Transposing: Changing keys on bass

Imagine you’re at a jam session. You have been waiting for an hour and finally you are called on stage. Of course you are beyond excited and can’t wait to start a wonderful musical conversation with all these cool new musicians.

After a quick chat with the band you have all agreed on which song you all know how to play, but just before the drummer decides to do the count-in, the singer all of a sudden shouts: “Oh by the way, we’re not playing the original key of G, it should be C#, no problem right?”

While you hear the sound of two drumsticks clashing together four times, your life flashes before your eyes. You are asking yourself if you were already covered in sweat five minutes ago. Miraculously, you succeed in playing a C# on the first downbeat. Victory, yes! But you soon realize there’s no time to feast. There is a chord change coming up!

Easy techniques for playing in a different key

G           |C          |EMI        |D          |

The little four chord sequence notated above is a transcription of Tracy Chapman’s “Talkin ‘bout a Revolution” in it’s original key, G. This song will function as a common thread throughout this article.

In this fictional jam session you have already succeeded in transposing your G to a C#. To make sure the rest of the song also sounds appealing, the next step is to also raise or lower the rest of the chord(tones) with the same interval.

Maybe now you’re thinking “Okay, from G to C# has been transposed by one, two, three, four and a half steps, I should do this with all my chord tones!” Of course you are right in thinking this, but the problem in this thought process is that it takes too long when you are in a live-situation. As you probably experienced, the more steps your brain has to take, the longer it takes.

In this article I will show you two fast and easy techniques that you can use depending on your knowledge of theory and your instrument. Guaranteed happy faces on stage!

Method 1: Relative positions

A great thing about the bass guitar is the fact that it’s such a visual instrument. Instead of approaching every chord separately and to remember it accordingly, looking at the neck of your bass can give you a great visual representation of the relationship between chords.

Remembering the shape on your neck can give you a great roadmap to where the different chords are, and can help you greatly when transposing on-the-fly.

The picture above represents the neck of your bass from the point of view of the player. The lowest line represents the E-string, the blue circles represent the notes you should fret. For example, the lowest blue dot on the image represents the third fret on the E string which is a G. Looking at this picture, it is easy to see the relationship between the notes.

Playing the changes as in the song by Tracy Chapman, your roadmap would be to play the third fret on the E string (G), play the third fret again but on the next string (C), then move up 4 frets to the third chord (Emi) and move back two frets to the last chord (D).

One of the easiest way of transposing a song is just moving this whole shape and playing it somewhere else. In this case we are moving the shape with the goal of having the lowest note on the C# as visualized in the picture below.

Theoretically what you’re doing is fine and you will definitely notice that it doesn’t sound bad. What you probably will also notice is that some of the notes you are playing are pretty high on the neck or in a high register. Seeing as one of your most important tasks as a bass player is to lay down a solid foundation, most bass players prefer to play their notes in a lower register. This is where octave shapes come into place.  

You can play the same note an octave lower by simply moving it two frets downs and two strings up. In the picture above you can see the old (pink) note connected to the new (blue) note with an arrow. It’s up to you to decide when to play the higher or lower not. Lower notes usually add beefiness and depth while higher notes can make things sound more airy and lighter.

So a step-by-step plan for applying this method:

1. Create a roadmap and visualize the shape in which the chords are related to each other.
2. Move the shape on the fretboard starting on the fret where the new key is on the neck.
3. Be aware in which octave you want to play a note and choose accordingly to the sound you think the song needs. If you choose to switch octaves, use your octave shapes.

Methode 2: Chord functions and the Nashville Number System

A different method is applying the Nashville Number System. This method revolves around giving every chord a roman numeral, which defines the function of the chord inside the key. “Sounds pretty complicated!” Actually it’s not complicated at all.

To make sense of this concept, let us look back at the example of Tracy Chapman’s talking about a revolution. The key of Tracy’s song is G. This means that the song is based around the G major scale. As you probably know, the G scale consists of:

G – A – B – C – D – E – F# – G

By using the Nashville Number System we give every note in this scale a Roman numeral. So we would give G the Roman numeral I (one), the A will get the Roman numeral II (two), the B will get the Roman numeral III (three), C becomes IV (four), etc.  

If we would apply the system to Tracy’s song, instead of:

G              |C             |EMI           |D             |

We would get:

I              |IV            |VI            |V             |

Now we know which function every chord has inside it’s key, finding the right fret to play has just simply become a matter of knowing your intervals well. If you know where you can find your perfect 4th (IV), perfect fifth (V) and your major sixth (VI), any key is just going to be a piece of cake!

Pro tip: Make sure you know how to find your intervals in different places on the neck/learn different shapes. Also, learn to find the interval below, as well as above the root note. For example: You can find a perfect fifth below the root on the same fret and a string higher, or above the root when you move two frets up and move one string lower.

So a step-by-step plan for applying this method:

1. Don’t remember a song by remembering the chords, but by remembering the chord functions in the key.
2. Know where your intervals are in relation to the root so you are always aware of where your next chord is.

The best method

The first method I suggested is mostly intended for bass players who are still working on their theory. It’s an easy and fast method which allows on-the-fly transposing without having to think about every chord and without having to learn a lot of theory first. This method also complements the second method because it forces you to think about visual relationships between chords. If you know that the next chord is a whole step up from the previous chord, you won’t have any trouble finding it in your new key.

I can image that the second method sounds a lot more abstract than the first one and thus a lot less appealing. As you progress more as a musician though, your ears will get better and better over time. Without realizing it, you will start recognizing these chord functions. Familiarizing yourself with the concept and being aware they exist will open a whole new world for you.

Also when you play a lot of sessions and play songs in different keys than the original on a regular basis, you really need to be a fast transposer and don’t have the luxury to think about it for a long time. The Nashville Number System allows (and was actually designed to allow) you to transpose without any extra thinking steps.

Chord functions can also really help you when explaining a chord sequence. It makes things a lot easier if you are able to tell someone that the chorus is a II-V-I (two, five, one) or that the bridge starts on the IV chord. You could even cue your band members from across the stage by putting up four fingers to indicate that a chord change to the IV chord is coming up. You should always be aware which finger you use when referring to the I chord though.

If you enjoyed this article you might also enjoy How to not suck at a jam session.

I hope you found this article helpful! Let me know in the comments what your thoughts are and if you have any questions or suggestions.