This is one of the first in a series of online guitar lessons I'm writing for my students here in Vancouver. Exploring the modes can open up lots of new harmonic ideas and opportunities. This lesson is not for beginners, mind you. You'll need to have a grasp of basic music theory before diving in here.
The Dorian Mode Explained
The Dorian mode is the second mode of the major scale. You could think of it this way: In G
major, the Dorian mode would be A Dorian, because A is the II of G major.
G A B C D E F#
A B C D E F# G
The Dorian mode has a unique sound that is similar to the minor scale, but of course it has some differences. But remember for now, just like the minor scale, it has a minor third, giving it a minor-scale sound, or somewhat sad sound.
Root 2 m3 4 5 6 m7
Another way to think of this is to look at the series of whole and half-steps between each degree of the scale. In the figure below, the "W" stands for whole steps, and the "H" stands for half-steps.
Root W 2 H m3 W 4 W 5 W 6 H 7 W
To put that in an easier way to memorize, I think of the Dorian mode as having a Minor Third and a Major Sixth. These two tones are what I find are especially unique about the mode.
Some people like to think of Dorian like this: Take a major scale but flatten the 3rd and the seventh and there you have Dorian. Either way, you get the same result.
The Dorian Mode on Guitar
Here is my favourite shape for playing the Dorian mode on the guitar. Notice that the root is at the bottom, first finger.
The best way to memorize any scale on guitar is to memorize the visual shape it has on the fretboard. This one is fairly easy to memorize.
Whenever you memorize scale shapes on the guitar, be sure to memorize where the roots are -- not just the root at the bottom. Notice that there is also a root at the 7th fret of the D string.
Dorian and Minor Pentatonic
An important thing to notice about Dorian is that the Minor Pentatonic scale fits right inside Dorian. Indeed, this particular Dorian shape (illustrated above) fits directly on top of our easy A minor pentatonic shape from the fifth fret.
A Minor Pentatonic:
A - C D E -- G
A B C D E F# G
Try playing A Minor Pentatonic, and then A Dorian up and down. You'll notice how they fit together. Indeed, when playing in Dorian, we often revert to our well-known favourite Minor Pentatonic licks since both with work nicely in A Dorian.
Using the Dorian Scale
Dorian works great for both blues and rock and there are loads of songs that ideally suited to it. The most obvious example are songs by Carlos Santana. He made great use of the Dorian mode in lots of his soloing, mixing both classic A Minor Pentatonic licks with melodic A Dorian melodies.
The song "Oye Como Va" has just two chords for the most part: Am and D7. That chord progression is ideally suited to A Dorian.
Think about it this way: if the parent major scale of A Dorian is G major. That's because Am is the II chord in G major. And indeed this chord progression is like II then V over and over in G major -- except we never play a G major chord! So it's A Dorian all the way.
How to Recognize Dorian
It's one thing to analyze all the theory here, but it's another to recognize when you can actually play the Dorian scale on a song. I always look for this chord movement: A minor chord moving up a fourth to a major chord.
Another way you could think of it for us guitar players, a minor chord, then a major chord up a string, same fret. So an Am chord has it's root on the fifth fret of the 6th string, then a D major chord has it's root the same fret just up a string, so fifth fret, 5th string.
Examples: Am to D or Bm to E or Cm to F
The second chord could also be a dominant chord.
Examples: Am to D7 or Bm to E7 or Cm to F7
Also, try to remember that Dorian is the second mode. So I just think Dorian is II.
Another common Dorian vamp is the Im to IIm, back and forth. Think Van Morrison's Moondance verse. It goes Am - Bm - Am - Bm etc. When you see those two minor chords that are a whole step apart and they vamp back and forth, it's likely a Dorian vamp.
It's not necessary for an entire song to be in the Dorian mode for us to claim Dorian or to use the Dorian scale. It's very common to have a section of a song in Dorian. For example, if a song vamps Am to Bm for a long time, but then finally goes to a G major chord in a chorus. We could argue that song is in the key of G major. But since the verse never resolves to G, arguably the verse is A Dorian because it doesn't have a home chord of G major.
You could also play the Dorian mode over the I, IV, and V chords of the I-major key it
is derived from, especially if you anchor those chords with the root of the Dorian mode.
For example, in the key of G, the chords might be:
G/A D/A C/A D/A
Or more commonly, you could just think of using the Dorian Scale any time you have a IIm chord in the major key, especially if you have it for a few bars stretched out.
So for example, in the key of G major, you can play A Dorian over the IIm (Am) chord. This will still essentially sound like G major over all -- remember that G major and A Dorian have the same notes. But thinking of A Dorian over the Am chord will help you to keep the sound at that time rooted in the Am chord and not thinking of G as your root.