Part I: Major/Minor, Suspended, And Seventh Chords
In order to learn from this article you are expected to already be fimiliar with both the major and minor scales.
Using the scale degrees from the major scale we can learn how to formulate chords, as well as identify the names of them. Like a majority of aspects in music we will use the standard major scale as reference. To create the most basic chords we need a series of three notes, hence the name "triads". As you may already know these chords are composed of the first, third and fifth notes of the scale. If a chord is composed with a natural third the chord is major, if the third is flat it a minor. A major chord is simply represented by the letter of the root note and a minor with a lower case 'm' afterwards. So if you see simply a letter representing a chord, it's imply that it is major. Generally speaking, major chords sound happy or cheerful and minor chords sound solemn or sad, but it all depends on the context. Here's two examples of commonly used chords:
[ C E G ] C (major)
1 3 5
[ A C E ] Am
1 b3 5
If you look at the neck of those open chords you can easily identify the notes as fitting in that pattern. An open C chord is [ C E G C E ] and the open A minor chord [ A E A C E ]. See how the notes are arranged in a different pattern? This is referred to as voicings. The only thing you'll really need to know about a chord's voicing at the moment is that the root note is assumed as the lowest pitched note of a chord. If not, the name of the chord should indicate the root name is altered with a slash followed by the note (ie. C/G; the chord requires you to fret the third fret of the low-E string in a basic open C chord, subsisting the C the root note for a G). This can also be note for root notes that are not in the chord otherwise (ie Am/G), as the altered bass note strays from the generally harmony of the rest of the chord. These are called inversions.
Back to the chord analyzation. We came to that conclusion on the preceding chord because the third of an A major scale is a C#. We don't simply apply scale formulas of a minor scale even if it's a minor chord. It is important to always apply the degrees of the scale of the root note NOT the key that the song is in.
So, since those are two are commonly seen let try reversing the chords; and find C minor and A major.
[ C Eb G ]Cm
1 b3 5
[ A C# E ]A(major)
1 3 5
See all we had to is apply the scale degrees. The open A major chord is in a similiar shape to Am, the third is simply raised (one fret higher).
However, I guarantee you don't know how to play a Cm chord (save barre chords). That is because that particular chord is unconventional of the guitar neck (in standard tuning at least); mainly because there are two open E-strings and there is an Eb in the chord. The reason a guitar is constructed with the strings tuned to the notes they are, and the intervals between each string is because it's conventional to play chords in simple keys, with limited sharp/flat notes.
If a singer prefers singing in such a key, it is useful to alter the pitch so (ie. System of a Down tune to Drop C to play in C minor, also many musicians use a capo to transpose the key while still being able to play conventional open chords and such).
There are two others triad chords you probably won't use very often, considering how dissonant they sound. They are they augmented and diminished chords. The word augment means to extend in size and diminish to reduce. And that's precisely what happens to the scale degrees.
[ E G# B# ]Eaug
1 3 5#
[ E G Bb ] Edim
1 b3 b5
So to compose these two types of chords we, in the case of augmented sharpen the fifth, and in the case of diminished flat the third and fifth. Both are undoubtedly horrid sounding chords, which is why they aren't commonly used. An augmented chord tends to only be used as the fifth chord before the resolution to the root, or as a sixth followed by the fifth (a pre-cadence) while a diminish chord can resolve back to a regular 1-5 (not-flat 5th) diad, making the b5 an accidental in the scale. It can also be used diatonically as the VII chord in the major scale or the II chord in the minor scale. These chords may be written as they are above, with three letter abbreviations, or a plus sign may be used to signify an augmented chord and a degree sign for a diminished. Conventionally, "real" diminished chords contain extensions. A diminished chord also contains a bb7 (yes double flat, enharmonically equivalent to a 6th), so if you see a diminished chord written in a piece it indicates that it contains that note. Otherwise it would indicate that it's a triad. More commonly used though, particularly in jazz is the half-diminished or minor seventh flat fifth (m7b5) chord. It is an altered chord, which I will explain in later in the lesson after you learn about extensions.
Suspended chords are an odd type of chord, because they are essential the only ones without the presence of a third. Without a third the chord cannot be labeled as either major or minor; this means the chord has no specific emotion that a major/minor chord acquires. There are two types of suspended chords; 2nd's and 4th's.
[ A B E ]Asus2
1 2 5
[ A D E ]Asus4
1 4 5
Suspended chords are well, suspended, so they are easy to use in progressions and to resolve to other chords, particularly the root. The extended usage of suspended chords is for the suspended note to move a semitone towards the third. So in the provided examples the B in the Asus2 would want to move to a C, creating an Am chord (I'm sure you've seen this used in many songs), and the D in the Asus4 would want to move down to a C#, creating a A major chord. However, suspended chords are now used in many other contexts. For example, you can use the sus4 chord as a IV chord, because it flows easily back to the root considering it contains two of the same notes. (ie. Asus4 [A D E] to D [D F# A ] ). There are many opportunities to use suspended chords because five of the seven notes in a scale have the option of using the natural second or fourth.
Usually a suspended chords only uses the suspended note (2nd or 4th) once, while the the root and fifth are doubled if necessary, just like in the examples given; & or (AEABE) (AEADE). Suspended chords are most commonly constructed in the shape similar to major and minor barre chords. The following are examples of Csus2 & Csus4 chords & . You can move these shapes around the guitar neck. You can think of it this way; the suspended second is one note lower that a flat (minor) third and a suspended fourth is one note higher than a (major) third.
Next chord in our study is seventh chords. No doubt you know how to play a few and have seen many in jazz or blues. They are the most commonly used chords besides the basic major and minor triads. The Dominant 7th, which is what you assume a musician to be referring to when they say "7th", is composed of the root, third, fifth, and flat seventh. Let's try a very common G7 chord.
Now trying playing a G7 <320001> and afterwards play a C major chord. The reason this transition sounds so good is because the G7 is the dominant fifth chord of the key of C major. That means this chord will (G7) will build the most tension before resolving to the root. It's like lifting a load of weight off your back and feeling the relief. This transition is called a perfect cadence.
Do you notice anything in particular in the construction of dominant 7th chord? Well, the interval between the third note and the flat seventh is a tritone (diminished fifth, or augmented fourth). This is where a majority of the dissonance originates. When you shift back to the tonic (the I chord; the chord with the root note of the key - C major in the example), the tension resolves, making the I chord sounds oh so much better.
There is also, like all other chords a minor version. The only difference is that the third is flat, just as it was in the triad. I will provide you with the previous example now as a minor chord, and a commonly used minor 7th chord; Em7.
Minor seventh chords work in the same tension building progression that dominant sevenths do, except minor 7th process in most likely used in a minor key, where the minor 7th chord is the fifth, resolving the tonic which is also a minor chord. So in this example a Gm7 would resolve to a Cm chord instead of a C major, and the Em7 <022030> would resolve to an A minor.
However, many composers choose to borrow a dominant 7 chord from the major scale to use as the V chord in a minor key. The dominant 7 chord contains a sharp seven of the minor scale when used as the V chord, which has a strong pull towards the tonic. This is the origin of the harmonic minor scale. The seventh is raised (or borrowed from the major scale), so the dominant chord can be major. For example In E minor, a B7 used as a dominant chord contains a D# as the third, where as the natural minor scale would contain a D. However, it's not written in stone that you have to use the harmonic minor scale if you want to used a major 7 chord. You could use the accidental as a passing tone, (ie. D - B7 - Em), or in another context.
Another common seventh chord is the major seventh. Now seventh chords can get confusing because there is the dominant seventh which technically has the major triad in it, then there are these chords major 7th which also have the same major triad but has a natural, or major 7th. Just remember that the word major in this case refers to the seventh. All chords are implied to be major already, unless specified otherwise. The scale degrees to a maj7 chord are simply first, third, fifth, seventh - no accidentals.
[ G Bb D F ]Gm7
1 b3 5 b7
[ E G B D ]Em7
1 b3 5 b7
Notice the interval from the 7th to the root is only a semitone. This not only provides disonance, but means unlike dominant sevenths (which have a flat 7th) they can be used as the root note chord (in the major scale, of course) One way to resolve tension is to move the 7th up to the root (which would the octave; 8th) - try moving to . Maj7 chords also sound somewhat good progressing to the sixth, or reversely functioning as a third - try moving Cmaj7 to A minor. Major seventh chords can also be used as the fourth scale degree. This usage of the chord resolves fairly well to the tonic. Try Fmaj7 to C. Not bad, but it's not a perfect cadence like the dominant 7th chord, because there isn't that tritone interval in the chord begging to be resolved. The transition between the two chords is smooth because the F already contains a C as its fifth, and with the maj7 an E, the third in the C chord, so they contain two of the same notes.
There is one more type of 7th chords and it's the minor, major 7th. A bit of a tongue twister but it's the minor version of the major 7th chord. They are written like so; AmM7, the little 'm' representing the minor third and the big one referring to the major 7th. The scale degrees are the root, flat third, fifth, and seventh. Here's some examples:
They are in my opinion the least pleasing sounding of the 7th chords and I can't recall ever using one in a song, but hey, save the best for last I guess. The chords are exactly applicable as they don't fit in the traditionally minor and scales. Notice there's a flat third but major seventh. There would have to be a major third for it to be in a major scale, or a flat fifth for it to be in minor. However, this chord will fit in the Harmonic Minor scale, as the seventh is sharpened semitone. This chord is used most often in jazz and soundtrack music. It was used in the James Bond theme and in the movie Psycho, for its dissonance. However, it can be used in other contexts like in Pink Floyd's Us and Them. I wouldn't worry too much about this chord or trying to use it, just like the diminished and augmented.
For reference here is the chord's we just went over and their scale degrees.
[ A C E G# ] AmM7
1 b3 5 7
[ D F A C# ] DmM7
1 b3 5 7
Major [ 1 3 5 ]
Minor [ 1 b3 5 ]
dim (triad)[ 1 b3 b5 ]
aug [ 1 3 #5 ]
sus2 [ 1 2 5 ]
sus4 [ 1 4 5 ]
7 [ 1 3 5 b7 ]
m7 [ 1 b3 5 b7 ]
maj7 [ 1 3 5 7 ]
mM7 [ 1 b3 5 7 ]
Part II: Dominant Chords
Alright, we left off last lesson with learning the four types of seventh chords. From those chords we can actually expand and create three different types of extended chords by adding even more scale degrees.
From an existing 7th chord, we simply add a ninth scale degree as the name suggest. Since there are seven notes in a scale, the eighth degree is a repetition of the root an octave higher, so logically the ninth is an equivalent note as the second. It is vital that the second is raised an octave, because it gives the chord it's flavour. Try playing a C on the A-string with the open D-string (it's second) and compare it to playing that same C with the D raised an octave (2nd string, 3rd fret). It's a completely different sound.
The reason a root doesn't coincide well with the second is due to the critical band. In the inner ear, the cochlea; sound stimulates a wide range of receptor cells along the basilar membrane. The membrane is most deformed and the receptors most activated at certain levels of frequencies. Two frequencies form a dissonant (not pleasing to the ear; wanting to resolve to another chord) interval when their critical bands overlap. By falling close together along the cochlea, two sounds upset eachother's perception. Hence, why tones a half-step or full-step (second) don't compliment eachother.
If you've taken physics you've most likely study the process of beats before. Beats are the frequency difference between two simultaneous sounds. If an in tune A at 440 Hz is heard with a frequency of 445 Hz a beat can heard five times a second. It literally makes a swishing sound. When musicians tune their instruments they can use their presence of beats to flatten or sharpen the sound until the beat dissipates and the notes become equivalent.
The human ear can typically hear beats up to 20 per second. The difference between the notes we used in the example were 130.8 Hz for the C and 146.8 Hz for the D pitch. As you can see the beat level is 16, less then 20, so our ears pick up the beat and experience an unpleasant sensation. This also why when you play that C note along with the D, it has the tendency to want to resolve into a D itself. Our ears literally perceive the C is an out of tune; flat D. A composer can use this to his advantage; by resolving the C to the D (try hitting both the fretted C and the open D, then slide up the C to a fretted D two fret higher, while holding the open D). However we would typically not want this if C was the root note of the chord, since we could mistake it for being the seventh of the D. When the D note is raised an octave, the ear no longer experiences the beat sensation and the critical bands no longer overlap, which diminishes the dissonance.
Science aside, the ninth chord gives off a bright tone and are used frequently in types of jazz and funk. They are similar to the suspended chords we saw in the last lesson (and if you noticed suspended 2nd are almost always placed as 9ths), except they have the influence of the third, providing emotion, as well as the 7th adding tension. These chords are considered more advanced simply because they're harder to stumble along considering there's five necessary notes and only 6 strings on a guitar. A common shape for a ninth chord is starting with the root on the A-string with the middle finger, accompanied by the major third with the index finger (one string higher, one note closer to the neck), and a barre with either the ring on pinky on the same fret as the root. To make the chord minor, simply flatten the third.
In minor 9th chords the third and ninth degrees are only semitone apart, which provides dissonance. You can either spread these degrees as in the example or you can cram them close together. Try this chord voicing out: Dm9 Sometimes you can use dissonance to your advantage, it all depends on what chord you are moving to afterwards, just never attempt to end on a dissonant chord, or it will be a musical disaster.
11th and 13th Chords
We can extend 9th chords even further to create 11th and 13th chords. Traditionally, 11th chords which also contain the 9th and the 13th will contain the 9th and 11th, but since a guitar has only six strings and those chords contain six and seven note respectively, omissions are necessary. It is vital however, not to omit the 3rd or 7th, as they are essential to maintain the dominant quality.
Like so; C9
[ C E G Bb D ]C9
1 3 5 b7 9
[ C Eb G Bb D ] Cm9
1 b3 5 b7 9
Notice how a thirteenth chords contains seven notes, which is the amount of a standard scale? Logically, we can determine what scale we're playing in, just by analyzing those notes. If we look at the A13 scale degrees we can come up with a formula by transposing the 9, 11, and 13 down an octave. It is as follows; [ 1, 2, 3, 4, 5, 6, b7 ].
Now this pattern is similar, but is not coherent with the major scale. This is because of the flat seventh; therefore we can conclude that this chord is not used as the root. If we recall modes we can recognize this formula as Mixolydian. And if we count up this mode occurs on the fifth scale degree, so this is where the chord will be played.
If we use the same method with the minor thirteenth chord, we find the formula; [ 1, 2, b3, 4, 5, 6, b7 ] This is the Dorian mode. It is resemblant of the minor scale, except the natural sixth. This mode occurs on the second degree of the major scale. However, a more efficient manner of usage is to approach it from a minor scale. Which, if we calculate, once again occurs on the fifth degree. Therefore we can conclude that an A13 chord we resolve to a D major chord, while a Dm13 will resolve to a G minor chord. And as always the chord which a piece resolves to, is that key in which you are playing.
Now you may have noticed the pattern here. These chords with a flat seventh are always played on the fifth scale degree. This is the only place in which you can play them while still remaining in key, which makes them dominant chords. They are the chords that build up the most dissonance before resolving, so they are the most commonly used cadences.
Here are all dominant chords and their formulas. Remember, that typically dominant major chords resolve to major, and dominant minor resolve to minor chords, in a minor key. The major seventh chords we learnt in the last lesson do not qualify as dominant chords, because the seventh degree is natural. However, the dominant seventh (obviously) and minor seventh are.
[ C E G Bb D F ] C11
1 3 5 b7 9 11
[ E G B D F# A ] Em11
1 b3 5 7 9 11
[ A C# E G B D F# ]A13
1 3 5 b7 9 11 13
[ D F A C E G B ]Dm13
1 b3 5 b7 9 11 13
(dom)7[ 1, 3, 5, b7 ]
m7[ 1, b3, 5, b7 ]
9[ 1, 3, 5, b7, 9 ]
m9[ 1, b3, 5, b7, 9 ]
11[ 1, 3, 5, b7, 9, 11 ]
m11[ 1, b3, 5, b7, 9, 11 ]
13[ 1, 3, 5, b7, 9, 11, 13 ]
m13[ 1, b3, 5, b7, 9, 11, 13 ]
Part III: Add, Altered And Sixth Chords
I'll try to go over these last three chords quick so we can sum this lesson up. Sixth chords, as suggested by the name contain the sixth, as well as the basic triad, but don't always require the fifth. Sixth chords are basically inversions of the VI chord. The chord contains the exact same notes as the VIm7, without the fifth, it contains the same notes as the VI triad. Sixth chords can be used effectively as the VII chord in a minor scale, because it is an inversion of the dominant chord and has a strong pull towards the tonic. It can also be used well as the IV chord in major, as well as the I or V. There are also minor 6th chords (with a flat third). They are very effective for chord substitutions.
Add and altered chords will explain the rest of the chords that will encounter. These chords include the other that don't fall under any traditionally recognized chord patterns. Add chords take the basic triads and add extensions such as the 9th and 11th (i.e. Cadd9 , Dadd11 , Emadd9 <024000>, Amadd9 ). These chords are used a lot in progressive rock. Both the major add11 and the minor 9 contain intervals that are a semitone apart. That gives the chord its signature sound. Now altered chords are any chord follow by a certain scale degree identified as being flattened or sharpened a semitone. Examples include the "Hendrix" chord 7add#9 <076780> and the m7b5 or "half-diminished as I alluded to earlier. Because altered chord can include any alteration of any note, each one provides a different sound. However, they are usually dissonant. So when you encounter an altered chord, simply do what the name tells you to.
A chord can be used at a scale degree as long as the notes in the chord fit in the formula of the scale degree's mode. I'll list examples of chords that can be used in each scale degree. The earlier the chord listed the more relevant it is. Using these chords you will never go outside of the seven note scale.
If you're playing in a minor key, then just start the scale degrees from the same pattern - starting this time on the vi.
I.maj7, 6, sus2, sus4, add9, add11, maj9, maj11, maj13
ii.m7, m9, m11, m13, m6, 7sus4, 7sus2, sus4, sus2, madd11, madd9
iii.m7, 7sus4b9, 7sus4, mb6, sus4, addb9, add11
IV.maj7, maj7add#11, maj9add#11, 6, sus2, add9
V.7, 9, 11, 13, 6, add11, 7sus2, 7sus4, sus2, sus4, add9
vi.m7, m9, m11, m13, madd9, madd11, sus2, sus4, 7sus2, 7sus4
i.m7, m9, m11, m13, madd9, madd11, sus2, sus4, 7sus2, 7sus4
III.maj7, 6, sus2, sus4, add9, add11, maj9, maj11, maj13
iv.m7, m9, m11, m13, m6, 7sus4, 7sus2, sus4, sus2, madd11, madd9
v.m7, 7sus4b9, 7sus4, mb6, sus4, addb9, add11
VI.maj7, maj7add#11, maj9add#11, 6, sus2, add9
VII.7, 9, 11, 13, 6, add11, 7sus2, 7sus4, sus2, sus4, add9