What are Pentatonic Scales?
In music, a pentatonic scale is a scale that has five notes per octave. This is different from the heptatonic scale like the major and minor scales which have seven notes per octave. The word “pentatonic” comes from the Greek word πέντα (penta) meaning five and τόνος (tonos) meaning tone.
Pentatonic scales are found all over the world and are very old. No one knows for sure how old they are, but they are found in ancient music from many different cultures. This includes Celtic folk music, Hungarian folk music, West African music, African-American spirituals, Gospel music, American blues music, jazz, American country music, and more.
What Makes Pentatonic Scales Special?
There are a few reasons why pentatonic scales are so common and popular across many types of music:
Easy to Play and Sing
Pentatonic scales are relatively easy to play on many instruments, and also easy to sing. This is because there are only five notes to remember per octave. Having fewer notes makes it simpler to improvise and make up melodies on the spot.
Absence of Semitones
The most common pentatonic scales do not contain semitones (half step intervals). Notes that are a semitone apart can sometimes sound tense or create dissonance. So by only using notes that are a whole step apart or more, pentatonic melodies tend to sound pleasant and harmonious.
Hard to Play “Wrong Notes”
In some pentatonic scales, like the major pentatonic, you can play almost any combination of the five notes and they will sound good together. This makes it an appealing scale for people new to an instrument or improvisation. It’s hard to hit a “wrong note.”
Unique Sound
Even though pentatonic scales are common, they still have a unique sound that is distinct from scales with seven notes. The lack of semitones and the wide intervals between some notes gives pentatonic melodies a characteristic sound. Some describe it as sounding open, airy, or hollow. To many, the pentatonic sound is very recognizable.
Formula for Pentatonic Scales
A pentatonic scale can be made by starting with a heptatonic scale and removing two notes. The most common way to do this is to remove the 4th and 7th degrees of the scale.
If we take a major scale and number each degree of the scale, it would look like:
1 – 2 – 3 – 4 – 5 – 6 – 7
If we remove the 4th and 7th notes, the remaining notes become the major pentatonic scale:
1 – 2 – 3 – 5 – 6
And if we renumber those notes in order from 1 to 5, the formula for a major pentatonic scale becomes:
1 – 2 – 3 – 4 – 5
So to make a major pentatonic scale, choose any starting note, then use the intervals:
- whole step
- whole step
- minor third (3 semitones)
- whole step
For example, a C major pentatonic scale would have the notes:
C – D – E – G – A
Major and Minor Pentatonic Scales
Just as there are major scales and minor scales, there are also major pentatonic scales and minor pentatonic scales.
The formula given above, 1 – 2 – 3 – 4 – 5, is for a major pentatonic scale. To make a minor pentatonic scale, start with a natural minor scale and again remove the 4th and 7th degrees.
The formula for a minor pentatonic scale is:
1 – b3 – 4 – 5 – b7
This means a minor pentatonic scale has a minor 3rd (b3), a perfect 4th, a perfect 5th, and a minor 7th (b7).
For example, an A minor pentatonic scale would have the notes:
A – C – D – E – G
Notice that these are the same notes as the C major pentatonic scale. Every major pentatonic scale has a relative minor pentatonic scale that shares the same notes.
Blues Scale
The blues scale is essentially a minor pentatonic scale with one additional note, the b5 (flatted 5th). This note is sometimes called the “blue note.” Adding this one note to the minor pentatonic gives the blues scale its characteristic sound. The formula for a blues scale is:
1 – b3 – 4 – b5 – 5 – b7
An A blues scale would include the notes:
A – C – D – Eb – E – G
Hemitonic and Anhemitonic Pentatonic Scales
Most common pentatonic scales are anhemitonic, meaning they do not contain semitones or half steps between any of the scale degrees. Examples of anhemitonic pentatonic scales include:
- Major Pentatonic (1 – 2 – 3 – 5 – 6)
- Minor Pentatonic (1 – b3 – 4 – 5 – b7)
- Ritusen (1 – 2 – 4 – 5 – b7)
However, there are other types of pentatonic scales that do include half steps. These are called hemitonic pentatonic scales. The blues scale is an example of a hemitonic pentatonic scale because of the half step between the 4 and b5.
Another example of a hemitonic pentatonic scale is the In Sen scale used in traditional Japanese music. It has the following intervals:
1 – b2 – 4 – 5 – b6
While hemitonic pentatonic scales do exist, the vast majority of pentatonic scales used in popular music are anhemitonic.
Examples of Songs Using Pentatonic Scales
Countless popular songs have been composed using only the notes of a pentatonic scale. Here are a few well-known examples:
“My Girl” by The Temptations
This classic song uses an Eb major pentatonic scale. The melody only contains the notes Eb, F, G, Bb, and C.
“Swing Low, Sweet Chariot”
This African-American spiritual song uses notes from the Eb minor pentatonic scale. Spirituals and work songs often used pentatonic melodies that were easy for untrained singers.
“Amazing Grace”
One of the most famous hymns of all time, “Amazing Grace” primarily uses notes from a G major pentatonic scale, with an occasional 4th (C natural).
“Ol’ Man River” from the musical Show Boat
The melody to this song relies heavily on a Bb major pentatonic scale. Like spirituals, pentatonic scales are very common in musical theater.
“Auld Lang Syne”
This Scottish folk song uses a pentatonic scale. Pentatonic melodies are a key part of the folk music traditions of Scotland and Ireland.
“Day Tripper” by The Beatles
The main guitar riff to “Day Tripper” is a great example of a riff based on a pentatonic scale. Pentatonic patterns are very common in rock and blues guitar playing.
Pentatonic scales, while seemingly simple, are an essential building block of melodies across a wide variety of musical genres and traditions worldwide. Understanding their sound and structure provides a foundation for composing, improvising, and appreciating music.
