A diatonic chord is a chord that naturally fits within a key.
In music we use Roman numerals to label each note from 1-7 (as there are only 7 notes per key). Let’s give you an example in C Major.
C Major Consists of the following notes:
To label our notes, we start with the tonic (In this case that is a C) and we would count our way up the scale as though you were going from left to right on a piano.
Your order should look as follows:
Now we know the notes within the scale as well as the intervals between them! All we need to do now is add in the characteristics of each diatonic chord. Have a look at the major sequence below:
Maj is an abbreviation for Major.
min is an abbreviation for minor.
Dim is an abbreviation for Diminished.
Applying these to the diatonic chord which rests within the same numeral value will give it the characteristic it needs to blend perfectly within your key.
There are many different options to go down when playing/creating chord progressions so we will only be giving one quick example to guide you on building your own. Let’s use a simple I-IV-V Progression. If you look at the tables above you will see that within these placements you have:
C Major – F Major – G Major
Double check to make sure you understand before moving on.
Next we are going to do the same I-IV-V progression but using diatonic 7th chords. Look at the values below:
Dom7 is an abbreviation of a Dominant 7th, often noted as just a 7th chord.
min7♭5 is an abbreviation for a half diminished chord.
Our I-IV-V sequence using the diatonic 7th formula would be:
C Major 7 – F Major 7 – G Dominant 7
Below is your other formulas to build your diatonic chord sequences in different scales and keys.
Harmonic minor 7th:
Melodic minor 7th:
Just remember to start by ordering the notes of your key.
Then apply the scale formula.
Then pick a chord progression to test using these chords.