Hear A–B–A: an 18-second music exercise
Can you spot the moment a tune comes back? This original Coru melody lasts 18 seconds. Listen for an opening idea, a change, and the opening again. You need no instrument or music-reading skills. If you prefer to work without sound, the numbered map below contains the whole exercise.
Listen before reading the answer
- Play the recording once at a comfortable volume. Notice when the music changes and when something feels familiar. Write down your best guess for the return time.
- Replay it. Remember just the first three notes: they climb, and the third lasts longer. Listen for that same opening later.
- Check the map below, then listen once more without watching the time. Your task is to recognise a specific pattern, not to name the notes.
Original Coru melody: A–B–A
Transcript
Instrumental melody; no speech. 0:00–0:06, A: the first three notes rise and the third is longer. The melody moves down and ends on its starting note. 0:06–0:12, B: four short notes alternate in a higher register; two longer notes follow, then another group of four short notes and two longer notes. 0:12–0:18, A: the complete opening six seconds return exactly, with the same pitches, lengths and sound. The underlying tempo stays the same throughout; there is no change of instrument. The numbered map below gives every note and its time slot.
Check the return
- 0:00–0:06 · A: Three opening notes climb. The third is longer; the melody then moves down and ends on its starting note.
- 0:06–0:12 · B: Four short notes alternate higher up. Longer notes follow, then another quick group and two longer notes.
- 0:12–0:18 · A: The complete opening six seconds return exactly: the same pitches, lengths and sound.
The answer
The answer is 0:12. The opening rise and longer third note are useful clues. B has quicker notes, but the underlying tempo stays the same. All three parts use the same sound, so a different instrument is not the clue here.
Do the whole exercise without sound
These numbers show relative pitch: a larger number means a higher note. The number in parentheses gives its time slot in seconds; each note fades just before the next slot. You do not need to know the note names. Read one row at a time, then compare the first and third rows.
0:00–0:06: 1(½), 3(½), 5(1), 3(½), 2(½), 1(1), 2(½), 0(½), 1(1).
0:06–0:12: 6(¼), 5(¼), 6(¼), 5(¼), 4(1), 3(1), 2(¼), 3(¼), 4(¼), 3(¼), 2(1), 5(1).
0:12–0:18: 1(½), 3(½), 5(1), 3(½), 2(½), 1(1), 2(½), 0(½), 1(1).
Which row returns? The third repeats every number and time slot in the first. The middle row differs in both pitch order and lengths. That comparison gives the same A–B–A map without audio.
What the letters tell you
A names the first idea; B names a contrasting one. Reusing A marks its return. This way of mapping repetition and contrast is explained in OpenLearn’s guide to letter labels.
Our short exercise practises recognising a return. A–B–A also appears in descriptions of ternary form, but those letters alone do not settle a full analysis: section proportions and the nature of the contrasting music also matter. Puget Sound’s music-theory text explains that distinction.
Try one change on paper: replace only the last 1 in the final row with 3. Most of A remains, but the ending changes. Label your version A–B–A′, with A′ meaning “A with a change.” Compare it with the exact return in the recording.