Learning how to play and improvise great blues riffs and licks is not as easy as it might seem to a novice but the one good thing is that focused learning and practicing with a great blues backing track will help a lot in understanding blues chords and progression.
Using blues backing tracks is an important aspect of playing blues lead guitar. Blues is considered to be one of the origins of jazz music and you will find some influence of blues even in contemporary jazz. Most of the blues music and the ones used in common blues backing tracks are pentatonic scales and the mixolydian scales. These scales can be used in rock too and hence the ones used for blues are enhanced with the blues notes. If you understand the basic of the blue notes then you will be able to improvise over blues backing tracks with ease. Basically, blue notes use a drop in the pitch of the 3rd, 5th and 7th of the major scale. If you hear a professional talk about a blues scale then what they really mean is the pentatonic minor scale with a blue note like b5.
There are many people who jam to blues backing tracks in the C key and the chords used could be C, C7, G7, and F7. If th tracks are meant for a solo then the Am pentatonic scale will be rather useful and perfect to a certain degree. Some of the other options of blues guitar backing tracks include C-minor pentatonic comprising of the c-blues scale and c-major and Bb major scales in Dorian mode.
Blues Chords and Progression
Here are some characteristics of the blues chords and progression, which will unquestionably help you to play great blues guitar effectively:
Most of the blues chord progressions are in a 12 bar form. Apart from this, you will also find 14, 16, 24 or even higher number of bar forms for blues. The tonic chord in blues progression is basically the dominant 7th chord. The blues music has been predominantly defined not only as music that focuses on chord changes as well as scales but also on feeling. There are 3 basic chords in blues and they are all dominant 7th chords.
A few of the blues backing tracks improvisation techniques include:
Using hammer-on or even a slide right from b3 to natural 3 Mixing the Mixolydian scale with the dominant blues scale
Mixing scales is probably the best way of enhancing blues guitar playing techniques.
In the first part, you need to use the C Mixolydian scale with a natural 3. In the second half of the 2nd bar, you need to use the C-minor pentatonic scale using a flat 3. If you really want to pursue blues guitar techniques then the best place to learn is by listening to recording of blues guitarists or legends like Buddy Guy, Eric Clapton and Stevie Ray Vaughan. You can also listen to some of the compositions of famous jazz guitarists like Kenny Burrell and George Benson.