How to add bass to a melody

There are many ways we can start writing a song. We can start with a chord progression, we can start with the lyrics, or we can start with the melody. There is no right or wrong way to start it. Sometimes we have a melody and we want to add other components to the songs to get a full arrangement – for example, a bass line. So let’s see how can we add bass if we only have the melody of the song first.

How do you add bass to a melody

The melody is the top line of the song, and the bass is the bottom line. So there is no way to figure out the bass directly from the melody. Instead, you need to find everything else in between first. You need to find the key, then the chord progression, and the rhythm. If you have all these, you are ready to create a bass line for your melody.

Find the key

First of all, it’s worth finding out the key of the song. It makes everything so much easier if you know the key. Because both the melody and the bass is using the same tonal system. If the melody has a lot of movements, it uses a lot of notes, you have a relatively easy job to find the key. However, if the melody is very simple and static, using only a few notes, then it won’t be as simple to determine the key. On the other hand, if you have a simple melody, then you have more space for creativity because there are more ways of harmonizing it.

First, write down all the notes the melody is using. Ideally, if the melody is using a lot of notes, you should get a scale. And from the scale, you can try to reduce the number of options. For example, if the melody contains the notes F sharp and C sharp, then you know that it can’t be a C-major or a G-major key.

Many melodies use the notes of the pentatonic scale. The solmization of the pentatonic scale is “do, re, mi, so, la”. If the song is in a major key, then the tonal center is the “do”. For example, if the melody notes are D, E , G , A , C, then we know that the “do” is the note C, and the “la” is the note A.

Melodies usually end on the tonal center. So if the melody ends on the note C, then it’s in the key of C-major. If it ends on the note A, then it’s in the key of A-minor (Aeolian). But most of the time, you don’t even need to analyze the notes. If you hear a melody, you should be able to identify the tonal center just by ear.

Find the chords

The next thing you need to do is to create a chord progression. If you figure out the chords, then it will be relatively easy to find the bass. Because the bass line always follows the chords. So how do we figure out the chords? We already have the key, so first, we need to write down all the diatonic chords. These are chords from within the key.

For example, in the key of C-major, these are all the diatonic chords: C, Dm, Em, F, G, Am, Bdim. But here is a little secret: you can avoid the last chord because we usually don’t use it in songs. So there are really only six diatonic chords you need to focus on first.

Many times, melody notes use chord tones. What are chord tones? For example, in the case of a C-major chord, chord tones are C – E – G. But unfortunately, melodies use other notes too, so it’s not that simple to find the chords. Sometimes they avoid chord tones in the melody for a reason! In our songwriting course, I go into more detail about the connection between melody and chords. Try to find one chord to each bar. If it doesn’t make sense, use only one chord in every second bar.

Add root notes

Once you have the chord progression for the melody, you can start to create a bass line. The bass always follows the chords. And almost always, the first note of the bass is the root of the chord in each bar. So you can start by adding one bass note to the first beat of each bar. Always the roots of the chords. Of course, most of the time this bass line is too simple, but if you write a simple and slow song, you might not need to do anything else with the bass. Simple bass lines can work well in simple songs.

Consider rhythm

Now if you want to create a little bit more busy bass line, or even if you just want to make this a little bit more interesting, you need to play a little bit with the rhythm. While the bass almost always plays the root notes in the first beat of the bars, sometimes this first beat is anticipated. What does it mean? When you put the note one beat earlier, it FEELS LIKE the bass is playing on the first beat, or it feels like it should be on the first beat, but it comes earlier. This is called anticipation and it makes the rhythm more exciting.

How do you know what’s the right rhythm? First of all, just experiment and follow your ears. Use what sounds good for you. Secondly, I give you a formula for creating better rhythms in our songwriting course.

Should bass follow the melody?

The question is, should bass follow the melody? The short answer is: not at all! So how do melody and bass come together in a way that sounds good if they seem to be independent of each other? They sound good together if they follow the same systems. There are two “invisible” systems in a song that can be followed.

One of the systems is tonality (the key), and the other one is a rhythm system. Tonality is an invisible system because we don’t play all the notes of the key all the time. But both the melody and the bass (and other instruments) are using the notes of the system. That’s why they sound good together.

The other invisible system is rhythm. If the melody and the bass follow the same rhythm system, they will sound good together, even though it seems like they are completely independent. I call this system the Rhythm Code, and you can learn it from the songwriting course.