A more open way of playing intervals is by using sixths. The mixolydian scale is harmonized by adding a second note that is a sixth higher then the original note.
The Bb mixolydian scale has these notes:
| Bb | C | D | Eb | F | G | Ab | Bb |
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 |
When you add a sixth, you get these intervals:
Bb-G, C-Ab, D-Bb, Eb-C, F-D, G-Eb & Ab-F.
Hey, you'll never remember this if you're life depended on it. Look at these examples to help you out. Focus your riffs on these positions and vary them to your liking.
Intervals Sixths Ex 1 - CD 12 (mp3 click here : )
The tonic of the chord is the first note you play. Move them up
5 frets to get the Eb riff (the IV chord) and another 2 to get the F riff (V
chord).
Or play the IV chord riff like this:
Intervals Sixths Ex 2 - CD 13 (mp3 click here : )
Move the same riff up two frets for the V version
Move these riffs up 5 and 7 frets to get the IV and V version.
We've added a little bass line to the riff and expanded it with a new position. The IV and V position that we've used up the neck can also be found a lot closer. It sounds more like an accompaniment in this position and stays out of the way of the soloist or vocalist.
The first note in bar 5 is the tonic of the IV chord. Position
all other notes on the IV riff based on that note.
Do the same thing with bar 9 and the V chord.
Note the progression in bar 4. It leads you smoothly from
the I to the IV chord (inner logic again).
The pattern of the riff is continued through bars 9 and 10, all through the
chord changes. In the last bar, we're using a chromatic walk up to the V chord.
By now you've figured out that there are at least two positions
for playing sixths: tonic on the E string and tonic on the A string.
This means that if you move the IV position riff from the last example up 7
frets (or 5 frets up from the V riff), you'll get a new position for riffs on
the I chord. The tonic Bb can be found on the 13th fret of the A string. All
riffs are played relative to that tonic.
Note: inner logic with sixths riffs
As with thirds, there is an inner logic to playing sixths over a blues chord progression. Because you're using notes from the mixolydian scale, you've got to change scales when you move from chord to chord. Listen to Example 5 to see what you can do with it.
In the beginning it's pretty hard to immediately see which
sixth form to use. Stay with it and you'll get the jist.
First, always look for the tonic of the chord; all the notes you'll want to
use are relative to that note!
Intervals based on 1st Position Blues
These next examples are a mixed bag. They use different intervals taken from the blues scale (first position) and mix them up with intervals taken from the mixolydian scale. Move them up 5 frets and 7 frets to get the corresponding IV and V chord riffs.
Intervals 1st Blues Pos Ex 1 - CD 17 (mp3 click here : )
The sliding up to and hammering on to the major third of the scale (6th fret of the 3rd string) makes it sound very bluesy. The first time you use it with a major third interval, the second time it's a tritone.
This one uses the flat 7 and the 6th of the scale.
One with a particularly mean interval at the beginning. To add tension, give it a twist by pushing both fingers up a bit. This is the blues.