# 5 Revisiting key concepts

You have now considered the constituent notes of the Western pitch system and how these are represented – on the one hand by the keys of keyboard instruments, and on the other by notes placed on the staff. You have also practised writing and performing notes with the help of staff notation.

The Western pitch system you have been studying, like many others, is made up of a series of discrete notes that are organised into a system. These notes resonate at different frequencies and thus sound distinct from one another.

Some notes within the system have a relationship of similarity rather than difference because they are octaves of one another. Octaves can be understood as higher or lower instances of the same note. This allows you to sing along with notes on a keyboard that are higher or lower than is possible for your actual singing voice (something you were asked to do in some of the preceding activities). This phenomenon also makes it possible for people with high and low voices to sing the same thing together, but in ranges that are comfortable for everyone.

The octave is an interval: a distance between notes. Attuned listeners can not only distinguish notes from one another, but also intervals. To the practised ear, semitones sound like semitones, tones sound like tones, and octaves sound like octaves, no matter which notes are involved.

## Activity 8

Allow around 5 minutes

Using your keyboard, play C and the D♭ next to it simultaneously, noticing the ‘crunch’ of the semitone. Next, play D and E simultaneously, noticing how this interval also crunches, but not quite as sharply. Finally, play any two Gs together, and notice the relative smoothness or similarity of the two sounds.

### Discussion

What you heard were the distinct characteristics of three different intervals. Many trained musicians can identify the quality of an interval (e.g., whether they are hearing a tone or a semitone) by ear, without being told which notes are in play. You too can learn to do this with practice!

The following sections expand on concepts introduced earlier, including pitch, pitch system, octave, interval and frequency. These provide a starting point for thinking about how pitch systems are organised more globally.

OpenLearn - Introduction to music theory 2: pitch and notation
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