What Does ‘In The Key Of’ Mean? A Helpful Beginner’s Guide
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The phrase ‘in the key of’ is something that most people have likely heard at some point whether they’re a musician or not. In the key of C or in the key of E minor for example. When I start with a new beginner student, they’re quite often unsure though what that really means. In fact, a subscriber to my YouTube channel left a comment recently saying exactly that.
So what does in the key of mean? ‘In the key of’ means that the notes from a particular key or scale are the basis for the music. There are 2 parts to the name, the root note of the scale and then the type of scale which begins from that note, major or minor. For example, in the key of C major means you are using the C major scale.
There’s a few more important things you should know with this concept though to understand it fully and lots of other follow up questions students will often have. Learning more about what it really means to be in a key will give you a much better understanding of music and a solid grounding from which to learn your instrument more effectively.
What ‘In The Key Of’ Really Means
When we use this phrase, we’re referring to either a major key or a minor key. A piece of music in a major key means that it uses the notes from the major scale pattern as the backbone to create the music, whilst something in a minor key uses the minor scale pattern. Major and minor scales are the 2 most common you will encounter. To understand keys, you must understand scales.
A great way to think about what a scale actually is, is as a collection of notes that you can use to create music with. An organised group that work well and have a particular sound when used together. It’s almost like a colour palette you could paint a picture with. A major scale or key is often thought of as a bright, happy sound in contrast to minor which has a darker, sadder bent to it. Each type is a specific pattern which can be created starting from any note.
As there are 12 different notes on the piano, there are 12 different places you could start either type of scale from, therefore we can say there are 12 major keys and 12 minor keys. C major or C minor, D major or D minor, Ab major or Ab minor and so on. Technically, there are actually more than 12 of each because some notes can have alternate names. We’ll touch on that at the end but it’s best to keep things simple for now.
Using all 12 notes with no direction can sound chaotic so major and minor scales only use 7 each out of those 12. Assuming they start from the same note e.g C major and C minor, they are not the same 7 though and each one has a specific pattern or spacing between the notes that gives it that signature sound.
If you were to play ‘in the key of’ G minor for example, unless you specifically meant to go outside, you would be locked into the G minor scale going up and down the keyboard or playing patterns, chords and melodies only using those notes, ignoring the rest.
Getting to grips with this idea, learning your scales and remembering to think about it as you’re playing, can really help keep track of what and where things are happing on your instrument. This helps you to better hear and understand how the music is working, which notes to play when reading or playing by ear which in the long run will help you speak the language of music more fluently and become a better musician.
The Root And The Tonal Centre Of The Key
This is a very important concept when understanding keys.The note that the scale starts from is called the ‘root’. Like the root of a tree, that’s where everything begins. You may hear the term ‘tonic’ as well and this note is very important. It acts as the tonal centre of the music and you really must keep this note in mind as the grounding for the key.
By tonal centre, I really mean about how this note sounds in relation to the rest. The root sounds like ‘home’. If you’re in the key of C major, and a melody you play finishes on the note C, it will sound complete, at rest and resolved. Even if you just play up or down the scale on your piano and end on the root, it will sound finished. If, however, you played a melody that ended up on the 2nd note of the scale, for example, it will now sound incomplete, not resolved and like it’s leading our ears on to something else.
In a major key, playing a major chord starting from the first note of the scale (Chord I) will also sound resolved and this is typically (not always) how a piece of music may end. The same is true for a minor chord built from the first note of the scale in a minor key.
In my video on being in a key, you can hear these ideas for yourself.
You Can Still Use Notes ‘Out Of The Key’
The notes that are inside the key are often the main focal point of the music, but there is no rule saying that you can ONLY use those notes. In fact, it would get boring if composers and songwriters only ever stuck to that when there are many other creative musical possibilities available. Without getting technical or theoretical, I want to touch upon 3 common ways in which music may ‘go outside’ of the main key that it’s in.
Passing notes and ornaments
A very common thing to do in all styles of music from classical to jazz and everything in between, is to embellish melodies or passages by using notes in between the scale tones. You can do things like use an outside note to pass between 2 scale tones or perhaps just lead to a scale tone from an outside note around it. You can create all kinds of patterns too, the possibilities are endless.
This can add some extra colour or flavour to the sound, add some interest and create some tension and release. Tension on the outside note and release when we get back to the scale tone. The use of passing tones is heavily prevalent in jazz music but a famous example from the classical world you will be familiar with is the first 2 notes of Fur Elise, which go back and forth between E and D#. The D# is not in the key (A minor)
If it sounds good, you can sometimes also put more focus on the tense sounding notes for effect. This is actually one of the musical elements that make the blues sound the way it does. These are sometimes called ‘blue notes’. Certain styles have certain ways of doing things particular to that style to make it sound authentic, but the only real important rule is, if it sounds good, it’s good!
Briefly Changing The Harmony
When you stick inside a key, that’s called DIATONIC and if you play something outside the key, it’s called NON DIATONIC. A diatonic chord therefore only uses notes from the key. It’s pretty common to see chord progressions using non diatonic chords in order to create more harmonic interest and to play with different colour palettes other than just those afforded by the key itself. This could be a chord beginning from a note outside the key or just a chord beginning from a scale tone which includes outside notes.
When this happens briefly, it’s often simplest to think of it as just changing a chord from what would have naturally have in the key to create something else. Or, for example, starting a chord from the flat 7 when your’e really in a major key. (The flat 7 is just an interval name that is an outside note to a major key, don’t panic if you haven’t learnt intervals yet!)
Sometimes you can get more theoretical and talk about borrowing chords from other keys but I find it’s usually clearest not to if it’s only very brief.
Changing keys
Sometimes a piece of music may completely change key, shifting the tonal centre somewhere else. This may happen for a section and then return to the original key, stay in the new key to the end or even change between multiple keys, multiple times.
There are many ways this can be done but this post isn’t about getting into the theory of how. I will just mention one common way that you will likely have heard, even if you wen’t aware it was a key change. A lot of pop songs like ‘Man in the mirror’ by Michael Jackson will use a key change towards the end to ramp up the energy. It usually just shifts up either a half step or a whole step. ‘Love on top’ by Beyonce is another prime example of this and is famous for doing it multiple times!
Key Signatures
So now we understand what being in the key of something means, we have then have to learn about key signatures.
So what is a key signature in piano? A key signature is a sign used at the start of a piece of sheet music that tells us what key to play in or what scale you are need to use. It does this by showing how many and exactly which notes you need to play as flat or sharp. Each one could be a major key or it’s relative minor.
Then when the notes go up or down on the stave, they go up and down locking inside that scale. Because each key signature could represent a major key or it’s relative minor, that means that for every major scale, there’s a minor scale that contains the same sequence of notes, but instead they just begin somewhere else. There is a new root or a new tonal centre. I have a short but in depth video up on the piano from scratch YouTube channel explaining very clearly below. It’s really useful subject to get to grips with!
You can’t tell just by looking at the key signature alone whether the key is major or minor, there’s not enough information. You need to either play the music to hear the tonal centre or sometimes you can read the notes and infer which it is. It’s often either one or the other but occasionally it may fluctuate at different points of the music and it’s sometimes even a bit ambiguous as to where most sounds like ‘home’. Either way, you have all the information you need to play the correct notes.
What About The Other Types Of Minor Scales?
You may be aware that there are a few variations of the minor scale pattern that are commonly used that chop and change throughout a single piece of music. Technically, these alterations mean we are going outside the key and to indicate them on sheet music, we still use the regular key signature, but add in accidentals (extra sharps, flats or naturals). We do, however, often just speak of them as being in a minor key still as it is such common place to use the harmonic or melodic minor.
If you’re not sure what I mean by these other types of minor scale, I recommend watching this video below which will explaining everything you need to know!
Minor scales PDF Worksheet
I also have a comprehensive PDF worksheet available to download. It’s a clear, handy reference for everything you need to know about minor scales, how to find them easily, clear graphics, finger numbers and notation. You can take a look at that here.
When People Don’t Specify A Major Or Minor Key
Sometimes people might just say ‘in the key of D’ or ‘in the key of E’ without saying major or minor afterwards. This happens with chords too for example and what is USUALLY the case with both, is that people mean major. Sometimes we’re just lazy! But major is commonly the default unless specified otherwise. Musicians can often assume other musicians just know what they mean but if you’re unsure, always ask!
It may also be the case that they are referring to something else, a different kind of scale perhaps or even a chord a just a particular melody. There’s always 12 positions or keys you can play anything in so sometimes people use the phrase without the specific attachment to major or minor.
Technically, There’s More Than 12 Of Each
Because there’s 12 notes on the piano, it’s reasonable to say that there is 12 major keys and 12 minors, totalling 24. Practically speaking, that is true but there’s a few keys that can have more than one name, or spelling of the notes. These are called ‘enharmonic equivalents’. Gb major could be F# major, Db major could also be called C# major and B major could be Cb major. That’s 3 extra, then each of those has a relative minor giving us 6 extra keys, now totalling 30 possible keys!
I’ll be honest though, I really don’t like this approach and think it’s far clearer to just think of 24 plus some alternate spellings. You could say 24 keys, but 30 key signatures. For readers, the other key signatures will be very different to read so need practice! Music theory is a means to an end, to help you understand music in a way that helps you speak the language and improve, so finding the clearest ways to understand concepts is often the best approach.
