Agenda: To identify the chords and building chords of any type.

Intervals:

There are different types of intervals like major, minor, augmented and diminished intervals.

An interval is just two notes that have a certain number of semitones (or half-steps) between them. For example, the number of semitones between C and D is 2 ( C => C#, C# => D). Below is a scale of all the different intervals and an example.

The important step to take out of this table is the minor and major 3rds, as well as the perfect 5th.

A chord is defined as 2 or more notes played simultaneously ( usually at least 3). Most commonly used are major and minor chords(VT Music Dictionary). Let us break down what we know as a major chords and show you how this knowledge of intervals will help you build some of your own chords, as well as identifying the name of the chord.

Breakdown of a major chord: C Major

A C major chord is the most common chord that a guitarist will play. C major consists of 3 notes: C, E, and G. Why are these notes chosen to be a major chords? What is it about them that makes it major? Let’s look at it first two notes in this chord: The C and E.

Let’s look at it first two notes in this chord: The C and E. Between them there have 4 semitones ( C-> Db, Db -> D, D->Eb, Eb->E ). Four semitones are listed as being a major 3rd interval. Now let’s look at the last two E and G. How many semitones between them? ( E->F, F->F#, F#->G) If you guessed 3, you are correct. What interval are 3 semitones? A minor 3rd. Since there are 4 between C and E and 3 between E and G, we can assume that there are 7 semitones between the C and G. Seven semitones is a perfect 5th.

So what is all mean? If we look at it from the 3rd, we notice that the first 3rd is a major, while the 2nd 3rd is a minor. It just so happens that this pattern is repeated for every major chord in western music. So whenever you have 3notes where between the first 2 is major 3rd and between the second two is a minor 3rd is a major chord.

Breakdown of a minor chord: A Minor

An ‘A minor’ chord is made up of 3notes as well: A, C, E. As above if we break down these pattern for minor chords. Between an A and C we have 3 semitones means this is minor 3rd. For the other two notes C and E,it is 4 semitones and is a major 3rd.

So , the first 3rd is minor and the 2nd 3rd is major. This pattern is consistent for every minor in Western music. So, if I asked you to build a C minor chord, all you would have to do is chose the minor 3rd above C, and the major 3rd above that note, or a perfect 5th above C. That would mean a C minor is C, Eb, and G.

2 Minor 3rds and 2 Major 3rd is what?

You may be asking yourself: There is more combination of 3rds than just a major and a minor or a minor and a major. What happens if we have 2 minor 3rds or 2 major 3rds. Well, it has to be something, right? Of course, it is! Think about out C major scale. Let’s take the weirdest chord of this scale, the Bdim. What notes are involved in this chord? B, D and F. We have 3 semitones between B and D and 3 semitones between D and F. Well, we have two minors here… does that mean all diminished chords follow this pattern? Of course, it does! Music theory is not that complicated: its a bunch of patterns.

So, if we were to take it the other way, the only chord left is an Augmented. Let’s build an augmented chord. If I wanted a Caug chord, what notes would I play? First, we need a major 3rd above C. We know this already to be an E. What is a major 3rd above E? Count up 4 semitones. E->F, F->F#, F#->G, G->G#(Check the footnote to see why this is a G# instead of an Ab). So, the Augmented chord has the following 3notes: C, E, and G#.

Conclusion:

This is how you build your basic chords. The most important things to remember here are the 3rd intervals, the perfect 5th interval, and what 3rds makeup Major, Minor, Diminished, and Augmented. When you understand these, I would  suggest sitting down and memorizing which 3rds are major and which are minor. Good luck!.

Footnote:

When we are working with scales, there are certain rules in music theory that we follow when working with a key. In this case, we are talking about 3rds chordal intervals. A thrid will always exist as 2 notes with 3 or 4 semitones between them, but another rule is that the name of the note will always be the 3rd note in the scale from the start. As an example, the 3rd above a C will always be an E. Whether or not that’s an Eb, E or E# is up to the theory. But, you will never see a 3rd labelled as C and D# or C and F. This is the case where you end up getting an E# or a B#, even though these notes are exactly the same as F and C respectively.

Agenda: What is a key? and What is a chord?

Key:

A key is basically a group of certain notes in resemblance.

Example: Look at the above picture above and pick a Key, like ‘C’

Now to find out all the notes in this key, just read from left to right.

So now we have for Key C : C, D, E, F, G, A, B

Similarly for Key Bb : Bb, C, D, Eb, F, G, A. 

If you are playing other than these seven then it is called as “Stepping outside the key” or changing keys.

Above are the 12 keys and their common chords. At first glance, it looks like there are 15 Keys, but the Key Gb has the same notes as F# so they are the same. Also, Key Cb has the same notes as the key of B so they are the same. and Db is same as C#. Therefore, we have 12 Keys.

Gb    =     F#

Cb     =     B

Db     =     C#

so now what is Chord?

A chord is just a group of notes played together in brief. The above chart also explains well about what chord belong to what key?

So I am playing Cmaj, Fmaj, and Gmaj chords -> What key am I in?

From the chart Major Minor Minor Major Major Minor Minorb5(b= flat & # = sharp)

To know which key we are in, Consider Key of C

Key of C

The first note in the Key of C and there is a major on top telling that Cmaj is the chord in Key of C

The second note in the Key of C, there is a D and above minor, the Dm is chord in Key of C.

So, coming back to the example above Cmaj, Fmaj & Gmaj by observing these three are the chords in the Key of C.

Similarly, if Bbmaj, Am, Fmaj -> What key am I in? =  Key of F.

What about F#maj, Bmaj, E#m b5  -> Key of F#

What Scale are we in?

To find the scale we have to keep the last 2 notes in the front and that is the related minor scale of C.

The minor scale in the Key of “C” is the Amin Scale.

The minor scale in the Key of “G” is the Emin Scale.

Can the song have more than one scale?

The only thing to identify the Key is to look for the number of # and flats that are different in the above chart we can find like three sharps then it’s in the key of ‘A’ because this Key has three sharps. If it has 2 sharps it’s in the key of ‘D’.

Song can go into different Keys or switch between Keys when soloing over the chords. If that has to sound better if we use arpeggios.

Suppose, there is a song B, A, G… What scale is that in? and a follow up: What lead would I play?

The notes are Bmaj = B, D#, F#, Amaj = A, C#, E Gmaj=G, B, D so the scales proceeds with the notes in it.

If there is song where the scales are not fitting together we can use arpeggios. The use of 1 3 5 , it will never sound bad if played different chord than the as a new key.

If you are switching Keys that is where the cycle of fourths come into play.