How to make chords. Intervals and Diatonic Harmony

Fret Works Guitar - Course by Lucas Crossley Guitar
Chord Structure & Diatonic Harmony - How Triads are Built
In this lesson we learn how intervals are used to build major, minor and diminished chords or triads (3 note chords). We learn how chords fit into a specific key and discuss common terminology musicians use to describe chord progressions within a given key.
Triads are 3 note chords made up of intervals that are always a 3rd apart. A chord is any combination of 3 notes played simultaneously regardless of the intervals used in the chord.
Previously, we learned about intervals and what intervals are used to construct the Major scale. If you don’t have a decent grasp on the content of those lessons, please review them before moving on.
As a reminder, Major Triads are made up of the following Intervals; Root Major 3rd & Perfect 5th and minor triads are made up of Root, minor 3rd & Perfect 5th intervals. In most common major and minor chords shapes the Root, 3rd and 5th could appear multiple times in the chord.
Diminished triads are made up of the following intervals; Root minor 3rd and Diminished 5th (flat 5). We won’t be getting in depth with diminished chords at this time so don’t worry too much about them. I just want you to understand their construction.
You can see that the only difference between a Major and minor triad is the 3rd degree. It changes by one semitone. Either a Minor 3rd Interval for the minor triad and a Major 3rd Interval for the Major triad.
Let’s look at the construction of the C Major Scale.
The Major Scale is built on the following MAJOR intervals;
Root, Major 2nd, Major 3rd, Perfect 4th, Perfect 5th, Major 6th, Major 7th, and Octave or Tonic. The notes would be C D E F G A B and then the pattern repeats. Notice that there are no minor intervals in the Major Scale.
You can use this interval pattern to generate any major scale beginning on any Root note you choose. If you chose a new Tonic, say G and used the same interval pattern the notes would be G A B C D E F# and you would have constructed a G Major scale. For now, we’ll focus on the key of C.
To play in the key of C we build chords from each scale degree. The Scale degree is simply the numeric position of the note within the scale. For example C is the 1, D is the 2, E is the 3 and so on. All of the chords in the key of C are built using notes from the C Major Scale.
Experienced musicians often refer to these chords by their numeric position within the scale or their scale degree rather than the actual chord name. These are typically represented with Roman Numerals.
The pattern is ALWAYS Major, minor, minor, Major, Major, minor, Diminished
The 1, 4, 5 chords are always major.
The 2 3 6 chords are always minor and the 7th chord is always diminished.
For example; 1 is C major 2 is D minor 3 is E minor 4 is F Major 5 is G Major 6 is A minor (relative Minor) and 7 is B diminished
You might be asked to play a 1 4 5. In the key of C this would be CM FM and GM. You could be asked to play a 1 6 2 5 which would be a CM Am Dm and GM. It’s not uncommon for a band leader to call out chord changes during a live performance. They will simply hold up the number of fingers to indicate which chord is coming next. So, you can see how this information is important.
All of this is referred to as Diatonic Harmony. All of the chords in the Key of C Major are built using notes from the C Major scale. If written on the musical staff the notes would ascend diagonally by thirds and relate back to the Tonic. Dia for Diagonal and Tonic for the root.
Most modern music is diatonic. Meaning that all the chords used in the song relate back to the tonic.
Let's look at each Triad in the key of C
CM - C E G / Root Major 3rd Perfect 5th
Dm - D F A / Root minor 3rd Perfect 5th
Em - E G B / Root minor 3rd Perfect 5th
FM - F A C / Root Major 3rd Perfect 5th
GM - G B D / Root Major 3rd Perfect 5th
Am - A C E / Root minor 3rd Perfect 5th
Bdim - B D F Root minor 3rd Diminished 5 or flat 5
If you play these in pairs you notice they are stacked 3rd intervals either Major or Minor depending on the position of the chord within the scale.
Each chord in the key has a function. Essentially, the sound of the chord creates tension that is asking to be resolved. Some chords will want to take your ear back to the home or 1 chord and other chords will lead your ear away from it but ultimately regardless of the key you’re in the chords will always have the same function.
Make sure you practice this in all keys and remember the formula is always the same regardless of the key.
The 1, 4, 5 chords are always major.
The 2 3 6 chords are always minor and the 7th chord is always diminished.
©2020 Lucas Crossley Guitar

[@Zack-hn2ui]

Hey buddy !! Havent seen you for a couple of weeks now, hope your fine and having a great summer !! Wish you a great vacation !! Have a good one !!👍🎸

[@LucasCrossleyGuitar]

Thank you Zack! Summer is great! How about you? I apologize for my absence lately. I’ve been super busy but in a good way. Recording and arranging some music for a tune on a friends record. Also, working on a piece for documentary about Blues Music here in Canada. And things here are opening up. My boys are getting back to sports and work has been crazy (again in a good way though). I really appreciate your note. I should probably do a live some evening. Just a hang out where all us guitar enthusiasts can chat about whatever pops up. It was really nice to see your comment this morning. Thanks buddy!! Cheers.