How large is the number called a Googol? You could Google it, but I’ll just tell you: A Googol is 10100, or one followed by a hundred zeros. That’s about how many quarter-notes I’ve played in my life, or at least it feels that way. As I’ve walked my way through my career, I’m still outlining chord changes and providing a foundation for the music, often by playing the root of every chord on the downbeat of every bar. Walking bass lines remain an essential component of my musical life. Let’s look at a couple of methods to create beautifully constructed, practical, and musical-sounding bass lines without getting hung up on music theory. I’ll describe the basics of bass line construction, and then we’re off to the races … the walking races. Walking bass lines are constructed with steady quarter-notes and only three melodic elements: chord tones, scale tones, and chromatic passing tones (sometimes called leading tones). You can create a beautiful-sounding line in 4/4 meter by playing a chord’s root on the downbeat, followed by either chord tones or scale tones on beats two and three, and then a chromatic tone on beatfour leading to the next root. Wait, I said I wasn’t going to get into theory, so let’s forget all of that for now and start walking. Grab your bass! Example 1 shows a 12-bar blues in F. Imagine a nice, swinging groove in your head, and then play through the changes by thumping out the root of each chord on beat one of each measure. So far, so good … but what about the other three notes in the bar? Here’s the payoff for today’s lesson: If you outline the roots on the downbeats, all you need to do is lead into the next root with three chromatic passing tones [Ex. 2]. This method — playing the root on the downbeat, followed by three passing tones leading to the next root — works especially well on tunes where the harmony is moving around in intervals of 4ths and 5ths. The 12-bar blues provides the perfect playground for experimenting with this walking concept. Example 2 starts with the root of each chord on beat one of every bar. This outlines the root movement unequivocally with a pleasant feeling of forward motion. The listener hears the chords moving through the blues, because the bass is in their face on beat one of every bar. To lead into the next bar, simply play three notes (beats two, three, and four), chromatically approaching the next root. Theory nerds could debate all day about which chord or scale tones those three chromatic notes might describe, but a theoretical analysis doesn’t matter on a practical level. The proof is in the sound and feeling. The bass line has rhythmic forward motion, and the root movement is clear. Example 3 uses a slightly tricky variation of the chromatic approach heard in the previous exercise. I call this the chromatic upper double approach, but you don’t need to remember the term unless you want to start a heated discussion with someone on a bass forum. Th