Harmony, Rhythm & Instrumentation
Harmony, Rhythm & Instrumentation
This lesson covers the final three musical elements you need for the exam: harmony (chords and progressions), rhythm (time signatures, devices and tempo) and instrumentation (acoustic and electronic instruments, plus DJ technology).
Harmony
Harmony is created when two or more notes sound together. The building blocks of harmony are chords.
Chord Types
You need to know seven chord types:
- Major — sounds bright and happy. Built from root, major 3rd, perfect 5th.
- Minor — sounds sad or dark. Built from root, minor 3rd, perfect 5th.
- Diminished — sounds tense and unstable. Built from root, minor 3rd, diminished 5th.
- Augmented — sounds unsettled and dreamlike. Built from root, major 3rd, augmented 5th.
- Minor 7th — a minor chord with an added minor 7th. Warm, jazzy character.
- Major 7th — a major chord with an added major 7th. Smooth, sophisticated sound.
- Suspended (sus) — replaces the 3rd with a 2nd (sus2) or 4th (sus4), creating an unresolved, open sound.
Seven chord types: major (bright), minor (sad), diminished (tense), augmented (dreamlike), minor 7th (jazzy), major 7th (smooth) and suspended (unresolved). Know the character of each — this helps with analysis questions.
Chord Progressions
A chord progression is a sequence of chords that forms the harmonic backbone of a piece. Progressions can be:
- Diatonic — using only chords built from the notes of the key. These sound natural and expected.
- Chromatic — using chords that include notes from outside the key. These create surprise, tension or colour.
Rhythm
A time signature tells you how many beats are in each bar and what note value represents one beat.
Simple time — each beat divides naturally into two equal parts:
- 2/4 — two crotchet beats per bar (marches, polkas)
- 3/4 — three crotchet beats per bar (waltzes)
- 4/4 — four crotchet beats per bar (most pop, rock, hip-hop)
- 5/4 — five crotchet beats per bar (irregular, unsettling feel)
- 6/4 — six crotchet beats per bar
- 7/4 — seven crotchet beats per bar (progressive rock)
Compound time — each beat divides naturally into three equal parts, giving a swinging, lilting feel:
- 6/8 — two dotted-crotchet beats per bar (jigs, some ballads)
- 9/8 — three dotted-crotchet beats per bar
- 12/8 — four dotted-crotchet beats per bar (slow blues, gospel)
Rhythmic Devices
Rhythmic devices add interest and groove to music:
- Syncopation — placing accents on weak beats or off-beats, creating a sense of surprise and groove. Common in funk, jazz and pop.
- Triplets — three notes played in the time of two, creating a flowing, rolling feel.
- Dotted rhythms — a dot after a note adds half its value, creating a long-short pattern that gives energy and drive.
Tempo
Tempo is the speed of the music, measured in BPM (beats per minute). A slow ballad might be 60–80 BPM, a pop song 100–130 BPM, and a fast dance track 140–180 BPM. Tempo changes (accelerando for speeding up, rallentando for slowing down) add expression and drama.
Instrumentation
Instrumentation refers to which instruments are used in a piece. The spec divides instruments into acoustic, electronic and DJ technology.
- Strings — plucked (guitar, harp, banjo) or bowed (violin, viola, cello, double bass).
- Percussion — tuned (timpani, xylophone, vibraphone) or untuned (snare drum, bass drum, cymbals, tambourine).
- Keyboards — piano and organ.
- Brass — valved (trumpet, French horn, tuba) or slide (trombone).
- Woodwind — flutes (flute, piccolo) or reeds (clarinet, oboe, bassoon, saxophone).
- Vocals — lead vocals (main melody and lyrics) and backing vocals (harmonies and support).
Electronic instruments:
- Electric guitar and electric bass — use pickups and amplifiers to produce sound.
- Synthesiser — generates sound electronically using oscillators, filters and envelopes.
- Sampler — plays back recorded audio samples triggered by keys or pads.
- Drum machine — produces electronic or sampled drum sounds, programmed into patterns.
DJ technology:
- Turntables — play vinyl records, allowing scratching and beat-matching.
- CDJs — CD or USB-based players used by DJs for digital music playback.
- Mixer — blends audio from multiple sources with crossfader, EQ and effects.
- DJ software — applications like Traktor or Serato that provide virtual decks, effects and beat-matching tools on a laptop.
Acoustic instrument families: strings (plucked and bowed), percussion (tuned and untuned), keyboards (piano, organ), brass (valved and slide), woodwind (flutes and reeds), vocals (lead and backing). Know examples from each category.