Music Theory Tree

What actually ARE intervals?

An interval is commonly described as, “the distance between two notes.” Another, more precise definition might be something like, “the difference in fundamental frequency between two pitches, in accordance with a given tuning system.”

As we’ve looked at in previous parts of this series, a set of pitch classes may be mapped to numbers called scale degrees, based on their positions relative to a given pitch class. In the diagram, we once again see the pitch classes of the C Major Scale, mapped to the scale degree numbers 1 to 7.

A common mistake is that people sometimes refer to scale degrees as intervals. They are not the same thing. They can’t be. Why? Because the distance between two pitches can’t be the same as a pitch. Scale degrees are mapped to pitches, but an interval is the distance between them.

However, it’s understandable why one might make this mistake. If we name a pitch by its scale degree, an interval is implied. If we say that the pitch D3 is scale degree 2, then the pitch C3 must be scale degree 1. The interval that separates them is called a second. Specifically, it’s a major second, also called a whole step.

In the diagrams, there are “major intervals” and “perfect intervals.” We’ll explore what these distinctions mean, in due time.

Finally, notice that there are two C’s in this diagram. The latter of the two C’s is called scale degree 8. Given this, we must assume that the second C is of an octave register one greater than the first. The first C, corresponding to scale degree 1, could be the pitch C1. This would make the latter, C2. The first could be C3, and the latter, C4.

We haven’t specifically shown which exact pitches these pitch classes correspond to, but it doesn’t matter, due to the Octave Equivalence Relation (aka Pitch Class Equivalence Relation), which I discuss at length in my first essay about the Chromatic Scale.

Notice that the circle diagram only shows C once. This is because we consider all C’s equivalent under the Pitch Class Equivalence Relation, but not necessarily equal. Two C’s might be identical, but they may also be different. This is the distinction between equivalence and equality. For clarity, I recommend reading the essay I mentioned. If you have questions, as always, please ask.

Find the link to that essay below. It’s about 3700 words long. It took me years to write. It might take you 15-20 minutes to read, if you’re fluent in English.

https://www.facebook.com/share/p/1AFijU4ETa/

In the next part of this series, we will look at “minor intervals”. They may not be what you assume.

INTRODUCING THE MTT TORUS OF FIFTHS

And now for something… completely different. Or… perhaps, seemingly so.

This is my best attempt so far to distill down as much relevant music theory as possible, into the simplest format—a grid system. It may not be as pretty as a Music Theory Tree, but it has the potential to help music theory click for you. I've personally found it very useful, and so have students of mine.

What does this chart show? Let’s break it down, part by part.

THE CIRCLE OF FIFTHS/FOURTHS

First of all, the contents in this chart have been taught for hundreds if not thousands of years, in one form or another. The MTT Torus of Fifths is simply a reimagining of what may be the most well-known and widely-used diagrams in all of Western music theory–the legendary Circle of Fifths (sometimes called the Circle of Fourths).

If you’ve studied the Circle of Fifths, this alternate configuration may be immediately useful and intuitive to you. It reveals things about key structures that aren’t immediately apparent from looking at the Circle of Fifths, because it takes what’s implicit in the Circle of Fifths, and makes it explicit. It’s like opening the book instead of reading the cover.

THE COLUMNS

The grid is laid out such that all like-pitch-classes (which you may know as notes), share a column. There are 12 columns, one for each pitch class. All ‘C’s’ are in the same column, for example. B♯ is enharmonically equivalent to C, so it shares a column. Enharmonic equivalence refers to musical elements that sound the same, but are written differently, based on context. For more information on pitch classes, I recommend my essay on the Chromatic Scale, found here (INSERT)

THE ROWS

The rows are diatonic systems, commonly called “musical keys”. There are major keys and minor keys. In total, there are 30 keys in Western tonal harmony–15 major keys, and their 15 relative minor keys. Some might argue that there are only 12 or 24 keys, and in a sense there are, because some keys are enharmonically equivalent to others. These are keys whose scales sound the same when played, but are written differently. They contain all of the same pitch classes. For example; C Major and B♯ Major are enharmonically equivalent keys. To clarify the argument, one might say that there are 12 or 24 “playable keys” and 15 or 30 “common theoretical keys”. Though one can imagine more keys, the rules of key signatures dictate otherwise. More on this topic another time.

This chart is meant to help teach music theory, so it shows all common theoretical keys. If you’re curious why one might choose to write in a given key or its enharmonic equivalent, follow along for future posts. It’s quite a fascinating space of ideas, and it’s not as arbitrary as one might first think.

THE LEFT LEGEND

The legend on the far left shows relative major and minor pairings. The relative minor of C Major is A Minor, for example. It also shows the number of pitch classes with sharps or flats in that row.

SCALE DEGREES

The small numbers above and below the pitch classes are the scale degrees of the major and minor scales, respectively. So, ‘C’ in the key of C Major has a ‘1’ above it, because it’s the first degree of the C Major Scale. It has a ‘♭3’ below it, because it corresponds to scale degree flat-3 in C Major's relative minor scale, A Minor. Conversely, ‘A’ has a ‘6’ above it, because it corresponds to scale degree 6 in the C Major Scale. However, A is scale degree 1 in the A Minor Scale, so it has a 1 below it.

ORGANIZING THE ROWS

Without getting too deeply into the theory in this post, it suffices to say that the rows are arranged such that their first scale degrees are perfect fifth intervals apart. This is the interval that spans between any given scale degree 1, and its scale degree 5.

So, the key of C Major (or C Major Scale) occupies the middle row. Scale degree 5 of ‘C’ is ‘G’. Therefore, the key of G Major occupies the row below the key of C Major.

Scale degree 5 of ‘F’ is ‘C’, so the key of C Major is found in the row just below the key of F Major.

THE COLOURS OF TRIADS

Each of the pitch classes that have pink backgrounds are the roots of major triads in that row. Notice that ‘C’ in the C Major row has pink behind it. This is because the triad whose root is ‘C’ in the key of C Major is the C Major Triad.

Those with powder blue behind them are the roots of minor triads, such as the A Minor Triad in the key of C Major.

The remaining pitch classes with light purple backgrounds are the roots of diminished triads. In the key of C Major, it's only the B Diminished Triad.

MOVING BETWEEN KEYS

If you’re first starting to study key structures and signatures, the following is a simple way to make sense of the pattern (which may seem arbitrary, at first).

Beginning from the C Major Scale row, notice that the number of sharps increases by one every time we move down one row in the torus. The number of flats increases by one every time we move up one row in the torus.

Why does this happen?

One short answer is that major scales are imbalanced, asymmetrical, and contain a dissonant interval called a tritone. Every time we move from one row to another row, we’re displacing the tritone to a new location. The dissonance and location of the tritone plays a crucial role in dictating where the most consonant tone in the scale is. This most consonant tone in a major key is called the Tonic, or scale degree 1 in its major scale.

The tritone in the C Major Scale spans between ‘F’ and ‘B’. This is a crucially important detail. There's a lot to unpack with this, but for now, just remember this as a brute fact.

The basic instructions for how to displace the tritone follow. Don’t be afraid to ask for help if you would like assistance with understanding this. It’s a bit complex, but learnable.

MOVING TO THE KEY BELOW - ADDING SHARPS

To move to the key below a given key, we find scale degree 4 in our starting major scale, and we sharpen its corresponding pitch class. For example, scale degree 4 in the C Major Scale is ‘F’. We then sharpen ‘F’ to become ‘F♯’. The letter previously attributed to scale degree 4 of the C Major has altered to become scale degree 7 of the G Major Scale. The letter ‘F’ comes along for the ride, but the pitch is now a semitone higher. ‘F♯’ is the “Leading Tone” in the key of G Major, or scale degree 7 in the G Major Scale. Its triad is a diminished triad, which includes that dissonant tritone I mentioned before. The tritone in the G Major Scale spans between ‘F♯’ and ‘C’. So, we’ve successfully displaced the tritone that previously spanned from ‘F’ to ’B’.

I won’t dig too much more into detail about the relevance of the tritone in major scales in this post, because videos with audio examples will do a much better job explaining this. If you want to learn more about the theoretical side of the tritone interval, I have an in-depth video on my page where I teach you how to grow a C Major Music Theory Tree from scratch. I discuss the construction of a B Diminished Triad in that video. There are accompanying exercise sheets for you to download if you like.

MOVING TO THE KEY ABOVE - ADDING FLATS

Let’s finish this short lesson by learning how to move up a row. To do so, we find degree 7 in the major scale and flatten it. In C Major Scale, scale degree 7 is ‘B’. So, we flatten ‘B’ to ‘B♭’. ‘B♭’ is scale degree 4 in the F Major Scale. So, the letter ‘B’, previously attributed to scale degree 7 of ‘C’, has been flattened a semitone to become ‘B♭’, and is now scale degree 4 of ‘F’. What happened to the tritone between ‘F’ and ‘B’ in the C Major Scale? It has displaced to become the the interval between ‘E’, the Leading Tone of ‘F’, and ‘B♭’. Mission accomplished.

CONCLUSION (FOR NOW)

Through repeating these processes, sharpening scale degree 4, and flattening scale degree 7, we can construct every major scale in the torus. This usually takes practice and repetition to make sense of. If you don’t understand the first time, don’t feel alone or discouraged. Read this post multiple times carefully, if necessary. Look closely at the MTT Torus of Fifths and diagrams of the Circle of Fifths. Search for instructional videos online about “changing keys using the Circle of Fifths”, and read through Wikipedia, and other articles. If you want to get these concepts totally down, please get the Music Theory Tree Exercises. They are specifically crafted to help you memorize these patterns.

If you’re curious and would like to learn more (super relatable), follow me. I’ve been studying music theory for a long time, and I have A LOT more to share with you. I’m a person who genuinely wants to help you.

Let’s reimagine music theory.

Be well,

Steve

The C Major Scale: All Natural Pitch Classes From ‘C’ (The Most Important Scale in Western Music Theory, by Far).

Continuing on from my essay about the A Natural Minor Scale (find it on my page), this is the second post in a series, showcasing excerpts from my upcoming eBook, tentatively titled, "Music Theory Tree: An Introduction to Visualizing Music Theory". Please note that this post has been reformatted for social media, and doesn’t perfectly reflect the text in the eBook. I’ve added some bonus parts here, and some of the language has been changed because the eBook contains a lot of images which change the flow of ideas.

We now find ourselves presented with the insurmountable task of expressing the significance of the most essential scale in Western music theory: the C Major Scale. Not only have thousands if not millions of books been written with their central focus around this scale, but it’s not inaccurate to say that the subject of Western music theory itself is largely based on the unique characteristics of this scale. When talking about notes, which are, in a sense, the building blocks of music—the labels attributed to the C Major Scale provide their foundations. From pitch classes, intervals, scales & scale degrees, to chords, modes, and musical keys, the C Major Scale has maintained its primacy in the field for hundreds of years, and there haven’t been any close contenders to dethrone it. It has been the undisputed champion of Western music theory by a long shot since well before you or I were born.

Why? Well, that’s an enormous can of worms, because the historical development of this subject is long and full of weird twists, but let’s start with some basic facts. We’ll leave the history lessons out of this for now. This is an introductory lesson about what this scale is, what it’s made of, and why it’s so important. The question about “How does one make use of this scale?” is another related giant can o’ worms, which we’ll be exploring in supporting essays and video demonstrations. We’re going to keep it purely theoretical here, for the time being. Further, the physics that inform this scale will also be left to other discussions. Those things are best demonstrated aurally.

The #1 most important thing about the C Major Scale is the following:

The C Major Scale is the only heptatonic scale whose pitch classes and scale degrees are all naturals.

There are no other scales which qualify in these three ways.

Let’s dive into each of these three criteria.

Claim 1: “It’s a heptatonic scale.”
This means it contains seven pitch classes. Hepta refers to the number seven, and tonic refers to tones (which are labeled based on their frequency, organized by pitch classes). It’s possible to construct a large set of many distinct heptatonic scales using the pitch classes of 12-Tone Equal Temperament; the A Minor Scale being another example.

However, none of them will satisfy the other two criteria mentioned.

Claim 2: “Its pitch classes are all naturals.”

The pitch classes in the C Major Scale are (C, D, E, F, G, A, B). We’ve already observed that the A Minor Scale also contains this set of all seven natural pitch classes. However, it does not contain all natural scale degrees. The reason for this comes down to the difference between the sequence of intervals that make up a major scale, and those of a minor scale.

Claim 3: “Its scale degrees are all naturals.”

It is conventional to number the pitch classes of a scale in alphabetical order from 1 to 7. These numbers are called scale degrees.

Recall that the sequence of intervals that define a minor scale is: (W, H, W, W, H, W, W). The degrees of a minor scale are (1, 2, b3, 4, 5, b6, b7). Notice the three flats. Why are they there? Because scale degrees are derived from the intervals of a major scale, not from those of a minor scale.

The scale degrees of any major scale are simply (1, 2, 3, 4, 5, 6, 7). In other words, when we say “scale degrees” we technically mean “scale degrees relative to those of a given parallel major scale”. Parallel scales are those whose first scale degree corresponds to the same pitch class. For example: the A Minor Scale and the A Major Scale are parallel scales. They both begin with ‘A’, and therefore, scale degree 1 for both scales is ‘A’.

The interval formula for all major scales is (W, W, H, W, W, W, H). This is the most important ordered set of intervals in Western harmony. When we repeat this ordered set, we get a periodic sequence that goes on forever. (More on that later). If we apply this ordered set of intervals to the Chromatic Scale, beginning from ‘C’, we get the ordered set of pitch classes (C, D, E, F, G, A, B). These correspond to the numbers (1, 2, 3, 4, 5, 6, 7), respectively. Notice there are no sharps or flats in either ordered set. There are no sharps or flats in the ordered set of pitch classes, nor in the ordered set of scale degrees. Both ordered sets only contain all naturals.

Now, I am not about to embark on a rigorous proof here, demonstrating that the C Major Scale is the only scale that satisfies all three of these criteria. It’s not my mission to convince you of that today. If you’re not wanting to take my word for it, I challenge you to find another scale that does, or prove me right or wrong mathematically. It will surely serve as a good learning experience for everyone. What matters most for our purposes is that given the C Major Scale is the only scale of all natural pitch classes and scale degrees, it is the simplest to work with. That’s why it’s important. That’s why it’s so widely used.

All other scales in 12-TET may be defined based on their intervals, pitch classes and scale degrees, relative to those found in the C Major Scale.

One might ask a totally well-reasoned question…

Why is this the case? Why would the natural pitch classes correspond to the natural scale degrees in the major scale starting with ‘C’ and not ‘A’? It’s strange, I know. Once again, it’s a long story, involving the historical development of music theory, the physics of sound, and the way human beings experience certain kinds of sounds—specifically, periodic sounds. More on that another time.

To be a bit more explicit about the relationships between pitch classes, intervals, and scale degrees, let’s look at a couple examples.

Let’s compare the C Major Scale to its parallel minor scale, the C Minor Scale. It may be defined as the ordered set of pitch classes (C, D, Eb, F, G, Ab, Bb). Its intervals are (W, H, W, W, H, W, W) because that’s the minor scale interval formula. We’ve just applied it to ‘C’ instead of ‘A’. When we apply this formula to the Chromatic Scale, beginning from C, we get the pitch classes listed. Its scale degrees are (1, 2, b3, 4, 5, b6, b7), because those are the scale degrees of a minor scale. Notice that the flats attached to the pitch classes align perfectly with the flats attached to the scale degrees. This perfect correspondence between accidentals in pitch classes and scale degrees, only occurs with scales that begin with ‘C’. This further reinforces the unique power of the C Major Scale.

On the other hand, let’s compare the A Minor Scale to its parallel major scale, the A Major Scale. The A Major Scale may be defined as the ordered set of pitch classes (A, B, C #, D, E, F #, G #). It’s a major scale, so we simply applied the major scale interval formula to the Chromatic Scale, beginning from ‘A’, giving us this ordered set. It’s a major scale, so these pitch classes correspond to the scale degrees (1, 2, 3, 4, 5, 6, 7), respectively. Notice that there are sharps accompanying three of the pitch classes, but not the scale degrees. Once again, this is because only scales that begin with ‘C’ will have matching pitch class and scale degree accidentals.

To put a little bow on this analysis, consider the pitch classes and scale degrees of the A Minor Scale, once again. Its pitch classes are defined as the ordered set (A, B, C, D, E, F, G). Its scale degrees are (1, 2, b3, 4, 5, b6, b7). In other words, to get the A Minor Scale, we flatten the pitch classes of the A Major Scale that have sharps attached to them, making them naturals. This is reflected in the scale degrees of the minor scale. As a consequence, we’ve effectively “cancelled out” the sharps in the pitch classes, by flattening them, thereby making them naturals.

To summarize, one might say that the most generalizable and simple interpretation of Western music theory is that it’s all a matter of investigating the distinct correspondence between the pitch classes and scale degrees of the C Major Scale in a multitude of ways.

See you next time! Please share this with people you think will appreciate it!

The A Minor Scale: All Natural Pitch Classes From ‘A’

This will be the first of many posts showing excerpts from my upcoming eBook, tentatively titled: “Music Theory Tree: An Introduction to Visualizing Music Theory”.

The A Minor Scale may also be referred to as the “A Natural Minor Scale”, or even the “A-Natural Natural Minor Scale.” Usually people just use the simple name. The reason the other two names may be used is that there are other kinds of “A’s”, like A-sharp and A-flat, and other kinds of minor scales, like the harmonic minor and melodic minor scales, to name two. One could have an “A-Sharp Harmonic Minor Scale” and if one were discussing it in comparison to the A Minor Scale, more explicit labeling might help the audience keep things straight. Though, most people who routinely speak about such scales don’t require such explicit labeling. Using the word “natural”, meaning “unaltered”, in music theory is generally unnecessary, because it’s implied. This is consistent with typical English language.

In any case, with this formality out of the way, let’s explain what the A Minor Scale is, where it comes from (in brief), and why it’s important. We’ll leave the question of “How does one apply this to composition and analysis?” to later posts with videos so I may demonstrate and we can discuss that directly.

Most simply, it is a scale consisting of seven pitch classes, labeled as the letters A through G. Pitch classes are sets of pitches that are considered equivalent under the Octave Equivalence Relation. For more on that, please visit my essay, “Meet the 12 Pitch Classes of 12-Tone Equal Temperament, aka “The Musical Alphabet”, or “The Chromatic Scale” here: https://www.facebook.com/musictheorytree/posts/1401253997494056 published on my page.

Typically people use the term “note” where I use the term “pitch class”. This is a formality, and these terms may sometimes be considered interchangeable, but technically speaking, in Western music theory, the latter is more precise when discussing the letters A through G, and their altered versions. I try to reserve the term “note” for discussions of musical notation in sheet music. These two spaces are importantly connected, but distinct, in my view. My arguments for this are described in the aforementioned essay. I welcome any edits and criticisms one may have of it.

It is common to teach Western music theory with a piano keyboard, because the pitches of natural classes are produced by striking white keys, and those with sharps or flats, with black keys. This convention is reflected in these diagrams. The naturals are on white backgrounds. The others (not listed here) would be on the black backgrounds. The colour coding of the pitch classes will be discussed in the next post.

If one takes the Chromatic Scale of 12 pitch classes in 12-Tone Equal Temperament, beginning from A, and removes all of those with sharps or flats, one is left with the A Minor Scale. It may be also described as all of the natural pitch classes, beginning and repeating from A, because pitch classes repeat at multiple registers, due to the Octave Equivalence Relation. In short, the Octave Equivalence Relation exists because we hear certain pitches as especially similar to one another; so much so, that they receive the same pitch class symbol. So, a scale may be observed as a linear system or a cyclic system. This combination of being both linear and cyclic makes the A Minor Scale, and all musical scales “Periodic”. Therefore, one can confidently define musical scales as “periodic sequences of pitch classes”.

It is common for music theorists to use little arches to connect two pitch classes together, demonstrating the distance between them. These little arches are called “cycloids”. They resemble the trail of a bouncing ball from one object to the next. These cycloids represent what are called “intervals”, often described as “the distance between two notes” but may be more precisely described as “the difference in frequency between two pitches, in accordance with a given tuning system”.

There are two types of intervals shown here: whole steps (W’s) and half steps (H’s). These may also be referred to as “whole tones/tones” and “semitones”, respectively. I prefer the former, because the word “tone” in music theory is overloaded, and could cause more confusion. They may also be called “Major Seconds” and “Minor Seconds”, respectively. More on this naming convention later.

If we run through the intervals between the natural pitch classes of the A Minor Scale, skipping over those from the Chromatic Scale with sharps or flats, we get the “Minor Scale Interval Formula”: (W, H, W, W, H, W, W). This pattern of intervals may be applied to any pitch class, and a distinct ordered set of pitch classes will emerge. For example, if we apply this intervallic formula to the pitch class C, the resulting scale is (C, D, E♭, F, G, A♭, B♭). This is known as the “C Minor Scale”.

Again, the reason why the A Minor Scale is so important, is that if and only if one begins a minor scale from A, does one get the letters A through G, with no sharps or flats. That makes it especially easy to work with. The A Minor Scale is therefore a member of a distinguished set of seven scales I like to call “The Diatonics of All Natural Pitch Classes (DOANPC’s)”. The A Minor Scale is a super important scale in Western music theory, second only to the next scale we will look at; namely, the C Major Scale.

What does “diatonic” mean? More on that soon, too.

The most important takeaway from this post is that if one wants to learn music theory, one must remember that all pairs of neighbouring natural pitch classes have a pitch class separating them, except for the pairs (B, C) and (E, F).

Please let me know if you have any questions. I am here to help.

Let’s reimagine music theory.

Steve Evans From Winnipeg

Hello, musicians, music students, teachers, & all other friends of music theory!

Let’s begin by pointing out the obvious, shall we? There is a lot going on in this map. Some might say too much, and others, not enough. In fact, the contents shown only account for a tiny fraction of the subject matter in music theory. However, this map is only part of a larger modular system. It may be manipulated to accommodate different goals. Parts may be added or taken away to illuminate diverse subject matter. This one illustration just happens to be an especially important one, and one of my favourites, so I’m sharing it with you.

If you think others might appreciate a look at it, please share it with them. I ask that if you do so, please share this exact, original post instead of downloading and posting the image separately. This will ensure the quality of the image is maintained, and people will know where to go to learn more about it if they have questions.

I’ve discovered through years of research, that the Music Theory Tree System is super versatile and its many uses become intuitive once one receives the right guidance and practices with it. The key to doing any kind of abstract work (like a music theorist does) is to read between the lines; fill in the gaps with knowledge acquired from elsewhere. No well-rounded education is completed by reading a single book, let alone looking at a single picture, so don’t expect to download all of humanity’s wisdom of music by looking at this map. (Though, that would be pretty cool if it miraculously happened, I’m not holding my breath). Could a large set of books and diagrams together contribute to a more well-rounded understanding of a subject? I think we can sensibly agree, yes. Further, repeatedly completing related exercises is sure to help the information stick best.

I figure, instead of attempting to explain all of what’s shown here in a brief post (because that’s impossible, as there is infinitely much that may be said, and infinitely many applications for this), I’d like to open up the floor to you. I will do my best to answer questions, and I humbly welcome any comments and criticisms you may have. I aim to help as many people learn music theory as possible, within my means. These maps are just some of the visual tools I employ as part of that mission. They're not meant to serve as a substitute, but as a companion. Again, parts may be added and taken away, this configuration is being published the way it is to maintain visual continuity across multiple Music Theory Tree Maps.

Please, try not to feel intimidated by this or criticize it immediately. Instead, I Invite you to feel inspired and curious, because you, like myself, may learn a lot from studying in this way, if you want to. It’s simply a matter of dedicating time, practice, and holding a belief in yourself; a belief that you are capable of learning what you set your mind to. Too many people get discouraged when they encounter something new and complex. Remember, this is just a map, after all. It's not intended to tell you where to go or what to do, but rather show you some roads you may choose to follow (or not). It just shows how certain concepts may be understood as connected. One needn’t take every road, but might take some. I encourage you to even make your own roads and map them. Who knows where they might take you?

Music is complex, and music theory, which I understand to be the language used to discuss and describe music, may be equally complex. Some of the complex concepts and relationships in this particular map require a fair bit of prerequisite knowledge to make practical use of. For a more detailed look at the simpler structures that make up this map, please follow my page, where I’ll be sharing supporting materials in the form of essays, video lessons, and other, much simpler maps.

February 23rd, 2025 will mark the beginning of my seventh year working on this project, and the bulk of what I have created to share with you so far will be published this year. I appreciate every one of you who has been supportive of this project and I’m equally appreciative of those who have been stress testing this project through rigorous discussion over the last few months. You all have inspired me, immensely.

Some answers to your many questions are coming. Please continue to ask them. Sometimes, the journey towards learning something new and profound is just a question away.

Let’s reimagine music theory.

Be well,

Steve Evans From Winnipeg
Owner & Founder of Steve Evans Education Studios (SEES) & Music Theory Tree (MTT)