How I Created A  Blues Rock Line  At Random Using Bass Vocabulary...

And A 2 Chord Matrix!

Before I sketch out the process of creating this bass line at random, here's a video so you can check it out. Is it the greatest piece of bass playing in the world? Absolutely not, but it's a good example of 'meat and potatoes' bass playing, the kind of bass line that "working Joes" and "weekend warriors" have to crank out every night of the work in bars and rehearsals all over the world:


Here's how this was created.

First, I created a spreadsheet called a 2 Chord Matrix. So there are four chord movements in this standard 12 bar blues:

  • A7 to D7 (bars 1 to 2 and bars 4 to 5) - this chord movement is also the same interval for E7 to A7 in bar 12.
  • A7 to A7 (bars 3 to 4 and bars 7 to 8) - this chord movement is also the same interval for D7 to D7 in bars 5 to 6)
  • D7 to A7 (bars 6 to 7 and bars 10 to 11) - this chord movement is also the same interval for A7 to E7 in bars 8 and 11
  • E7 to D7 - bar 9 only

Second, for each column in the spreadsheet I added six piece of bass vocabulary ideas - I call them devices - that lead the ear from the root of the first chord to the root of the second chord to each column.

Third, I assigned each of those devices a number.

Fourth, I created a blank 12 bar notation and tab staff with the chord symbols written in.

Fifth, I went through each bar one by one and asked my 18 year old son (in the next room) to pick a number at random from 1 to 6. Each of those numbers corresponded to a device in one of the four columns on the 2 Chord Matrix spreadsheet.

Sixth, I wrote the appropriate device in played in pairs of swing 8th notes. The only - ONLY! - creative choice I made was WHERE to play each device.

Seventh, I printed that bass line out and then recorded it for the video you see above.


Here's The Takeaway From This

If you know your devices....

...And you know what devices connect which two chords together...

...And you know what genre specific rhythms you want to execute the devices with....



Knowing The Vocabulary Of Bass Is Not Just About Creating Your Own Lines....

...though that's a pretty powerful side benefit!

If you play in any kind of cover band then you have to play other bass player's lines. Unless you're playing in some really unusual genre, those lines will be composed of these units of bass vocabulary (devices).

So if you've practiced your devices thoroughly instead of having to learn a bunch of notes you can learn what devices are used. Which do you think is easier to learn: bar 1 is composed of C to C to E to E to G to G to C to C; or bar 1 is composed of a R-3-5-R device executed in 8th notes in C?

Not only is the second easier to remember, but if you turn up at a rehearsal and the singer had a heavy night and has a sore throat and everything has to be transposed a tone still only have to know it's a R-3-5-R device in 8th notes but the starting note is now Bb.


There's A Further Side Benefit Though

If you isolate a device to practice it thoroughly, not only are you working on developing your facility with the 'what to play' side of the bass equation, but you can also make those exercises do double duty and work on the technique - or the 'how to play' - side of the equation.

I'll demonstrate that in the next article - click the blue CONTINUE button below to check that out.


Paul Wolfe/




Previous Article In This Series

1. How Paul McCartney Learned To Play Bass:

2. Vocabulary Examples From The Language of Bass: