In this post, I hope not to bore anyone
But I'd like to examine just why the blues is so popular, particularly amongst the British, who are pretty far away from the roots of the blues
Firstly, the guitar is THE instrument of the blues. It is hard to say which was designed for which: was the blues created for the guitar, or vice versa? In either case, it was a marriage made in heaven.
The guitar is a relatively modern instrument and it took quite a while to sort out the "courses" (number of strings and what notes they are tuned to). That number is, usually, 6 (12 string guitars merely "double up" some notes and repeat others 8 notes higher, so, in effect, a 12 string is played just like a 6 string, as Olly's great clip of Hendrix playing a 12 string accoustic shows).
The strings, from top (thickest) to bottom (thinnest) are: E, A, D, G, B, E
The steel bars which cross the guitar's neck are called "frets". By placing a finger behind the fret over the string, a guitarist plays a note. The magic happens when you realise that there are usually several places on a guitar's neck where a certain note can be found. For instance, the note "A" is the name of the second string down, but logically, starting from the string above (E), the frets work like this:
E = no fret
F= 1st fret
F# = 2nd fret
G= 3rd fret
G# 4th fret
A= 5th fret
Do the same trick on the A string, and you'll arrive at D, which is of course the name of the string below! (things get a little confused at the G string, but don't worry). So, we can get all but the highest notes by going no further than the 5th fret! It's logical.
In effect, this means that many chords (a chord is usually 3 or more notes played together) and most scales have the same visual pattern. In other words, a G Major scale looks the same as a G# Major scale, it is merely moved up (towards the guitarist) one fret. An A Major scale would be moved up yet another fret.
This sounds obvious and logical- and it is! A pianist is playing a much, much older instrument and so scales can be a nightmare for pianists to remember.
Central to blues music is what is known as the Pentatonic minor scale. "Pentatonic" merely means 5 notes which go together well. When one can reduce a scale to 5 notes, this makes things much easier. Most electric blues players hardly deviate from the pentatonic minor scales, which is the same pattern all over the neck.
There also exists the "Blues Scale" which is just like the Pentatonic Minor for most guitarists, but with extra notes added. These extra notes (known as "Blue Notes") are rather odd: they are rather out of place but add an air of.....sadness to the scale. You'll hear them everywhere in blues.
So: we have a rhythmic form of music, often based on or around just 3 chords and often, the guitarist plays his lead part in just one scale, usually (but not always) in the most dominant (common) chord of the song. For instance, if a song mostly uses E chords, then the guitarist will often play in the scale of E.
In other words, Blues is easy
to get started with. It is almost always in 4/4 time (put simply, the beat is every 4 "claps"), which most musicians learn first. Most popular music is in 4/4 time.
Unlike Jazz, there are not thousands of chords to learn. (A guitarist's joke: what's the difference between a rock guitarist and a jazz guitarist? The former plays 3 chords in front of thousands of people, the latter plays thousands of chords in front of 3 people...)
It is endlessly inventive, despite having very simple theory and roots. It's FUN. The blues can make you laugh, cry, get angry, calm you down....
Playing it is like that, too. And no other instrument compares with the guitar for sheer expression and versatility.
And the English in particular have always had an affinity with guitar like instruments. And, of course, there have been lots of Scottish and Irish guitarists, as Mr Gallagher above shows.
But the main thing was: 3 or 4 unskilled musicians could plug away at 3 chords (E,A,B or E,A,D were always favourite) and get the feel and progress in a way that lessons and more formal music just couldn't do.
And the most marvellous thing of all about playing the blues? The awful, wonderful knowledge that no matter how hard you try, there's so much more to be done with it. And that sometimes, just hearing a man sing and clapping his hands or playing the harmonica is more the blues than anything.
It's humbling, uplifting, encouraging and amazing all at once.
Playing the blues, no matter how badly, just makes this 10 times more obvious. Go out and buy a guitar! Do it NOW !