How Much Music Theory Do You Need To Know? (Bass Player’s Book Club #3.1)

Music Theory for bass players

How Much Music Theory Do Bass Players Need?

Music theory tends to be an area that confuses a lot of bass players, often resulting in the following questions: Do you really have to learn music theory? How much theory do you need to know? Is music theory really that important? Do you need special books on music theory for bass players?

Music theory can be summed up as a system for explaining why certain things sound good and others don’t; it’s a way of communicating the rules of music to yourself and other musicians. It’s the musical equivalent of spelling and grammar, giving us a framework that supports everything we do – putting theory in those terms makes it sound integral to our survival as musicians, but where should it sit on your priority list as a bass player?

Here’s my favourite theory-related question that helps to put things in context:

Have you ever been to a theory concert?

I thought not. Being able to play music is much more important than being able to talk about it in an academically correct way, but that’s not an excuse to avoid engaging with theory altogether.

The problem is that music theory in isolation is a dull, dry, dead thing; just like spelling and grammar. Now, can you become proficient in a language without knowing much about spelling and grammar? Of course you can. Is it easier to learn a language when you have some understanding of how it’s constructed and you can read and write it? Definitely. Will learning more about a language make you worse at it? I don’t think so, up to a point…

There’s an important distinction between knowing the rules of grammar and being able to employ them effectively. When you’re learning a foreign language it’s easy to become fixated on the nuts and bolts; verbs, tenses, cases and genders, but those things are all redundant if you can’t ask for directions when on holiday or understand a menu well enough to avoid ordering the local speciality of raw horsemeat.

Bass players are stereotypically lacking in harmonic knowledge, which is why we’re the butt of so many musical jokes. Broadly speaking, we fall into two categories:

  1. Facility without knowledge – being able to play well, but not understanding what you’re playing or why it works.
  2. Knowledge without facility – understanding musical concepts on an academic level, but lacking the practical skills to apply them in ‘real world’ situations.

The former is more common with beginners, the latter with more experienced players. Both are debilitating conditions.

What Music Theory Should I Learn?

So, how much music theory do you need to know? It depends on your musical goals. The problem with writing blog posts or preaching through YouTube is that it’s almost impossible to be specific; I don’t know what your musical background is, I haven’t heard you play and I don’t know what you’re aiming for. So, in order for this to have any merit whatsoever, we have to work out what we all have in common as bassists. Once you strip away personal considerations related to genre, technique, tone, and taste, we’re left with two responsibilities that everyone has:

1. Understanding which notes go into chords (and scales, but I would say that chords are far more important)
2. Knowing where those notes are on your instrument (regardless of the number of strings and frets your instrument might have and how it is tuned)

Those two things sound pretty simple, but it’s amazing how many players are deficient in at least one of these areas.

The Bassist’s Music Theory Road Map

There’s a lot of information out there to digest, so where do you begin? Let’s try to break it down into a logical progression. Some of what follows might seem unbearably patronising, but I don’t know what you know and therefore can’t assume anything (even bass veterans have gaps in their knowledge of the fundamentals).

What follows are the essential elements of music theory things you need to know to thrive as a bass player in any genre; there are lots of other concepts that might be useful to you depending on your unique musical situation, but those should be the icing on the cake.

The order of things that I suggest is not discrete; you don’t have to finish one area entirely before starting the next one.

Step 1.1: Rhythm

Being able to identify, categorise and communicate different rhythms effectively will immediately mark you out as being a well-rounded musician; there are an overwhelming number of players floating around with a weak sense of time and a vague understanding of rhythm – those who restrict themselves to TAB are more likely to be affected, as it absolves you of any rhythmic responsibility whatsoever.

Rhythmically speaking, you need to understand:

  • The rhythmic possibilities available when dividing up a bar of 4/4 all the way from one note to 16 notes (smaller divisions of time are available, but these aren’t a priority at the moment)
  • Dotted and tied notes (and their associated rests)
  • All possible combinations of 8th notes, 16th notes and rests that can occur within one beat


N.B. You don’t have to read music to do any of this, but it makes life a lot easier if you do.

Once you’ve got the hang of 4/4, you need to investigate other frequently occurring time signatures and rhythmic feels. In fact, you need to understand time signatures and many amateur musicians appear not to. Common scenarios like a 6/8 ballad, a waltz, a 12/8 shuffle groove, swing 16ths with straight 8ths all have different implications for how you subdivide the beat when you play.

When working on your rhythmic abilities it’s worth remembering this golden rule:

If you can’t clap something then you’ll never play it with any degree of understanding or fluency

Step 1.2: Pitch

Top of the list is learning the names and locations of every single note on your instrument; again, this is regardless of the number of strings or frets it may possess and how you tune it.

There are seven natural notes (A B C D E F G), four of which have additional enharmonic spellings (B#, Cb, E# and Fb) and five accidentals that each have two possible names (C#/Db, D#/Eb, F#/Gb, G#/Ab, A#/Bb)

That’s 21 pitch names in total. Pedants will bring up double sharps and double flats, but even I think that’s too much at this stage. Yes, they exist, but they occur very rarely and if you have a solid understanding of basic accidentals then seeing Fx (F double sharp) in a piece of music won’t give you a nervous breakdown.

How do you learn your bass fretboard in a logical fashion? A single string is the most straightforward way of seeing (and hearing) how music actually works on our instrument; using more than one string can tempt us into becoming dependent on finger patterns until everything becomes reduced to a shape.

Once you’ve got the hang of where the notes are, it’s time to start working on understanding the effect of varying the distance between them; this is the beginning of studying intervals, which are the universal building blocks for all genres of music.

Step 2: Intervals

Most problems that people have with harmony and theory stem from a lack of understanding of intervals. If you don’t understand how two notes relate to each other then it’s difficult to understand triads and almost impossible to really grasp 7th chords and beyond. This is also part of the reason that modes are so confusing – you can’t expect to understand anything about the lydian mode if you don’t know what a #11 is in the first place. People are always keen to skim over the fundamentals and skip straight to the hip stuff, but all that does is leave gaps in your knowledge and holes in your playing.

You need to know intervals from three different perspectives:

1. How they sound (ears)
2. How they fit on the fretboard (fingers)
3. How they’re spelled (brain)

Intervals are named based on their size in semitones and the number of scale degrees between the notes; you need to be fluent with all the intervals within an octave in every key to be able to survive as a bass player. Remember that for some intervals there will be more than one practical way of playing them depending on if they are playable on one string, adjacent strings, or non-adjacent strings.

Step 3: Triads

Once you’re familiar with intervals up to a fifth, then it’s time to start working on triads. Again, people get upset about 7th chords (not to mention 9ths, 11ths and 13ths) because they haven’t put the work in on understanding triads thoroughly enough.

What work do you need to do on triads? There are five types of triad to be acquainted with:

1. Major
2. Minor
3. Diminished
4. Augmented
5. Suspended (sus4 and sus2)

The first three arise naturally in the major scale (more on that later), augmented triads come from the melodic minor, harmonic minor and whole tone scales, and sus chords are an important sound that appear in a wide range of musical styles.

As with intervals, you need to know triads in three ways; how they sound, how they’re spelled and how they work on the fretboard. In order to become really happy with triads, you need to get comfortable playing them in as many ways as possible:

  • On one string
  • On two strings
  • Across three strings
  • Across four (or more) strings in multiple octaves

As with intervals, there will be multiple ways of playing each type of triad and you need to have two practical fingerings at your disposal.

Major triads are worth spending the most time on; once you’ve internalised the spellings of those then you can view the other types as being alterations – this makes the job of memorising somewhere in the region of 75 triads a little less daunting; you just focus on 15 major triads and work out everything else.

Inversions of triads are also very important if you want your playing to sound interesting. Learn how to voice triads and their inversions as chords, both in close position and spread voicings; this will really open your ears to more melodic bass playing possibilities.

Step 4: The Major Scale

To say that the major scale is important is a gross understatement, and really knowing the major scale in every key all over the instrument is yet another serious project, but because of all the work that you’ve already put into learning your fretboard and understanding intervals this shouldn’t be that stressful (famous last words…).

The most important aspect of learning about scales is about understanding the harmony that comes from them.

What happens when we build chords from the major scale in diatonic thirds?

We get this:

How much music theory do you need to know?

Three major triads, three minor triads and one diminished; these are the basic materials with which the bulk of the songs that have appeared in the pop charts for at least the last 60 years are built from. Getting a firm grasp of how these chords work together in a key to form chord progressions is the beginning of understanding functional harmony. If you don’t know how a chord functions relative to a key centre then memorising and transposing large numbers of songs for gigs becomes far more labour-intensive than it needs to be.

Step 5: 7th Chords

This is exactly the same as triads, but because we’re dealing with four notes we have a greater variety of chords:

1. Major 7th
2. Minor 7th
3. Dominant 7th
4. Half diminished
5. Minor major 7th
6. Augmented major 7th
7. Diminished 7th
8. Suspended dominant (7sus4)

The first four arise naturally if you harmonise a major scale in thirds, and those should be your main focus. Others come from minor scales and the suspended dominant is a common device in pop music when a composer wants tension but a dominant 7th sounds too colourful. All of these chord types can be thought of as a basic triad with either a major or minor 7th added.

Step 6: Modes

Modes are probably the most misunderstood aspect of contemporary music theory. As before, the majority of the confusion stems from a lack of understanding about intervals, both of the modes themselves and the chords that they function over. Instructional materials and some teachers often compound the confusion by not presenting modes in the best way.

Modes are derived by displacing a scale. The traditional introduction is to show the C major scale played from D to D, which gives the D dorian mode. You then get told that this is important because this is what Miles Davis’ ’So What’ is built on and that – get this – you can play over a ii – V – I progression just using one scale. Magic! No more thinking or musicality required, just plug in the scale and noodle away, instant jazz!

Whilst it’s true that you can play over Dm7 – G7 – Cmaj7 with just the C major scale I don’t think it’s the most musical perspective from which to approach things.

You really need to understand modes in two ways:

  • How they’re derived, i.e. which major scale they come from (‘derivative’ thinking)
  • How they’re constructed, which examines the component intervals of each mode (‘parallel’ thinking)

Parallel thinking is most useful when you’re learning the modes, because when you’re in a playing situation and someone says ‘oh, it’s a sort of A dorian thing’ then you need to immediately know that means that you’re playing a minor scale with a major 6th.

How do you work on parallel modal thinking? Divide up the modes according to the chord types that they function over:

Major 7ths: Ionian (you don’t really need much work on this because it’s the major scale) and lydian.

Minor 7ths: Dorian, phrygian and aeolian

Dominant 7ths: Mixolydian

Half diminished chords: Locrian

Modes are definitely not restricted to The Dark Arts of Jazz; unfortunately, this means that if you’re starting to glaze over and think that you don’t need to know this stuff because you’re not a jazzer then you’ve still got some homework to do.


Theory Books for Bass

Check out part 2 of this vouage into music theory for recommendations on the best music theory books for bass players: Bass Player’s Book Club #3: Harmony & Theory