We’ve learned quite a few chords by now, and you may be wondering exactly what a chord is. Let’s prepare to take a look under the hood (in the next tutorial post).
Most simply, a chord is a group of three (or more) notes of a scale, played simultaneously.
You could really play any notes in a scale simultaneously, but it won’t always sound pleasantly musical (‘consonant’). Sometimes it will sound unpleasantly noisy (‘dissonant’). Both consonance and dissonance can be very useful (e.g. in romantic comedies versus horror movies). Listen to examples of both consonance and dissonance here:
Although there is still some disagreement as to the underlying reasons and mechanisms, humans may have an innate biological preference for consonance over dissonance. The brain of a human newborn can distinguish between consonance and dissonance as early as one day post-partum, and – at least by two-months of age – infants prefer consonant to dissonant music. Additional species (e.g. macaques, and songbirds such as sparrows and starlings) are also able to distinguish consonance from dissonance, although preference is unclear.
Others argue that the consonance/dissonance preference is a product of culture and degree of exposure to consonant music. However, three day-old chickens incubated, hatched, and raised in a controlled, soundproof environment still prefer to spend time near speakers producing consonant, rather than dissonant, music. Even humans with a condition called amusia – the inherited inability to distinguish pitch, sing in tune, recognize melody, and distinguish consonance from dissonance – prefer consonance.
We’ll discuss the physics underlying the phenomena of consonance and dissonance in a future post, but, for now, let’s consider how they come about from a musical perspective.
The pitch distance between any two notes in a scale is called an ‘interval’. There are multiple interval possibilities:
unison – no distance (the same note of the scale, played twice)
second – distance from the 1st to the 2nd note of the scale
third – distance from the 1st to the 3rd note of the scale
fourth – distance from the 1st to the 4th note of the scale
and so on (even beyond an octave).
When using notes from the major scale, you end up with major intervals. For example, a major second contains a whole tone distance, a major third contains two whole tones, and so on.
When using notes from the minor scale, you end up with minor intervals. For example, a minor second contains only a semitone distance, a minor third contains only three semitones, and so on.
Notice that the unison, 4th, 5th, and octave interval distances (0, 5, 7, and 12 semitones, respectively) are always the same, whether you use a major or a minor scale to build them. For this and other (more complicated) reasons, these intervals are referred to as ‘perfect’.
Apart from having a major or a minor quality, interval identity can be altered to produce additional forms:
- augmented, in which the higher-pitched note is one semitone higher than expected (its pitch has been sharpened)
- diminished, in which the higher-pitched note is one semitone lower than expected (its pitch has been flattened).
Each specific type of interval evokes a very distinctive feel. You can listen here:
If you’d like to test your ability to identify intervals, here’s a handy online tool.
That’s it for today. In the next tutorial post, we’ll use this knowledge of intervals to understand how chords are built.
Until then, happy playing!
P.S. Song of the day: Call It Off by Tegan and Sara
If you like Call It Off, please consider helping to support Acoustic Notes by getting it here
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