I get a lot of emails asking me about the difference between jazz and blues. Here are some ways to gain clarity about this important topic.
The first thing to keep in mind is that "jazz" and "blues" are just labels. It's all music. So on the one hand, it's not always important to label everything you hear and play. But at the same time, yes, identifying genres can help us understand more about the music we play and where it came from and has developed over the years.
So here's a general way to think about jazz and blues in this context. (Remember that jazz and blues are broad terms and that different people have different ways of looking at them.)
"Blues" started out in the 1800s as a sound, based on a feeling. It generally used the I, IV, and V chords and featured melodies that incorporated bluesy notes (b3, b7, and notes that were in between the notes in the diatonic scale). The length was variable. There were 8-bar blues, 12-bar blues, and 16-bar blues. It was also common for blues musicians to stay on a chord for an extra measure or two if they wished to extend a phrase.
Later, the 12-bar blues form became standard. Here it is in its simplest form, in the key of C major:
Now, here's the part that confuses many beginning improvisers: This blues chord progression can be played in any musical style.
If you play this progression with a jazz beat, it's considered jazz. If you play it with a rock beat, you can call it rock. You can even use Latin rhythms, as did the jazz pioneer Jelly Roll Morton.
Generally speaking, it's called "blues" mainly when musicians who specialize in blues play it. That's why B.B. King can play a song and it will be included in a blues playlist, yet if The Rolling Stones play the same song in the same way it'll get aired on a rock radio station.
Musicians tend to label it according to the music they typically play. So a rock band might say "let's play a blues" and it will have a rock beat. At a jazz jam session, someone might say "let's play a blues in F," and everyone will play it in a jazz style."
Here's a video I made to show you how the basic 12-bar blues chord progression can be played in many different musical styles. Enjoy!
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