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What Makes The Blues So Blue? | Lockdown Learning | Conversation Kickstarter

Updated: Aug 5, 2021

This week, we dig into the origins of the Blues and the inner workings of the well-known 'Twelve-Bar Blues’ structure.

Blues Music

For GCSE and A-Level musicians, knowing your way around the 12-bar blues and having some jazz theory under your belt can be invaluable when analysing popular music from the 20th and 21st century. But where did the Blues come from, and why is it so blue? In today’s ‘Conversation Kickstarter’, I’ll be examining the history of this well-known song form before diving into the nitty-gritty of how the 12-bar blues functions.

Origins of the Blues

When someone says they might be ‘feeling blue’, it’s often a connotation that they’re having a pretty terrible day. Maybe they didn’t practise for an important exam, or maybe they forgot to make a revision timetable. We all have these sorts of days! The association of the colour blue with feeling sad goes back hundreds of years and plays an important role in the underlying sentiment of many Blues tunes.

The precise origins of the Blues are relatively unknown. While the first real Blues ‘tune’ might have been written by Antonio Maggio – “I Got The Blues” – in 1908, many historians will direct you towards the mid-19th century as a starting point of this emotionally-charged genre. Here, African American cotton pickers in the Deep South – in particular near New Orleans and the Mississippi Delta - would sing to each other in the plantations.

While this was after the abolition of slavery in America, many of these workers would be former slaves in exploitative ‘sharecropping’ arrangements with the pre-dominantly white landowners. This practice, where workers rent land and make payment by giving a proportion of their output to the landowner, would leave many poor farmers with little financial security and greater debts (from the additional use of agricultural supplies) than they would through standard renting. The shift towards sharecropping in the 1870s made cotton-picking the major economic activity in the Deep South – so much so it would be referred to as the ‘Cotton States' – just as the price of cotton began to fall, sending many workers into deep debt as they struggled to meet increasing crop quotas.

As you can see, you would probably be feeling blue if you were a farmer during this time! At the plantations, field hollers would create ‘call and response’ style songs in the fields, often featuring spiritual themes. This call and response structure has its roots in traditional African music and was introduced to America by slaves brought across by the trans-Atlantic ‘triangular’ trade. This format paved the way towards the twelve-bar ‘AAB’ structure. Likewise, the use of ‘blue notes’ (flattened third, fifth and seventh degree of the major scale - so in C the blues notes would be Eb, Gb and Bb) is inspired by West African ‘just temperament’ tuning (i.e. using the harmonic series), a breakaway from traditional European ‘equal temperament’ tuning, giving the Blues its unique, melancholic mood.

From these early origins, the Blues developed into the style we all know and love today. In particular, it would grow to encompass far more emotional themes than just oppression and resentment, embracing more uplifting stories of overcoming struggles or just relaxing and having a good time. That said, it is critical to remember where this music came from; the cotton fields and the ‘juke joints’ populated by African Americans in the Deep South, singing about their economic and social hardships.

Playing The Blues

So we’ve learnt a little about the history of the Blues – how does it all work? Let’s take a look at one of the most common Blues forms, the ‘twelve-bar’ Blues. I’m going to start with what you need to know for GCSE music and then take a look at how A-Level students can step things up a gear and explore some interesting Jazz harmony.

From the offset, the ‘twelve bar’ name is a dead giveaway; the structure is twelve bars long! At it’s most fundamental, a standard Blues will consist of I chords (the home key - let’s say C major), IV chords (we might call this the ‘subdominant’ – in C this is F major) and V chords (dominant chords – in C this is G major). The basic format then looks a little like this:

Simple Blues Structure

Pretty simple right? Of course, we’re not quite done yet. It’s time to talk about those chord extensions. To help add a healthy dose of harmonic tension, Blues music frequently uses ‘dominant 7th’ chords. This is a fancy way of saying that we’ll add the flattened seventh degree to each triad. Running on the basis you know what a major triad looks like, let’s add the b7 to each chord in our Blues. So in C, the seventh note of C major is B so our dominant 7th is C-E-G-Bb. In F, it’s going to be F-A-C-Eb and in G it’ll be G-B-D-F. On the chord chart, we've denoted this by adding a little ‘7’ beside each chord.

Now things are starting to come together! For GCSE musicians, this will be as much as you’re expected to know harmonically. To take this a step further, I would recommend looking into building a ‘boogie-woogie’ bass line and using the Blues scale to start writing a melody, or perhaps even trying your hand at some improvised soloing.

Are the A-Level students (or ambitious GCSE musicians) still with me? Before we talk chords, I’m going to politely ask you to refer back to my all-purpose introductory guide to Jazz harmony I wrote last year. If you’re happy with the material there, we can crack on!

First things first, we can think about making this form a bit more… exciting. Jazz is very much from the same family as the Blues, so it’s no surprise that ‘Be-Bop’ musicians started tinkering with the well-known twelve-bar form. A common Jazz blues (I'm thinking of something like Sonny Rollins' 'Tenor Madness') might look a little like this:

A Be-Bop Blues

Now, there’s a fair few changes here, so let's run through them one by one. The IV chord in bar 2 is pretty innocuous, it's there to add some harmonic colour more than anything. What about bar 4? Recalling what we know about Jazz harmony, hopefully you'll recognise that this is a 'ii-V' (Gm7-C7) into our IV chord in bar 5 (F7). This helps add some nice voice-leading into the middle section. At bar 6, we have an F# diminished 7th chord (or we can think of this as iv# diminished chord), denoted by the small 'o' and the '7'. Put simply, this is a stack of minor 3rd intervals, so F#dim7 would be F#-A-C-Eb. In this blog about Christmas music, I spoke a little about how diminished chords have an unusual property, they can be utilised as dominant chords to help us cadence to a new chord. They can also be nice passing chords, and that is precisely how it is used in this instance. Between F#-A-C-Eb and C-E-G-Bb, all the notes (asides from C) move chromatically up half a step, which adds plenty of tension and sounds great to our ears. Try playing it for yourself on a piano!

Over in bar 8, we have, surprise surprise, another ii-V heading into the chord in bar 9. This time, we're moving towards the Dm7 in bar 9, so we're using chord iii7 (Em7) and chord VI7 (A7) to help us voice lead towards it. You'll notice that the A7 has an added extension - the b9. This is essentially the flattened '9th' scale degree (so in A's case, the natural 9 is B and the b9 is Bb), which adds a nice 'crunch' to the dominant chord. So much of Jazz harmony is about creating tension and releasing it and these chromatic extensions really help in that regard. Of course, like many things in life, crunchy chord extensions must be used with moderation!

Wrapping things up, we have another ii-V between bars 9-10 (Dm7-G7) heading towards our home chord, C7, in bar 11. Phew! All that's left in bars 11-12 is what Jazz musicians call the 'turnaround'. Thankfully, it's one you should be familiar with, the classic I-VI-ii-V. This helps add a bit of harmonic structure to the Blues and allows the listener / band hear that the form is about to repeat.

Closing Thoughts

If you just tuned out for the Jazz theory geekery, welcome back! I hope this has been an insightful introduction into the world of Blues music. While this has certainly stretched what you need to know for the curriculum, it's so important to have a good knowledge of where the music you learn about in class comes from - music students can study history too!

Especially in Jazz and Blues music, it is vital to understand the historical struggles of African Americans, who's overwhelming contribution to these beloved styles is immeasurable. So, you know the drill. Strike up a conversation over dinner or on a (socially-distanced) walk, who do you know who likes listening to Blues and Jazz? Do they know what makes the Blues so blue?

Blog Post Crafted by Oscar

Oscar studies Philosophy, Politics and Economics (PPE) at the University of Warwick.

When he's not studying PPE or tutoring GCSE Maths and Science, Oscar plays the saxophone and is the Musical Director for the University of Warwick Big Band.

In 2017, he set up his own jazz function band, Mirage Quartet, and has been a keen collaborator and ambassador for Bromley Youth Music Trust.


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