The Most Important Music Theory And How It Helps You Play Better

If you know some Simple and Basic Music Theory but you know it well, then you can use that to understand most harmony and find a lot of great sounds for your solos. I think you will be surprised just how far you can go and how much you can do with a few really basic things, but you do need to work on the right things.

What is Music Theory

First I want to look at what Music Theory is and how you can use it, because I think, that is often misunderstood, which makes it more difficult than it has to be, and you might not realize that you already know a lot. Music theory is just like playing music: If you really know the fundamental things, the rest becomes a lot easier.

Remember that you can use the chapters in the video to go back to something or skip ahead if you already know it.

One of the most important things to realize is that you use Music Theory to describe and understand music. It really is about putting describing what you hear. Sometimes people want to make it a set of rules that tell you what you are allowed to play, but that is not really how it works.

Rules might seem useful as a way of learning, but as you will see, being able to describe and understand what is going on is a lot more useful, and in the end, there are no rules anyway.

Let me quickly show you how describing music is incredibly useful an example from a Blues classic.

How Music Theory Is Useful

let’s take this example of an Eric Clapton phrase from the song Hideaway.

Example First Phrase

Level 1 – Clueless

If you don’t know anything about music theory, then he is playing magic notes that sound amazing.

Level 2 – Scale and Chord Progression

If you know a little bit more then you know that the song is a Blues in E, and he is playing the E major pentatonic scale.

Level 3 – Understanding the phrase

if you want to learn to play it then it is useful to realize that he is starting on the 5th and then the next part is him running up the scale ending with bending the 2nd up to the 3rd.


So level by level you go from “Magic notes that sound amazing” to “a scale run with a bend in the pentatonic scale”, and it is obviously easier to learn how to play it if you know that it is this scale with a bend on this note instead of memorizing a lot of magic notes.

And all you do is recognizing and describing what is going on. That is how Music Theory is useful.

#1 The Major Scale and The Notes In It

The first and most basic thing you want to know is something that most of you probably already know. The major scale, how it is constructed, and the notes in it. Really knowing this means that it is a lot easier to figure out most other things you’ll come across so this is incredibly important.

If you construct a major scale then you start with a root note and move up in intervals of whole and half-steps.

The formula is 1 1 1/2 1 1 1 1/2

For a C major scale:


You want to know the notes in there, if you have to use a formula to figure out the notes then you don’t really know this. That is too slow for you to use it when you are playing.

You also want to know this in all keys, especially the ones you play in., in fact, those are the ones you want to start with.

Besides knowing the note names then it is very important that you know the degrees of the scale, you will see why in the next section of the video.

1 2 3 4 5 6 7

How Well Do You Need To Know Scales?

Having a solid overview of the scale notes will make it a lot easier to analyze chords or solo phrases which also helps you figure out what is happening in a solo you transcribed and how you can start using the same things in your playing. If you have to calculate what notes are in the scale that quickly becomes almost impossible. If you know them really well then it is like a language you speak. Something you can use and get from information from.

In the long run, you want to know all the scales by heart so that you don’t have to think about what notes are in there, simply because this can be the foundation that you build everything else on, as you will see in the rest of this video.

#2 How To Construct Chords

When you improvise in Jazz then usually you are using chord symbols as a guideline to shape the improvisation. So you need to be able to translate the chord progression to something you can use in a solo, and knowing what notes are in the chords is a really good place to start.

There are two ways you can approach this, you can take a root and then construct the chord from that, just using intervals, but often I find it is better to start immediately by learning the chords you find in a scale since those are the chords you will also come across in chord progressions, and they are connected in a lot of useful ways that you can also use in solos.

From Scale To Harmony

Constructing chords in a scale is pretty simple. A chord is a stack of 3rds and you have two main types of 3rds: major which is 4 half steps (Play) or minor which is 3 half steps(play)

If you construct a triad from C in the C major scale then you start with the scale

the scale: C D E F G A B C

and from C you move up a 3rd to E, and from E up a 3rd to G. – C to E is a major 3rd so it is a major chord. E to G is a minor 3rd. C E G is a C major triad where C is the root, E is the major 3rd and G is the 5th.

If you create a triad from the next note in the scale D then you get D F A which is a minor 3rd followed by a major 3rd from F to A. This is a Dm triad with D F A is root, minor 3rd and 5th.

All the triads are major or minor except the one on the 7th note in the scale, in this case that is B D F, here you have a minor 3rd from B to D and another minor 3rd form D to F. The interval from B to F is called a diminsihed 5th and different from the one from C to G which is called a perfect 5th, and this type of triad is called a diminished triad: Bdim

In this way you can construct the diatonic triads of a major scale:

C Dm Em F G Am Bdim

Remember that this order of Major, minor, minor, major, major, minor dim, is the same in all major keys,

so if you have Eb major:

Scale: Eb F G Ab Bb C D Eb

then the triads will be

Eb Fm Gm Ab Bb Cm Ddim Eb

This is something you want to automatically know that for the keys you play in, if not just all keys, but keep in mind that this is really just a different way of seeing something that you already know because you know the scale.

Triads are a great resource for solos or for comping, so this is more than just theory, a line using Em and G major triads over a Cmaj7 sounds like this:

and later I will show you how to find those triads for a chord, but first, you need some 7th chords which is, sort of, the basic chord type in Jazz.

Diatonic 7th Chords

You already know the triads and all you need to do to get the 7th chords is to add a 7th.

For the major scale you only have two types: maj7 and b7: For C major: C E G, if you add the 7th: C D E F G A B , you get C E G B. The interval from C to B is a maj7th, written as Cmaj7.

Notice that the 7th is just one step down in the scale, a maj7th is a half-step down, and a b7 is a whole step down.

An example of the b7 is found on the next chord, Dm: here you get D F A and add the C to get a Dm7 chord.

The 7th chords in C major will give you:

C Dm Em F G Am Bdim

Cmaj7 Dm7 Em7 Fmaj7 G7 Am7 Bø

So you get a maj7 on C, a b7 on D, and also on E giving us Em7, on F the 7th is E giving us Fmaj7. The 7th on G7 is an F giving us a major chord with a b7 called a dominant chord. A to G is a b7 giving us an Am7. The B dim also has a b7 from B to A so that is a Bm7(b5) also sometimes referred to as B half-diminished.

Now you have the chords in a scale and you can find them in any key, but again this is stuff you really just want to know. Try practicing the diatonic chords in all keys and also move simple progressions around like a II V I or a I VI II V

When you improvise in Jazz then you usually take the chord and find material that fits on that chord. Let’s look at a great way to find a lot of material in the form of triads and 7th chords for any chord.

#3 Finding More Arpeggios (Crazy simple)

This concept is really simple and is something you can mess around with by just writing out a scale in a different way!

The basic idea is that if you are improvising over a chord then you can use the scale and the arpeggio of the chord, but you need to have more options than just the scale and the arpeggio, and if you check out solos from great Jazz players then you notice them using a lot of other things as well.

These arpeggios and triads they use are not coming out of thin air, it isn’t magic (It is NEVER magic when it comes to note choice), and you can easily use the music theory I covered in this video to find a lot of options.

Let’s first look at the scale in a different way:

Usually, you write the scale out in steps, so C major is C D E F G A B C but now you want to find triads and arpeggios, and they are built in 3rds so it is practical to write the scale as stacked 3rds like this:


I wrote out a few octaves because that is easier.

Let’s say you have to improvise over a G7. You just need to find triads and chords that have a lot of common notes with G7. Because G7 is what the rest of the band is playing, and if you play those notes that sound good.

So now, instead of G7 and the scale you have

G7,Bø and Em7 + Em, G, Bdim and Dm triads

Each of these arpeggios are triads are really just a very flexible melody that you can work with and you can combine them as well to get an incredible amount of possibilities in your solo.

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