Music Theory/Blues
From Wikibooks, the open-content textbooks collection
Blues genre of music originally came from the USA in the 19th century and was a form of music played by black slaves. It was full of soul and emotion and some may even be found as depressing. The original blues music often contained sad lyrics that dealt with everyday issues of life that the slaves found hard to cope with.
Slowly, as blues became more popular and spread into the urban areas, it gradually became more 'happy'. By 1920, three major formats of blues were common: The 8 bar blues, the 12 bar blues and the 16 bar blues. Blues also developed various styles, or subgenres, such as Mississippi Delta blues and Chicago electric blues.
Contents |
[edit] Blues scale
To understand Blues chords, first you need to understand the scale that is associated with the 12 bar blues, which, unsurprisingly, is called the blues scale. It follows the pattern:
I, IIIb, IV, Vb, V, VIIb, I
in relation to the I major scale. The IIIb, Vb, and VIIb are considered to be the 'blue' notes, and characterise the style.
In terms of intervals, or distances between notes (in half steps), the pattern is:
3, 2, 1, 1, 3, 2
In other words, three half steps from the tonic (I) to the second note of the blues scale (IIIb), two from the second note to the third (IV), one from the third to the fourth (Vb), and so on.
In C:
- C, Eb, F, Gb, G, Bb, C
In D:
- D, F, G, Ab, A, C, D
In G:
- G, Bb, C, Db, D, F, G
The reason I talked about these three scales as examples is to illustrate the next point of blues: Blues are made up of I, IV, and V chord. In the case of Blues in G, that would be in G major, C major, and D major. However, we do not use proper major scales, but use the blues major scale. As seen from the above example, 2/3 of the notes in IV chord and V chord of G blues scale are in the C and D blues scale. Thus, the artist can just focus on the notes in the key of their song.
- Note: 'Blues scale' is a somewhat disputed term, also used by many to refer to the minor pentatonic scale: I, IIIb, IV, V, VIIb, I, or intervals of 3, 2, 2, 3, 2 half steps. The blues scale outlined above is a minor pentatonic scale with a note (Vb) added in between the IV and the V. Blues music generally uses the minor pentatonic scale, and often includes the added note, making it a blues scale. The term 'blue note' is used in various ways as well. In addition to the meaning given above, it can refer to the added note that turns a minor pentatonic into a blues scale, or to a note that is flattened by less than a semitone.
[edit] 12 bar blues
12 Bar blues is still the most popular blues pattern, and is adopted by many contemporary musicians. Numerous variants exist, but this is the general outline:
I | I | I | I IV | IV | I | I V | IV | I | I
In the key of C, these will be the chord progression:
C | C | C | C F | F | C | C G | F | C | C
Some common changes to this pattern include making some or all of the chords into seventh chords (I7, IV7, V7), which can give an even more bluesy feel to the progression, or substituting a chord in one of the bars for another chord. For example, the final I is often changed to a V or V7 (in the key of C, a G or G7) instead, which is known as a "turnaround", and generally sets up for another verse (since the V or V7 chord naturally leads to the I).
[edit] Verse forms
Each of the blues progression equates to one verse of the song, and during soloing, verse form should also be observed. If a verse is split into three blocks of four measure, numerous verse form can exist within a coherent framework. While there can be numerous kind of verse form, the following are the most common:
- A-A-A. A block is repeated three times. Containing no B section but a repetition over and over; often used to tell a story with a song. It is also common to have a turnaround near the end of A.
- A-A-B. The third block is new in the verse. This is good for vocal lines.
For the two above, you can always have a few variations, making them sound similar but different.(eg: A-A'-A") For example, repeat the "A" block a little bit, or change the end a little bit.
- A-B,C-C. The second block uses two measure of B material, then follow by two measure of C materials.
- A-B-C. Formless. May give a prescene of melodyless. Useful for jamming mainly. Sounds easy, but actually very difficult, since if done poorly can bore the audience easily.
[edit] Jazz Blues
One of the most interesting Blues variation is the Jazz Blue Progression:
Variation 1 I7 |IV7 |I7 |v7 I7 IV7 |VII7 |I7 |iii7 VI7 ii7 |V7 |I7 VI7 |ii7 IV7
Variation 2 I7 |IV7 |I7 |v7 I7 IV7 |IV#dim |I7 |iii7 VI7 ii7 |V7 |iii7 VI7 |ii7 V7
For those that knows about jazz theory, you may ask where is the ii-V progression is. Actually, it is here: the v-I progression is actually ii-V prgression relative to the the IV chord.
[edit] Lyrics
The lyrics of blues usually takes the form of a narrative. As its origin goes, most of the time the lyrics dealt with personal woes and hard times, or simply their day to day life. Of course, it can be humorous, too. While it was humorous, it differs from other humourous songs by mainly using joyous melodies, and use a more innuendo-laden lyrics. For example, a song by the Blues Brothers:
- I said Woman, you going to walk a mile for a Camel (this can refer to the cigarette)
- Or are you going to make like Mr. Chesterfield and satisfy? (this here to another cigarette, but a certain body parts)
- She said that all depends on what you're packing
- Regular or king-size (again, refer to either or)
- Then she pulled out my Jim Beam, and to her surprise (refer to either the liquor, or the body part)
- It was every bit as hard as my Canadian Club. (again, refer to either or)
Obviously, this can only be done by knowing well not only of numerous vocabulary and synonym, (for example, hard can mean either hardness or alcohol strength), but also of numerous product that can easily take dual meanings.
Unlike many other genre, Blues is more directed toward the audience on the surface, as if doing a simple speech with melodic, rhythmatic, and poetic features, while the other genre's lyric are more abstracted even when just listening. Many early blues lack rhyming, which is seen as needed in many modern songs.
Also, repeating a vocal line is often helpful, since it reinforces the words into the audiences.
For more details on writing a song, go to Writing Effective Songs.
