Bass Contour Rule 



Bass Contour Rule


Learn how to write better bass lines by creating melodic contours with 3rds and non-harmonic notes. But first… Tea!



Hello revolutionary music makers, we are Kate and Ray Harmony (AKA Revolution Harmony), and welcome to Hack Music Theory, the fast, easy and fun way to make music! If you’re new to theory, or if you just want a refresher, then read our free book "12 Music Theory Hacks to Learn Scales & Chords". It’ll give you a super solid music theory foundation in just 30 minutes. The free download is below. Enjoy!



Firstly, just to clarify. A fault is not a mistake! A fault is a weakness. In other words, an area for improvement. So, what’s the fault in this bass line? Well, to expose its weakness, let’s first explore its strengths. So, this bass line has a great rhythm, with syncopation to deepen the groove. It’s phrased well, which refers to where the music breathes through rests. It has a big range, which is the distance between the lowest and highest notes. And there’s plenty of movement between pitches to keep it lively. That’s a lot of strengths, so where’s the weakness? Well, believe it or not, there’s actually two weaknesses. Firstly, this bass line does not have a melodic contour. You see, a good melody doesn’t jump all over the place, like this bass line does. It should have a beautiful shape to it with relatively smooth ascending and descending lines, and the occasional big jump for interest.



And the second weakness in this bass line is that it does not contain any non-harmonic notes, which are notes that are not in the chord. When the bass only plays notes that are in the accompanying chord, it blends into those chords because there’s nothing that makes it stand out from them. But, when your bass plays non-harmonic notes, it separates itself from the chords. This ensures your bass is perceived as an instrument playing a melody, and not merely as a frequency.



Seriously, this is a massive problem in music these days. Bass lines tend to be nothing more than root notes, and when they do rarely move off the root, they tend to go to the 5. But, playing roots and a few 5s will not add a melodic layer to your song (which is how musical depth is created), all it will do is fatten up your mix by adding low-end frequencies. Your music deserves better, though. Your music deserves a bass that plays actual melodies with creative contours! And by the way, our example is in the key of D Dorian, which is all the white notes from D to D, and the tempo is 90 BPM.


FIX #1

Right, let’s fix this bass line now. And to do that, we’ve got an easy two-step method for you. Firstly, add at least one 3rd somewhere, because the 3rd of each chord is what creates its major or minor emotion. Over our Dm chord, we added the ♭3 (F). Over our Fmaj chord, we added the 3 (A). And over our Cmaj chord, we added the 3 (E). If all these numbers and flats are confusing, then download our free book below to learn all this stuff (and more!) through 12 simple hacks.


FIX #2

Right, step two is to add some non-harmonic notes, which are notes that are not in the chord. We’re using triads here, which are the most common type of chord, consisting of the 1, 3, and 5. So, the non-harmonic notes are the 2, 4, 6, and 7 over each chord. The non-harmonic notes we added are the ♭7 (C) over our Dm chord, the 7 (B) over our Cmaj chord, and the 2 (A) and the 7 (F♯) over our Gmaj chord. And if you’re wondering how we can have an F♯ in our bass line when the scale consists of only white notes. Well, that’s because F♯ is not in the scale, it’s what is known as a non-diatonic note. Unless you know how to play safely outside the scale, though, we definitely recommend staying in the scale for now.



Our Bass Contour Rule is that your bass line should have a big range with an interesting melodic contour that includes 3rds and non-harmonic notes. Because remember, if your bass is only playing the root of each chord and maybe a few 5s, it will only be adding low-end frequencies to your song, it will not be adding any musical depth!



Lastly, please be aware that the characteristics of a great bass line are slightly different to those of a great lead melody. For example, it’s normal for the bass to jump an octave or more, but that’s too big for the lead. If you wanna learn the characteristics of great bass lines, check out our tutorial: 6 Hacks for Better Bass Lines. Thanks for being here in the Hack Music Theory community, you are truly valued, and we're excited to hang out with you again soon!



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