easy?

So, let’s take this one step further. Every major scale creates the “perfect storm” so to speak that allows for each note to have an appointed chord. These chords will never change unless accidentals from outside the key are introduced. Take for example the key of A major, [A-B-C#-D-E-F#-G#-A]. To find the corresponding chord type for each note simply take that note and add every other note after. Take the first note, A, and add C# and E … This gives you an A major chord. [B-D-F#] is a B minor chord, etc… Lucky for you though, since every major scale is constructed from the same combination of intervals, they share a common combination of diatonic (naturally occurring) chords.

In A major

A   (I)- Major

B   (ii)- Minor

C# (iii)- Minor

D   (IV)- Major

E    (V)- Major

F#  (vi)- Minor

G# (vii*)- Diminished

Remember this and you will always know what chords you have at your disposal when working within a given key: I, IV, and V are always major, ii, iii, and vi are always minor, and vii* is diminished. Learn it, love it, make it your own, because you will always use it.

Disclaimer: This only works in major keys! The same system applies to minor keys, but it turns out differently. I will address this in a separate lesson.

- http://metaltheory.tumblr.com/