In a DAW's piano roll, the distance between notes is already visible as a number of cells. Intervals are the names given to those distances. Once you can count them, you can move chords and melodies anywhere.
Part two stacked chords and part four moved melodies around. Both were really about the distance between notes — we just never named those distances. Time to name them.
What do I gain by naming distances?
Equal distances sound the same. Learn the distance from C up to E and you can measure it from F, or from A, and get the same brightness. A song survives a key change because the distances survive it.
The same distance sounds the same at any height.
Count in semitones
The reliable way to count is one key at a time on the keyboard, black keys included. C to the black key above it (C♯) is one; C to D is two. In a DAW's piano roll, one cell vertically is one semitone.
The distances to know first
You do not need all of them. These nine cover most of what you will meet; the number in brackets is the count of semitones.
- Semitone (1)
- Immediate neighbours. Muddy when sounded together — this is the clash in chapter 27.
- Whole tone (2)
- Skipping one. Feels like walking straight up. Most scale steps are this.
- Minor third (3)
- Up to the middle note of a minor chord. This is where dark comes from.
- Major third (4)
- Up to the middle note of a major chord. This is where bright comes from.
- Perfect fourth (5)
- Up to the note in sus4. Common in melodies too, and it does not clash.
- Tritone (6)
- Also called an augmented fourth or diminished fifth. The tension inside a seventh chord (chapter 31).
- Perfect fifth (7)
- The outer edge of a chord. It does not muddy, so it is safe even low down.
- Minor seventh (10)
- Up to the top note of C7. The backbone of rock and blues.
- Octave (12)
- Back to the same note name. Different height, same family (chapter 2).
- C–EMajor third (4) — bright
- C–E♭Minor third (3) — dark
- C–GPerfect fifth (7) — neither, and stable
Chapter seven said "lower the middle note by a semitone and it becomes minor". In today's vocabulary: you turned a major third into a minor third. Same action, more words available.
Generate over a simple progression while thinking about distance. Look at how many cells apart the neighbouring notes are.
Generate over C, F, G, CCount distance in semitones. The same distance sounds the same at any height.
Quick review
Everything here is answerable from this chapter. Pick an option and the answer appears straight away.
Question 1
How many semitones from C up to E?
Question 2
Move the same distance to a different height and what happens?