If you have explored any music theory concepts before, it is likely that you have come across something called the “harmonic field”. This is what we call the set of chords that come from harmonizing each note of the scale of a key.
For instance, if you want to know the chords that fit in the key of G Major, your starting point is the G Major scale.
Harmonizing each degree of the scale is done by stacking thirds on top of each note until you have triads (three note chords) on every degree (root note, third and fifth).
If this all seems overly complicated for you at this stage, that’s understandable, but the whole concept is actually very simple once you comprehend and memorize a few key details about the harmonic field.
First, let’s go straight to the point and go over the chords that exist in the key of G Major, and then let’s talk about the theory behind them, and check a few examples of chord progressions using these chords.
Chords that belong to the key of G Major
How to figure out what chords fit into a certain key
Now that you know which chords exist in the key of G Major, let’s talk about the theory behind that process, so that you can apply it to other keys, as they show up in real life scenarios. The chords change, but the logic remains the same!
The major scale that corresponds to the key you’re working with is going to be your starting point.
In this case, we will be working with the G Major scale.
G Major only has one accidental, which is F#.
This gives us the following scale:
- G, A, B, C, D, E, F#.
The first step is to write these notes on a staff.
Afterwards, we will need to harmonize them by stacking two thirds on top of each degree (note) of the scale.
You will end up with a triad (three note chord, comprised of root, third and fifth) on each degree.
Pay attention to the accidentals of the key you’re working with, and use them when placing that note on the staff. With G Major, you only need to take that F# into account, all other notes are natural.
By the end of the process, you should have something that looks like this:
While it is great to have the ability to quickly put something like this together and explain the theory behind it, it is also tremendously useful to know a few tips and tricks that allow you to figure out the most important parts of a concept and apply them on the spot.
For the harmonic field, there are a few handy things to take into account in that sense.
Starting with a pattern that is visible on every key, this is what you should start by memorizing as soon as possible:
- Degrees I, IV and V are MAJOR (root, major 3rd, perfect 5th)
- Degrees ii, iii and vi are MINOR (root, minor 3rd, perfect 5th)
- Degree vii is DIMINISHED (root, minor third, diminished 5th)
Memorizing the quality of each degree of the harmonic field is completely essential if you want to apply this concept fast, without having to think about something such as the staff shown above.
These degrees always have the same quality (major, minor or diminished), regardless of the key you’re in, so it definitely pays off to memorize this! You will most certainly benefit from that many time throughout your life!
The next detail that you should always take into account are the sharps and flats of the key you’re using. If you forget to sharpen or flatten a certain note, then your chords and harmonic field won’t be right!
Use the circle of fifths to quickly find the accidentals of each key (full circle of fifths guide here if you’re not familiar).
Another useful tip that will help you avoid making mistakes is remembering that major keys have a semitone interval between degrees iii – IV and vii – I.
In G Major, that is visible between B minor – C Major, and F# diminished – G Major.
If on the other hand you’re working with a minor key, these semitone intervals will appear between degrees ii – iii and V – vii.
The moment these things are clear to you, it will be very unlikely for you to make a mistake when building the harmonic field of any key. It will be quite intuitive, and by repeating this frequently, you will quickly start memorizing some of the chords of each key.
This doesn’t mean that the seven chords you obtain are your only options.
There are more chords that work on their corresponding keys, but they come from other concepts such as modal interchange.
Given the fact that most songs are based on chord progressions that are quite common and similar, knowing and understanding this harmonic concept is crucial if you want to develop your skills as a musician and as a composer!
The next section will give you some examples of popular chord progressions in G Major. Try them out in a new composition, and try to transpose them to other keys as well!
Popular chord progressions in the key of C Major
|Progression(Degrees)||Chords in the key of G Major|
ii – V – I
Am – D – G
I – vi – ii – V
G – Em – Am – D
ii – V – vi
Am – G – Em
I – IV – I – V
G – C – G – D
I – vi – IV – V
G – Em – C – D
By now you have probably realized that investing enough time to fully understand and master the concepts behind the harmonic field is more than worth it.
Doing so will make you more complete and versatile as a musician, regardless of your instrument and genre.
Always remember to check things such as a key’s accidentals, which chords are major, minor and diminished, and the progressions that work best depending on what you’re going for.
Once you become more experienced, chord progressions will become much clearer to you, not only when writing, but also when trying to figure out songs by ear!