Music Theory from Zero

This guide covers what you need to start writing music in Bangerator. It assumes no previous knowledge. Every term is explained the first time it appears, and the ▶ buttons play each example.

1Notes and pitch

Sound is vibrating air. Fast vibration sounds high and slow vibration sounds low. How high or low a sound is called its pitch.

A note is a sound with a steady, recognizable pitch, like a sung tone or a guitar string. Most drum sounds have no clear pitch, so Bangerator gives drums their own grid.

2The 12 notes

Western music uses 12 notes that repeat over and over, each set higher than the last. On a piano, the 12 notes are the white and black keys together, and the pattern of keys repeats across the keyboard.

The distance from one key to the very next one (white or black) is the smallest step in this system. It’s called a half step (or semitone).

After 12 half steps you reach the same note again, only higher. This distance is an octave. Two notes an octave apart sound so similar that they get the same name. When a man and a woman sing the same melody together, they’re often an octave apart.

3Half steps and whole steps

• Half step (H): move 1 key.
• Whole step (W): move 2 keys (two half steps).

These two step sizes are the building blocks of scales.

4Scales

Playing all 12 notes freely tends to sound random. A scale is a chosen set of notes, usually 7 of the 12, that sound good together. A scale is defined by the pattern of steps between its notes.

The pattern for the major scale is:

W  W  H  W  W  W  H

You can start the pattern on any of the 12 notes. The result is always a major scale, just higher or lower.

5Scale degrees: why Bangerator uses numbers

The notes of a scale are numbered in order: the first note is 1, the second is 2, up to 7. After 7 the scale starts again at 1, an octave higher. These numbers are called scale degrees.

1 is the tonic, or home note. Melodies tend to feel finished when they end on it and unfinished when they stop anywhere else.

Two settings decide what the numbers sound like:

• The key decides which of the 12 notes is 1.
• The scale decides which notes the other numbers point to.

Because of this, a melody written as numbers sounds like the same tune in any key. 1 1 5 5 6 6 5 is the start of “Twinkle Twinkle Little Star”:

Every row in Bangerator’s grid is a scale degree. When you change the key, the whole song moves with it and nothing needs rewriting.

Why most music software doesn’t do this

Most DAWs (FL Studio, Ableton and so on) store notes as fixed pitches. They can highlight the scale in the piano roll, but when you change the scale your notes stay exactly where they were. Notes that aren’t in the new scale now clash, and you have to find and move each one by hand.

Bangerator can behave that way too, so you can hear the difference. Above the grid, set “When the scale changes, notes…” to keep their pitch (DAW) and change the scale. The riff doesn’t move, the out-of-scale notes get a red dashed outline, and a counter shows how many there are. Snap to scale moves each one to its nearest scale note, which is what DAWs offer, but that rarely sounds as intended. Switch back to follow the scale and a scale change moves every note to the right place for you.

Degrees with their own names

6Major and minor

The natural minor scale uses the pattern W H W W H W W. Compared with major, three of its notes are a half step lower: ♭3, ♭6 and ♭7. The symbol ♭ (flat) means “a half step lower than in the major scale”. ♯ (sharp) means “a half step higher”.

Major usually sounds bright or happy, and minor usually sounds darker or sadder. The biggest cause of that difference is the third degree: a 3 sounds major and a ♭3 sounds minor.

In Bangerator, the small grey label next to each row number (for example ♭3) shows how that note compares with the major scale.

7Modes

If you take the notes of a major scale but treat a different note as home, you get a new scale with a different character. These are called modes. Ordered from brightest to darkest:

Each mode differs from its neighbor in the list by only one note. That’s why swapping scales on an existing loop works well: most notes stay the same and one or two change the mood. The ☀ Brighter and ☾ Darker buttons in the sidebar move through this list.

Other scales in Bangerator

8Pentatonic and blues scales

A pentatonic scale has five notes. It leaves out the two notes of the major or minor scale that most easily clash with others, so almost any combination of the remaining notes sounds fine.

• Major pentatonic: 1 2 3 5 6. Bright, common in pop and folk.
• Minor pentatonic: 1 ♭3 4 5 ♭7. Common in rock, hip-hop and blues.
• Blues: minor pentatonic plus one extra note between 4 and 5 (shown in Bangerator as ♯4).

9Chords

A chord is several notes played at the same time. The standard way to build one from a scale is to take every other note: start on a degree, skip one, take one, skip one, take one.

Starting on 1 gives 1-3-5. Starting on 2 gives 2-4-6, and so on. A three-note chord built this way is a triad. The note the chord is built on is its root.

Chord types

10Roman numerals

Chords are numbered with Roman numerals so they aren’t confused with melody degrees:

• Uppercase (IV) means a major chord.
• Lowercase (vi) means a minor chord.
• ° (vii°) means diminished.
• ♭ in front (♭VII) means the chord’s root is a half step lower than in the major scale.

The chords of the major scale are I ii iii IV V vi vii°. The chords of natural minor are i ii° ♭III iv v ♭VI ♭VII.

Musicians describe songs this way. “I–V–vi–IV” tells you exactly which chords to play in any key. Bangerator shows the numeral on every chord.

11Home, Away and Tension

Chords tend to play one of three roles. Bangerator colors each chord by its role:

A very common pattern is Home → Away → Tension → Home.

Cadences

A cadence is a pair of chords that ends a musical phrase, a bit like punctuation ends a sentence.

The What comes next? panel in Bangerator uses these patterns to suggest the next chord.

12Chord progressions

A chord progression is a sequence of chords. In pop and electronic music it’s often four chords, one per bar, repeated as a loop.

The Famous progressions list in the sidebar adds any of these with one click. They’re stored as numbers, so you can change the scale afterwards and hear the same progression with a different mood.

13The circle of fifths

The circle of fifths arranges the 12 keys around a circle. Each step clockwise moves up by a fifth (7 half steps, the distance from degree 1 to degree 5).

The useful part: keys next to each other share 6 of their 7 notes, while keys on opposite sides share very few. Neighboring keys and chords sound good together.

Reading the circle in Bangerator

• Outer ring: major chords. Middle ring: minor chords. Inner ring: diminished chords.
• The chords that belong to your current key are colored by role and labeled with their Roman numeral. Home (I) has a white outline.
• In a major key these chords sit together in one block: IV to the left of I, V to the right, and the related minor chords below them.
• The dots on the outer edge show the notes of your scale.
• Clicking a key moves your song to that key. Your numbers stay the same.

Relative major and minor

Each major key has a relative minor directly inside it on the circle (C major and A minor, for example). They use exactly the same notes, only with a different home note. That’s why A minor starts on degree 6 of C major.

Key signatures

A key signature is the number of sharps or flats a key uses. C major has none. Each step clockwise adds one sharp (G has 1, D has 2…), and each step counter-clockwise adds one flat (F has 1, B♭ has 2…). The center of the circle shows the count for your key.

Why fifths matter

The chord on 5 pulls strongly back to 1. Many progressions move counter-clockwise around the circle, with each chord acting as the “V” of the next: vi → ii → V → I.

14Rhythm: beats, bars and steps

• Beat: the steady pulse you’d tap your foot to.
• BPM (beats per minute): the tempo. Roughly: 70 is slow, 90–100 is typical hip-hop, 120–128 house, 140 dubstep and trap, 170+ drum & bass.
• Bar (or measure): a group of 4 beats, counted “1 2 3 4, 1 2 3 4”.
• Step: Bangerator divides each beat into 4 steps (16th notes), so one bar has 16 steps. Grid lines are thicker on every beat and thickest on every bar.
• Loop length: how many bars play before the loop repeats. 4 or 8 bars is typical.

Swing

Without swing, all steps are exactly equal in length. Swing delays every second step slightly, giving a “long-short, long-short” feel that sounds looser and more human. Around 10–30% works well for hip-hop and house.

15Drum patterns

The drum grid is a step sequencer. Each row is a drum sound and each box is a step. A lit box means that drum plays on that step.

Four on the floor (house, techno, disco)

Boom-bap (hip-hop)

Trap

Accents: Shift+click (or right-click) a step to make it louder. Mixing loud and quiet hi-hats makes a pattern sound less mechanical.

16Basslines

The bass connects the drums and the chords. A simple bassline that almost always works is to play each chord’s root, low, following the rhythm of the kick drum.

• If the chord is vi, play degree 6 in the bass. If it’s IV, play 4.
• For more movement, add the chord’s fifth, or the root an octave higher.
• 808-style bass usually uses long notes, one per kick.

In Bangerator, the rows tinted in a chord’s color are the notes of that chord. The most strongly tinted row is the root, which is the safest bass note.

17Writing melodies

1. Use chord notes on strong beats. The tinted rows are the notes of the current chord. Placing those on beats 1 and 3 makes the melody fit the harmony.
2. Mostly move by step. Moving to a neighboring degree (3 → 4) sounds smooth. Larger jumps (1 → 6) add energy. After a big jump, stepping back the other way usually sounds natural.
3. Repeat with variation. Repeat a phrase, then change its ending. Repetition makes a melody memorable.
4. Leave space. Rests (silence) are part of a melody.
5. Choose your ending. Ending on 1, 3 or 5 sounds finished. Ending on 2 or 7 sounds like it’s waiting for an answer.

If you have a melody but no chords, press ✨ Chords for my melody and Bangerator will pick chords that contain your melody notes.

Notes outside the scale

Now and then a note outside the scale adds useful color. Shift+click a note in Bangerator to raise it (♯) or lower it (♭) by a half step. These notes are most effective when used sparingly.

18Sound design: waves and envelopes

The four basic waveforms

A synthesizer starts from a simple repeating wave. The shape of the wave determines its basic tone:

Smooth waves like the sine contain only one frequency. Waves with sharp corners, like square and saw, also contain many higher frequencies called harmonics, which make them sound brighter.

The envelope (ADSR)

An envelope controls how a note’s volume changes over time, from the moment it starts until it fades out.

The filter

A low-pass filter removes high frequencies. Lowering the cutoff makes the sound darker and more muffled. Resonance boosts the frequencies right at the cutoff, adding a sharper, whistling edge. Filter pluck opens the filter at the start of each note and then closes it, a very common sound for synth basses.

Pitch drop

If a note starts at a higher pitch and quickly slides down, a sine wave becomes the deep “boom” of an 808 bass. Bangerator’s “808 Sub” instrument works this way.

19MIDI

MIDI is a format for musical instructions, not sound. A MIDI file records which notes to play, when, for how long and how hard. Any instrument or software that understands MIDI can play it back with its own sounds.

• Export MIDI saves your song as a .mid file that you can open in FL Studio, Ableton, Logic, GarageBand and most other music software.
• MIDI output sends notes live to other music software or a hardware synthesizer while Bangerator plays (Chrome and Edge only).

MIDI numbers notes from 0 to 127. Middle C is 60, each half step adds 1, and each octave adds 12.

20Quick reference

Glossary