Music Theory

Playing Piano Triads: Music Theory in Action

By Rebecca Carlson

Curious about triads in music? Learn how to play piano triads below

A triad is a set of three notes spaced in thirds and played at the same time. Piano triads are foundational to piano music and playing the piano. They’re simple enough for a beginner to learn and play, but they’re also part of the most advanced piano arrangements of both popular and classical music. Without triads, music as we know it wouldn’t exist!

What are triads in music?

Triads are built by playing every other note of a musical scale. For example, to play a C major triad, you’d start with C, then skip up to E, then skip up again to G. These three notes, C-E-G, form a triad. Triads provide a rich, full sound because the pitches are as close together as they can get while still sounding harmonious to our ears.

Triads form the backbone of accompaniment patterns in Western music. They help define the mood that the music conveys. Different triads can create either a sense of tension or resolution as the music progresses through the piece. 

Keyboard instruments like the piano and organ are especially suited for playing triads. You’ll find them played as blocked triads, which are three notes sounded all at once, or as broken triads, which are three notes played one after the other, as in an arpeggio.

What are the 4 types of triads in music?

There are four types of triads in music. They can be identified by the intervals between each pair of notes. 

Major triad

In a major triad, the lower two notes are separated by a major third and the higher notes are separated by a minor third. In the example we used before, C-E-G, C and E form an interval of a major third, or in other words, they’re four half-steps apart. E and G form an interval of a minor third, or in other words, they’re three half-steps apart.

C major triad on keyboard and staff

 

Minor triad

In a minor triad, the lower two notes are separated by a minor third and the higher notes are separated by a major third. If you take a major triad and lower the middle note by one half step, you’ll have a minor triad. An example of a minor triad is C-Eb-G. The middle note has been changed from E in the major triad to Eb in the minor triad. C and Eb are only three half steps apart, while Eb and G are four half steps apart.

C minor triad on keyboard and staff

Try playing the C major and C minor triads on the piano. Listen to the way the sound changes when the middle note moves one half step. It’s amazing that such a small difference in the notes makes such a big difference in the sound, isn’t it?

When you build triads starting on different notes in a scale, most of the triads will end up being either major or minor triads. For example, in the key of C, the triads built with the lowest note on C, F, and G are major, while the triads built on D, E and A are minor. Next, let’s explore some of the less common triads.

Diminished triad

A diminished triad has minor thirds between both pairs of notes. To play a diminished triad, start with a minor triad and lower the highest note by one half step. For example, C-Eb-Gb is a diminished triad. From C to Eb is three half steps, and from Eb to Gb is another three half steps. A diminished triad has an unsettled sound because the notes are getting closer together and their sounds are starting to overlap. In an ordinary major scale, a diminished triad occurs only once, when a triad is played starting on the seventh tone of the scale. In a natural minor scale, you’ll get a diminished triad when you start on the second tone of the scale.

C diminished triad

 

Augmented triad

An augmented triad has major thirds between both pairs of notes. For example, C-E-G# would be an augmented triad. The notes of major and natural minor scales can’t form augmented triads without using accidentals. Augmented triads have a shimmery, unresolved sound and they’re often used in jazz and other modern music styles.

C augmented triad

 

How do you play piano triads?

The simplest way to play a piano triad with your right hand is to use your thumb, your middle finger, and your pinky finger, in other words 1-3-5. These are the fingers that fall on the notes of a triad when you place your hand on the five notes of any pentascale. 

For the left hand, reverse this pattern. The lowest note of the triad is played with the pinky, the middle note with the middle finger, and the highest note with the thumb. 5-3-1 will be the finger pattern.

Unlike scales, for which we often avoid playing the black keys with the thumb, when the lowest note of a triad is a black note for the right hand or the highest note of a triad is a black note for the left hand, the pianist still plays that note with their thumb. To do this, slide the hand forward, deeper into the keyboard, so your thumb can reach. 

Don’t forget to keep your fingers curved and relaxed and use a flexible wrist and the weight of your arm to sound the notes. It might feel a little strange to play this far forward on the keys, so practice playing piano triads that begin or end with black notes until you’re comfortable with it.

How to use triads in piano playing

Once you’ve learned to play piano triads, you’ll have an amazing tool that you can use to make your piano playing so much easier. You’ll often see triads in music, and when you do, you’ll be able to play them easily and confidently. 

Triads also come in handy when you’re playing music from a lead sheet, which is a kind of sheet music where only the melody and chord symbols are written down. One of the simplest ways to use chord symbols is to play the triad built on the root of the chord, which will be the note whose letter name is the chord symbol. Chord symbols will even tell you if a triad should be major, minor, diminished, or augmented! Check out this post to learn more about reading and playing piano chords.

Enjoy learning and playing piano triads!

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