Triads — the four basic chord flavors

What a triad is

A triad is a three-note chord built by stacking two thirds on top of each other. There are exactly four kinds, depending on what kind of thirds you stack.

If “stacking thirds” feels abstract, say it this way first: choose a starting note, skip one scale note to find the 3rd, then skip one more scale note to find the 5th. In C major, start on C, skip D, take E, skip F, take G. That gives C E G.

Visualised as a stack of intervals:

That’s a C major chord. Stack of two thirds. Done.

Hearing the four flavors

• Major = bright, resolved, happy.
• Minor = sad, melancholy.
• Diminished = unstable, tense, “creepy”.
• Augmented = ambiguous, dreamy, suspended.

Play each one on a single string set (root on the 5th string, others on the 4th and 3rd) and listen. The difference between major and minor is one note — the 3rd, moved by one fret. That single note is what makes a chord “happy” or “sad”.

Build a triad from any note

To build a major triad on G:

1. Root = G.
2. Major 3rd above G = B (4 semitones up).
3. Perfect 5th above G = D (7 semitones up).

→ G major = G B D.

Want G minor? Lower the 3rd by a half-step: G B♭ D. Want G diminished? Lower both the 3rd and the 5th: G B♭ D♭. Want G augmented? Raise the 5th: G B D♯.

This is the entire recipe. From now on, you can construct any triad in any key without a chord chart.

Triads on the guitar

The simplest triad shapes are on strings 1-2-3 (the top three strings). Three notes, easy fingerings. Use them for rhythm and chord melody.

For a C major triad on strings 1-2-3:

1:  fret 3  (G)
2:  fret 5  (E)        ← wait, the B string + fret 5 = E
3:  fret 5  (C)        ← G string + fret 5 = C

→ Notes from low to high: C E G = C major. (Fret 5 on the G and B strings, fret 3 on the high E.)

We’ll cover all the triad shapes on every string set in the Chord Library reference.

Try this

Pick any natural note (say, D). Build its major, minor, diminished, and augmented triads from scratch — no charts. Then find each on the fretboard. Play them one after another and listen to the four moods.

This single drill, done with different roots, will give you complete triad fluency in a few weeks.