P33

Objectives

By the end of this chapter you will be able to:

  • Explain what a bassline is and why every song needs one.
  • Write a simple bassline using the PO-33’s melodic slots.
  • Use the root and fifth of a chord in your bassline.
  • Recognise a bassline in popular music.

Musical concept: what is a bassline?

A bassline is a low-pitched melody that runs underneath the main melody. The bassline provides harmonic foundation — it tells the listener what chord is playing. The kick drum provides rhythmic foundation; the bassline provides harmonic foundation.

In a 4-piece band (bass, drums, guitar, vocals), the bass plays the bassline. In a 4-voice PO-33 (kick, snare, hi-hat, melody), the bass plays the bassline — using one of the melodic slots.

The bassline is usually played in octaves below the main melody. If the main melody plays C4 (middle C), the bass plays C3 (one octave below). The PO-33’s melodic slots play at their recorded pitch by default. To make a slot sound “bass-like”, record a low-pitched sound (a low vocal, a sampled bass guitar, a synth bass patch) into it. Or use Tweak Tone to pitch-shift a recorded sample down.

Sidebar — Allen on basslines. Allen (Music Theory for Electronic Music Producers) emphasises that the bassline is what holds the song together. A great melody with a weak bassline sounds thin. A weak melody with a great bassline sounds full. The bassline is more important than the melody.

The root and the fifth

Most basslines use only two notes: the root and the fifth of the chord. In C major:

  • Root: C.
  • Fifth: G.

A bassline that alternates C and G will work for almost any chord in C major. This is the simplest possible bassline — and it is the foundation of half of all pop music.

For a more interesting bassline, add the octave (C → C, one octave up) and the third (C → E for major, C → D# for minor).

The classic pattern: root → fifth → octave → fifth. In C major on PO-33 pads:

  • Pad 1 ©: root.
  • Pad 8 (G): fifth.
  • Pad 13 (C, one octave up): octave.
  • Pad 8 (G): fifth.

Played as a sixteenth-note pattern: 1, 8, 13, 8, 1, 8, 13, 8. This is the bassline of “Another One Bites the Dust” by Queen (1980) — almost exactly.

How to write a bassline on the PO-33

The PO-33’s bassline is just another melodic slot. Use slot 2 for the bass (slot 1 is reserved for the lead melody; we will reserve slot 3 for a pad chord in Chapter 10).

To write a bassline:

  1. Record a low-pitched sound into slot 2 (hum a low note, sample a bass guitar, etc.).
  2. Use Tweak Tone to lower the pitch by 12 semitones (one octave) if needed. Knob A in Tweak Tone mode shifts pitch.
  3. Press WRITE, PLAY.
  4. On step 1, press pad 1 (root).
  5. On step 5, press pad 8 (fifth).
  6. On step 9, press pad 13 (octave).
  7. On step 13, press pad 8 (fifth).
  8. Press WRITE to exit.

You have written a basic bassline. It plays under whatever other patterns you have in slots 9, 10, 11 (drums) and slot 1 (lead melody).

Sidebar — the PO-33’s voice limit. The PO-33 plays 4 voices simultaneously. If you have kick + snare + hi-hat + bass, that’s 4 voices — no headroom for a melody. To add a melody, either remove the hi-hat (and play hats on a separate pattern) or skip the bassline and let the bass be the melody. We’ll discuss voice management in Chapter 16.

Guided exercise: the C-G bassline

Success criteria: a bassline that plays C → G → C → G → C → G → C → G over 8 steps.

  1. Record a low sound into slot 2. If you don’t have a bass, hum a low note and pitch-shift it down.
  2. Press WRITE, PLAY.
  3. On steps 1, 3, 5, 7, 9, 11, 13, 15: press pad 1 ©.
  4. Press WRITE to exit.

Wait, that’s just a constant C. Let me give you a better exercise:

  1. Record a bass sound into slot 2.
  2. Press WRITE, PLAY.
  3. Step 1: pad 1 ©.
  4. Step 3: pad 8 (G).
  5. Step 5: pad 13 ©.
  6. Step 7: pad 8 (G).
  7. Step 9: pad 1 ©.
  8. Step 11: pad 8 (G).
  9. Step 13: pad 13 ©.
  10. Step 15: pad 8 (G).
  11. Press WRITE to exit.

This is an 8-note bassline that alternates root and fifth. It will sound “steady” and “anchored”. Pair it with a drum beat from Chapter 4 (kick on 1+9, snare on 5+13, hat every odd step) and a melody from Chapter 7 (a C major scale melody). You have a complete song.

Creative challenge: the walking bassline

A walking bassline is a bassline that plays a different note every beat. In jazz, walking basslines are the norm. In pop, walking basslines are less common but can add movement.

Write a walking bassline in C major:

  • Step 1: pad 1 ©.
  • Step 3: pad 3 (D).
  • Step 5: pad 5 (E).
  • Step 7: pad 6 (F).
  • Step 9: pad 8 (G).
  • Step 11: pad 10 (A).
  • Step 13: pad 12 (B).
  • Step 15: pad 13 ©.

This is a “scale-walking” bassline. It moves stepwise up the C major scale. Pair it with a slow tempo (80 BPM) and a chord progression (we’ll learn this in Chapter 10) and you have a jazz-flavoured track.

Listening assignment

Listen to:

  • Queen, “Another One Bites the Dust” (1980). The bassline is C → G → C → G → C → G → C → G. It is exactly the bassline we just wrote. The song is built on that bassline.
  • Daft Punk, “Around the World” (1997). The bassline is a single note repeated — G, G, G, G. Sometimes it adds an F. It is the simplest possible bassline, and the song is one of the biggest dance hits of all time.
  • Pink Floyd, “Money” (1973). The bassline is in 7/4 time (an unusual time signature) and uses a minor scale. It is one of the most famous basslines in rock history.
  • Michael Jackson, “Billie Jean” (1982). The bassline plays the root and fifth of the chord, alternating every beat. Classic disco-funk.

Summary and checkpoint

Key takeaways:

  • A bassline is a low-pitched melody that provides harmonic foundation.
  • The most common bassline notes are the root and fifth of the chord.
  • On the PO-33, the bassline lives in a melodic slot (slot 2 is a good choice).
  • Watch the 4-voice polyphony: bass + 3 drums fills the device.

Self-check:

  • [ ] Can you write a C → G → C → G bassline?
  • [ ] Can you record a low-pitched sound into slot 2?
  • [ ] Do you understand why the bass plays the root and fifth?
  • [ ] Can you pair a bassline with a drum beat and a melody without exceeding 4 voices?

If you answered “yes” to all four, move on to Chapter 10.