Learning how to play Blues is very important even if you do not like that style of music in particular. A lot of rock and pop is directly built on top of the blues song template. Those that want to learn jazz, or anything else really, need to have the basics down before progressing to more complicated theory. The most prominent of all Blues songs or templates is the 12 BAR Blues. The name describes the length of one verse of the blues which is 12 BARs or measures. If you do not understand what I mean by a BAR you need to go over to the Rhythm and Time section and take a look.
We’ll start by going over the chord progression or formula for the typical 12 Bar Blues. We should learn the song like a formula so we can change keys easily. When someone asks you to jam some blues with them you should respond by asking what key they want to play the song in instead of proclaiming that you can only play blues in one certain key. Of course if you have just started practicing that answer will have to suffice. We will use the Major Scale as a reference point but remember that when we play Blues that all of the chords are Dominant Sevenths or just plainly Sevenths. The Progression/formula looks like this if no key is designated:
For Practical reasons we continue to the first key selected which is Blues in E this means that we use the I-iV-V(1-4-5) chords using the Major Scale in E as reference. The 1st note in E Major is E of course so the first chord is E7. The 4th note in E major is A so the 4th chord will be A7. Finally the 5th note in E major is B this means that the fifth chord is a B7. If you don’t remember the chord shapes go to the open chords section.
Playing blues with the basic chords quickly becomes tedious so we should jump into the shallow end of the pool and start practicing “Riffing”. The first riff pattern I cover is quite simple and is used a great deal. Lets just call this simple variation of a “blues riff” Variation 1. This Riff Pattern fits over two beats or half of a BAR. Which means you play the riff twice over each BAR. The riff in the first BAR below is repeated over the subsequent BARs with the same CHORD e.g. the first four bars are the same.
Variation 2 is a slightly more complicated pattern that fits over single Bar or 4 beats.
Variation 3 is the final Riff variation that I will cover here. This is a longer version that fits over 2 BARs. Be attentive when you play the B7 and A7 in the last row (BAR nr. 9 and 10) because we can only play half of the riff over those chords. This type of blues could be called boogie bass or boogie blues maybe.
These are just IDEAS. Try playing with the patterns e.g. mixing them together to create your own variation or blues riff!
This takes care of the Rhythm guitar. What about the lead? Now like I have mentioned before the lessons here are structured logically which means that if you want to learn how to solo or improvise over the above song ideas you need only go the Pentatonic Scale section and learn the Pentatonic Scale in E minor. If the blues is in E use the E minor Pentatonic(blues scale) over. If the blues is in another key like A for example you should use respective Pentatonic Scale or Am Pentatonic.
Now the interesting thing about BLUES in general is the interaction between the “major”-dominant 7th progression and the Minor Pentatonic Scale this creates the interest or tension that people are drawn to.