Minor Scale & 6th Mode Explained: Guitar Theory For Beginners

By Christoper Horton •  Updated: 05/29/22 •  18 min read

We have talked a lot about music theory for guitarists, and so far we have stuck to the Major Keys and Modes. Today we look at the Minor Scale for the first time, and talk about how to use it!

Easy Theory For Guitarists: The Minor Scale

We have been exploring some basic music theory for guitarists lately, and have seen a lot of positive response. Thank you, first and foremost! Learning music theory seems really daunting at first, but we are aiming to make it as quick and painless as possible. Because let’s be fair, as guitarists we are probably the most guilty when it comes to lack of musical knowledge. I mean, its a meme at this point.

But that’s exactly what we are trying to put an end to. If you checked out our article about learning the fretboard then you are already ahead of a lot of guitarists! Then we tried to ease you into basic theory the most simple way possible. Finally, we have learned about the Major Scale and Ionian mode, and why it is so important when it comes to theory for guitarists. Today, we are going to do the same thing again, just with the Minor Scale and Aeolian mode.

In the other articles we pointed out the irony of music theory for guitarists, since to be fair, learning theory on guitar is actually much easier than some other instruments. The way the fretboard is laid out, the guitar is just begging to learn theory on! We also talked about the myth that learning theory will ruin your creativity, and how absolutely ridiculous that is as a concept. Knowledge is power, and it will only make you a better player.

So today we are going to dive a little deeper into theory, and learn one of the most common scales for Rock and Blues guitar solos. You have definitely heard this scale a million times, and it and is used so widely because it sounds very serious, and dramatic. The Minor Scale is particularly popular in heavy music of all genres.

So let’s dive in, but before we do…there is a little bit that you need to know ahead of time. You really need to know Intervals and the numbers associated with them. If you already checked out our article on the Major Scale, then you are familiar. If you haven’t, then now is the perfect time to learn. The Numbered Intervals are essential when learning music theory for guitarists. I promise, this will only hurt for a moment. It hurts me, more than you and if you already know this you can skip it.

This is a “Hands On” type of lesson, so go ahead and grab your guitar, get tuned up, and get ready to learn some basic music theory for guitarists!

Easy Theory For Guitarists: The Intervallic Fretboard

Numbered Intervals are kind of like the secret code that makes everything make sense when creating scales and chords. It is definitely important to know the notes themselves, but understanding Intervals is going to be essential to learning theory for guitarists, and basic music theory in general. So in case you missed it last time:

Intervals are also known as diatonic numbers in basic music theory. This is where guitar might actually be an easier instrument to learn music theory with, because of the way the fretboard is laid out. This is because numbered intervals are pretty straight forward when you are looking at the guitar’s fretboard. Each scale that you learn is made up of these intervallic numbers. For reference, we can take a look at the Interval numbers on a guitar fretboard:

basic music theory

This is a numbered Interval chart in the Key of F. The notes marked as “R” are the Root Note, which is F. Every R that you see, is an octave of the Root Note, since the Root Note always repeats in these same increments, with the one at the bottom being the lowest note. Take your guitar right now and hit an open string, then hit the 12th fret. That’s an Octave, the same note but higher in pitch! The official definition is:

Octave: A series of eight notes occupying the interval between (and including) two notes, one having twice or half the frequency of vibration of the other.

These series of 8 notes all have a Interval Number, and that is where we get into the real function of Intervals. Each step/fret/note between your Root Note and the octave has a different number, but the Root Note is always “1“. These numbers are important when looking at scales, because it will help you understand what makes the Quality of a scale. Adding sharps and flats will change the Quality of a scale or chord. The C Major Scale for example, has no sharps or flats. The number system is easy to remember:

Theory for guitarists is easier because of the frets already being laid out like this. We already understand what sharps and flats are, and Numbered Intervals are really no different. But instead of being sharp or flat notes, they are the scale and chord positions on the fretboard. This is usually where theory for guitarists gets a little muddled up. But it really is easy to learn!

I recommend saying the Interval Numbers out loud when playing a scale or mode. This gets you familiar with the sound of each Number. It is even better if you can sing them, even if you’re not a singer!

Numbered intervals are absolutely essential to understand when it comes to building scales and chords. If you compare the names with the picture example above, you can see how these work. The picture shows you the intervals in the key of F, but this is the same no matter what the root note is. For example, move one fret up from the Root Note anywhere on the fretboard, and you are on the Flat Second, no matter what key you are in.

Looking at the fretboard as a series of numbered Intervals can take some getting used to, just like learning the notes of the fretboard. I know, it seems like more work since you already learned the notes and NOW they have numbers too! But as you dive into more basic music theory, it will start to become almost second nature when you look at scales. Music theory for guitarists is actually not that hard when we break it down to simple numbers.

Music Theory For Guitarists: The Natural Minor Scale

Alright, if you are still with me it is finally time to check out the scale itself. In the previous article I mentioned that the Major Scale is usually front and center in compositions. From film soundtracks to modern bands like Polyphia, the Major Scale is everywhere. But when you need a change in mood, the Minor Scale is the first place you turn to as a songwriter. This is especially true though when we are talking about theory for guitarists. Because as guitar player, we all gravitate to the Minor Scale.

So what is the Minor Scale, and how does it work? Well first, I think we should take a look at the Minor Pentatonic Scale first. I think if you play any form of heavy music or Blues you are probably very familiar with this Pentatonic Scale. For the sake of continuity, we are going to be looking at these scales in the Key of C, just like we did with the Major Scale.

Theory for guitarists
C Minor Pentatonic

Yeah, if you play any type of Rock music, chances are you already know this in some capacity. The is the C Minor Scale in the most basic form. If you take notice to the Intervals compared to the Major Scale we already discussed, there are some flats and sharps present now. Now, I hate to drop this on you so suddenly, but there are actually THREE different versions of the Minor Scale! While Major really only has the ONE. So first, we have to make the Natural Minor Scale, by adding some Intervals to that Pentatonic above.

For the Natural Minor scale, you are going to need to add some notes to that simple Pentatonic above. But just like the Major Scale, its easy if you know which Intervals make up the Natural Minor Scale. They are as follows:

Just to practice your Intervals, I want YOU to add those notes to the C Minor Pentatonic. You are definitely missing some notes in that C Minor Pentatonic in the picture above. But what is missing from the scale? Time to play detective, since you know the “code” of the Numbered Intervals. So try to add the Second, Perfect Fifth, and Flat Seventh that are missing from the C Minor Pentatonic. You should get something like this:

theory for guitarists

Did you fill in everything correctly? If you did, congrats! Its ok if you cheated too. The Natural Minor Scale is used all the time in all kinds of music, but you really hear it a lot in Rock music. The reason for this is the sound of a Minor Scale progression. Every scale and mode has a “character” to it, and a personality unique to each one.

The Natural Minor Scale is super versatile. It can sound very “dramatic” or even “sad” at times. It really depends on how you use it. Just like the Major Scale is used in films for the main bombastic theme music, the Minor Scale is used to convey a change in mood. Usually to something darker, or sad. But it can depend, on how you use it.

When we talked about the Major Scale, we mentioned John Williams and his “Star Wars” theme, and how the Major Scale makes it sound big and bombastic. The opposite of this would be someone like Hans Zimmer. If you listen to any of his film music, you will notice that he uses the Natural Minor Scale a LOT. That’s because it can sound dark, and moody. Check out his soundtrack for the newest “Dune” movie, and you will hear the Minor “sound” in all its glory (And all 3 versions!).

But what about the 3rd fret on the guitar? Isn’t the C note located there as well? It is, and you can definitely play the Natural Minor Scale starting on the third fret. We did this with the Major Scale too, and that lesson taught us that the Interval Numbers are the same everywhere. You just apply the same Interval Numbers to the scale for two octaves, and it should come out like this:

theory for guitarists

Just like any scale pattern, you can take those Interval numbers and apply them anywhere on the fretboard. You can find the Root note anywhere on the guitar, and apply the Interval Numbers to the scale. You will still have Natural Minor, just in a different octave! If you had a guitar with 100 frets and 100 strings, this would never change, no matter where you played the note. 7 string players know what I’m talking about!

But wait, you just totally learned something else while you were practicing Natural Minor. You also learned a MODE.

Music Theory For Guitarists: Aeolian Mode

Just like the Major Scale is the same Intervals as Ionian mode, Natural Minor is also Aeolian Mode. Look at you, accidently learning another Mode! Aeolian Mode is the 6th mode, and that will be important later when we discuss modes in detail. But if the Natural Minor Scale and Aeolian Mode are the same, then what’s up with the name? Why not just stick to calling it “Natural Minor”?

Again, we can blame those sneaky Ancient Greeks… and probably their wine habits again. Just like the Ionian counterpart sounds happy and celebratory, Aeolian dominant compositions usually sound a little sad and dark. Aeolian is usually used when you want to convey longing, or melancholy. It is the perfect opposite of Ionian to even the most untrained ears, and that’s why it is used to change the “mood”.

But this is just the FIRST Minor Scale, next we add in an Interval Number to change it up a little. Let’s check out the Harmonic Minor.

Music Theory For Guitarists: Harmonic Minor

So we totally get the idea of Natural Minor right? In comparison with the Major Scale, the Natural Minor is the logical counterpoint when it comes to theory for guitarists. The Harmonic Minor is very similar to the Natural version, it still has a Flattened third note, which gives the scale its signature sound. So what are we changing to make it “Harmonic”?

We are going to take that Flat Seventh, and raise it by a semitone to just a regular Seventh. The Harmonic Minor Scale is used best with songs that are in a Minor Key. But in Classical Compositions, you sometimes hear the Harmonic Minor played over the V Chord, and this just switches up the overall “flavor” of the composition. This works in the I IV V Chord Progression we have discussed before, as well! Let’s take a look at the scale:

theory for guitarists

As you can see, all we did was change all of the Flat Sevenths, and raised them up a semitone to a Major Seventh. Try out this scale, back to back with the Natural Minor on your guitar right now, and I think you will be able to hear the slight difference. These are some good examples if you want to check them out:

Basically, the Harmonic Minor is the “Sound Of Rock And Metal”. This is because it is so versatile, musically. If you are still wondering exactly where Harmonic Minor fits in, just listen to any Rock music from the 90’s. Heavy music and the “grunge” music of that era used the hell out of Harmonic Minor, because it can be played effectively:

Harmonic Minor is used in a ton of guitar solos, but it is also used to construct vocal melodies. This is because the Major Seventh that we added to the scale causes some serious tension. I use Harmonic Minor all the time in my own music, for that very reason. The tension it causes sounds very dramatic. Slash is guilty of using this scale to death with his solos, but it has become a part of his whole schtick.

So next time a solo comes up in a heavy song, take notice to the scale they are using. Chances are there is some Harmonic Minor in there somewhere. It works especially well in Punk as well, and especially Doom Metal. Anything that primarily uses Power Chords can utilize the Harmonic Minor. But we also have one more part of the Minor Scale when it comes to theory for guitarists. And this one is used a whole lot as well!

Music Theory For Guitarists: Melodic Minor

I feel like the Melodic Minor Scale gets a bad reputation because it is often called “Jazz Minor”. To be perfectly fair, it is used a lot in Jazz and Bebop, but it can be used in a bunch of creative ways outside of just Jazz. If you are familiar, and think Melodic Minor is just for Jazz guitarists, then maybe check out The Beatles. Songs like “Yesterday” are a perfect example of the use Harmonic Minor.

But being honest, the Melodic Minor is rarely used just by itself. It is more meant to be used in conjunction with other scales and modes. Play the scale by itself on your guitar in ascending and descending patterns. It definitely sounds…odd by itself right? That’s because Melodic Minor is meant to fill in the gaps left by the other two Minor Scales.

So what are we changing around this time? Well we are keeping the change that we discussed above, by removing the Flat Seventh and replacing it with a Major Seventh. But we are also taking another Interval Number and changing it for Melodic Minor. This time, we are trading the Flat Sixth for a Major Sixth. Try doing it on your own, and see what you come up with.

theory for guitarists
Melodic Minor In C

Now you would think that this changes the whole scale right? I mean, is this even close to being Minor anymore? It is, because of a very important Interval relationship. That Flat Third is still sitting there in the scale, and adding that to the Root and Fifth retains the Minor “sound”. Try out all three of the Minor Scales right now on your guitar, and I think you will see what I mean.

The Flat Third carries the Minor sound for the rest of the scale. Remove that Flat Third, and you are right back to the Major Scale in some capacity. Melodic Minor can be used in melodies for songs, especially on piano. Melodic Minor is not as often used in popular music, and is usually heard in Classical and Jazz. So why is it one of the MAIN Minor Scales if it is so rarely used?

The Harmonic Minor leaves a pretty large gap in notes when descending down the scale when you’re writing melodies, so the Melodic Minor was created to fill in the gaps that Harmonic leaves for some melodies. If that sounds a little confusing, don’t worry, you’re not alone. The greatest example would be “Greensleeves”, and really a ton of Bach’s compositions. Try to pay attention to the descending notes of the melody of those songs.

Melodic Minor is not as dark, or sad as the other two Minor Scales. But it does work in an almost “whimsical” way, and the best example of that I can think of is “Carol Of The Bells”. I am sure you have heard that a million times, but you never really paid attention to the “almost sad” character of that song. This is the Melodic Minor Scale in great display, and another reason that it is so rare, yet used a lot. If that makes sense…

Music Theory For Guitarists: You Have A Lot Of Tools Now!

theory for guitarists

The Minor Scale in all three forms is something you hear all the time, and it is easy to tell the difference between the Major and Minor Scales. There is a lot you can do with just these two scale types, and if you write your own music then these are essential to understand. Writing an epic guitar solo relies entirely on your knowledge of scales and modes, not just “getting lucky” like you may do with chord changes.

If you are improvising a guitar solo for example, knowing all three patterns of the Minor Scale is going to give you a wealth of options. If you hear a weird chord like a Dm7b5 ( D Minor 7, Flat 5), you will know to use the Melodic Minor once you get your ear trained to the sound of each scale. Music theory for guitarists can be a lifetime of experimenting and learning. I have spent 20 years, and I am still learning and taking classes!

That’s right, I have been at it for 20 years at an academic level, and I still take lessons several times a week. I’m lucky to have perfect pitch, and I still struggle with the advanced concepts of music. But every little bit that you learn, is a new tool that you can store away to use. I know a lot, but I am always learning something new. That’s what makes guitar so fun to me!

If you checked out our article on Music Theory For Guitarists, and also read about the Major Scale, you have a lot of usable knowledge from just three articles! Combine this with the trick we showed you to learn the notes of the fretboard, and you have a whole arsenal of knowledge that you can weaponize in your own songwriting. Picture this as a toolbox, and each of these things are a different tool for a different job. Your toolbox is definitely more versatile now!

Christoper Horton

Christopher has been playing guitar and piano for 27 years. He has been active in the professional music industry for over two decades. He has toured for years with several bands and music projects. He worked in LA as a studio musician and engineer working with bands like IAMSOUND, Baroness, Kylesa, Black Tusk, Reflux, and Tripping Daisy. In between giving private lessons, he is recording a solo album for 2022-2023. Christopher plays Schecter guitars, BOSS amplifiers, and uses STL Tones in the studio.

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