I am an amateur bass guitar player. At some point I decided to do something about my lack of theory knowledge.

Now I know a few basic scales and can read sheet music in simple keys (from zero to one to two flats/sharps). I understand in general how chords are built on degrees of the scale and know some basic ones. I understand what V/vii etc chord means. I know where notes on the fretboard are located.

But when it comes to real practice with a band, I'm completely lost. I can't seem to apply this knowledge in the process and reduce to catching roots by ear and playing cliches which often don't match the key and chord, and as I discover it I start alternating them nearly randomly (with the scale in mind if I'm happy enough to see it on the fretboard) until it sounds OK.

How do I bridge the gap between the theory and practice and start using the knowledge?

  • 1
    I have always been frustrated at the lack of helpful explanation for basic music theory concepts. They throw around definitions and "explanations" that explain the symptoms, not the causes of each musical concept. I'll try to write an answer later today, after church, and give this question my best shot. Commented Jul 30, 2017 at 15:06

6 Answers 6


Let's take a step back and let's look at what you've learned so far and where it falls in the grand scheme of musical knowledge. Theory and notation typically get intermingled as the same so identifying where each is helps understand:

  • Scales (theory)
  • Reading sheet music (notation)
  • How chords are built (theory)
  • Roman Numeral Analysis (theory)
  • Notes on the fretboard (notation)

Notation is being able to read what someone writes down for music while theory is understanding it.

Where the theory comes intertwines with practice:

Theory helps you understand a piece. My collage bass instructor would say every time he got a piece he would "make it make sense to him". The deeper you look the more patterns you'll see and seeing the patterns helps you plan out what you can play and relate it to other things you've played before.

One example is C Dm G C represents the same basic pattern as E F#m B E. Recognizing it lets you do more with less as both are I ii V I progressions that you can use similar if not the same line on.

If you know the piece is in C major and the progression is I vi ii V, it opens a lot of possibilities because you know the general harmony and direction. On option is you could reharmonize and utilize secondary dominants i.e. I V/ii V/V V. Another is you know the general set notes will be used and the direction the harmony will go. Another thing is you can take similar functioning chords and replace them. I, iii, and vi, ii and IV, and V and viio have similar functions in a key. They aren't identical function, but they will help change the flavor a bit.

Chromaticism is also another big tool especially if you understand more advanced substitutions like tritione substitution. For example the progression above can become C Dm Db7 C so you can spice up a progression like the one above.

If you know nothing about the piece then you'll have to relies on your ear and play on the fly. If your ear is strong enough you'll be able to figure out and utilize theory, but it's dependent on your ear. Likewise if you just look at the notation and don't look any deeper you'll have to play exactly what's written. If you look deeper, the theory will open up options for you.

It's hard to see a lot of these patterns until you know how to look for them. I would suggest looking into what you're currently playing and common techniques first like the ones listed here and dissect them. Even just rehamonizing and playing the roots will open up a ton of new options.


The first, and most important thing:

Music theory is a set of tools to describe music. Theory does not dictate music, music dictates theory.

For example, a time signature on paper does not dictate how the tune will sound, the way the tune sounds will dictate how the time signature is written.

With this understanding comes the ability to apply music theory in a practical way. Music theory is not usually something you use while improvising, and it's not something you think about while performing, it's a language that you can use to describe what you did and to help understand why something sounds the way it does.

Instead of trying to learn music theory in a text book, I would learn it by use. Try stuff out. If it sounds good, find out why. It's all fine and good to know what a V/vii chord is, but you'll only use that knowledge practically if you need it for something.

Think of it like a box of tools. If you learn what they're called, what they do, it still won't be practical until you try to build a chest of drawers and you realize you need a way to cut wood, or hammer nails.

Of course, all of this is really easy to type up but harder for you to go out and do. As you go, try to identify different musical concepts that you see/hear. Almost as an aside, having access to a piano or keyboard will absolutely increase your understanding by leaps and bounds.

When you learn a new music theory concept, make sure you learn the "because" of it. Why does putting a Bb in a key signature make it F major? Why does slapping a capo on a guitar change its key? This is when connections start forming.

So in short, to make music theory "practical," you must have a use for it first. Learn music theory to solve problems that you encounter. See some of the answers here: How do we teach music theory well?


write musical analysis of your favorite bass lines, many bass players play Bach and other classical music which have plenty of writings of musical theory explaining them, train your ears to develop stable relative and absolute pitch and clear sense of harmonies, play a fretless contrabass, however it is an expensive and loud toy...

  • I've got a fretless bass which I converted from my old fretted one. It has fret lines, though.
    – olegst
    Commented Jul 31, 2017 at 19:52

@GeneralNuisance gets right to the point: music theory is a set of tools to describe music. But, would suggest a different emphasis on how to apply the theory in practice.

I say first analyze the music you play and listen to, and become skilled at identifying musical elements. Analyze the connection between the musical elements you can identify and the expressive effect they have. Be cautious about using theory to support the creative process to avoid theory becoming 'the rules of music.' The worst would be misapplying the theory you learn using isolated theory concepts in the wrong context. You might find something innovative... but you might also botch things up. I think it's better to take inspiration from your analysis of real music.

Also, don't mistake theory books for performance method or songwriting books. Theory books will tell what to name things. Theory will also explain why things work. Ex: the resolution of dissonance/tension gives a forward impulse to music. Method books will show you how to do things. Ex: play the chord root on the first beat of a bar in a walking bass line. Theory doesn't tell me to do that. A method book describing the style tells me. But, notice how we can only get the sentence in the method, by understanding the theory terms: chord, root, first beat, and bar.

Theory can illuminate the why? in the walking bass example. The root is played on beat one, because it most clearly identifies the chord and helps reinforce the meter. An approach tone is often played on beat 4 (4/4 meter) because a non-chord tone resolving by step to beat one of the next bar give the music forward momentum. Now that we have some musical context we can try to get creative with the application of theory: if the root on beat one is stable, maybe a rest on beat one and hitting the root on beat two an agitated or crazy feel. Try it and then analyze the result.


I'm a big fan of Ariane Cap's book "Music Theory for the Bass Player".


She has a full course for it as well (which you can find on her website). But for self-study, the book is excellent.


The funny thing is, it's a lot easier to understand music theory than it is to understand how music theory will help your playing. It follows that spending time understanding the theory is time better spent than time trying to understand how it's helping.

When you're with the band, just put theory out of your mind completely. If you have to think about it, then you're not ready to use it anyway, and it just clogs up what should be an enjoyable an creative endeavour.

Remember that music theory comes from how music is practised, not the other way round. It's far more valuable to notice that C, E and G sound great over C major chords, and that adding a B to that sounds markedly different to adding a Bb, even though they both work (depending on the context). The fact that you're then using C Ionian or C Mixolydian (which differ by one note, namely B/Bb) is only a way to describe what your ears have worked out already.

Play when you're playing, study theory when you're studying, and trust that they will indeed converge and enrich each other.

  • 1
    Please feel free to elaborate on the reasons for downvoting so that others may share in the wisdom. Commented May 17, 2019 at 3:14

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.