Objectives

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

Explain what BPM means and how it relates to note duration.
Cycle through the three BPM presets on the PO-33.
Fine-tune the BPM with Knob B.
Choose an appropriate BPM for your first beat.

Musical concept: what is a beat?

A beat is the regular pulse you tap your foot to. Almost all popular music has a regular beat. The beat is what makes you nod your head, tap your foot, or dance.

BPM (beats per minute) is the number of beats that fit into 60 seconds. At 60 BPM there is one beat per second. At 120 BPM there are two beats per second. At 180 BPM there are three beats per second.

Hewitt (Music Theory for Computer Musicians) introduces BPM as the practical answer to “how fast is the music?”. He notes that:

60–80 BPM is slow — ballads, slow rock, some hip-hop.
80–110 BPM is medium — most pop, R&B, hip-hop.
110–130 BPM is medium-fast — dance-pop, disco, house.
130–160 BPM is fast — techno, drum’n’bass, hardstyle.
160+ BPM is very fast — speedcore, some jungle.

The PO-33’s three presets are at 80, 120, and 140 BPM — slow, medium-fast, and fast. These three tempos cover most popular music genres. We will explore genre-specific tempos in Part IV.

The relationship between BPM and step duration

The PO-33’s 16 steps are sixteenth-notes. At 120 BPM:

One beat = 0.5 seconds.
One quarter-note = 0.5 seconds.
One eighth-note = 0.25 seconds.
One sixteenth-note (one PO-33 step) = 0.125 seconds.
One bar (16 steps) = 2 seconds.

At 80 BPM (Hip Hop):

One beat = 0.75 seconds.
One sixteenth-note = 0.1875 seconds.
One bar = 3 seconds.

At 140 BPM (Techno):

One beat ≈ 0.43 seconds.
One sixteenth-note ≈ 0.107 seconds.
One bar ≈ 1.71 seconds.

The same 16-step pattern feels different at different tempos. At 80 BPM it feels relaxed. At 120 BPM it feels groovy. At 140 BPM it feels urgent. This is one reason the PO-33 has BPM presets — different genres want different feels.

PO-33 Playback: setting the tempo

To cycle presets:

Tap the BPM button. The screen shows “HIP HOP 80”, “DISCO 120”, or “TENCHO 140”.
Tap again to cycle to the next preset.

To fine-tune:

Hold the BPM button.
Turn Knob B. The BPM changes in 1-BPM increments from 60 to 240.

Sidebar — swing. Hold BPM + turn Knob A to set the swing. The PO-33 has 8 swing levels (0–7). Swing makes off-beat steps play slightly late, which gives the beat a “shuffled” feel. We’ll explore swing in Chapter 6.

Why three presets?

The PO-33’s three presets are at 80, 120, and 140 because those are the tempos of three of the most popular genres in the PO-33’s lineage:

Hip Hop (80 BPM): classic boom-bap, J Dilla, Madlib. 80 BPM is the tempo of “Nuthin’ but a G Thang”, “C.R.E.A.M.”, “93 'til Infinity”.
Disco (120 BPM): classic disco, house, French house. 120 BPM is the tempo of “I Will Survive”, “Da Funk”, “One More Time”.
Tencho (140 BPM): techno, trance, hard house. 140 BPM is the tempo of “Spastik” by Plastikman, “Strings of Life” by Rhythm Is Rhythm.

If you start a beat and it doesn’t feel right, change the tempo first. It is the cheapest change you can make and the most impactful.

Guided exercise: the same pattern at three tempos

You will need: the pattern from Chapter 2 (sound on steps 1, 5, 9, 13).

Success criteria: you can hear the same pattern feel different at 80, 120, and 140 BPM.

Make sure your four-on-the-floor pattern is still in the sequencer. If not, redo Chapter 2’s exercise.
Set the BPM to Hip Hop (80). Press PLAY. Listen for 30 seconds.
Tap the BPM button to cycle to Disco (120). The pattern continues playing at the new speed. Listen for 30 seconds.
Tap the BPM button to cycle to Tencho (140). Listen for 30 seconds.
Cycle back to Hip Hop (80).

You should hear the same four hits per loop but at three different feels. The pattern is identical; the tempo is different.

Creative challenge: match the genre

For each of the following songs, set the PO-33’s BPM (using fine-tune with Knob B if needed) so that your pattern plays at the song’s tempo:

“Juicy” by The Notorious B.O. — around 97 BPM.
“Around the World” by Daft Punk — around 121 BPM.
“Windowlicker” by Apendix Twin — around 134 BPM.

Press PLAY on the PO-33 and listen to the song. Try to tap your foot in time with both. If they don’t sync, fine-tune Knob B up or down by 1 BPM at a time until they do.

Listening assignment

Listen to three songs at three tempos, all in the same session:

A Tribe Called Quest, “Can I Kick It?” (1991) — 96 BPM. Hip-hop, classic boom-bap. The bassline loops a single sampled phrase, the drums are a break chopped into pieces.
Daft Punk, “Around the World” (1997) — 121 BPM. House/disco. The bassline is a single repeated note, the drums are a four-on-the-floor.
Underworld, “Born Slippy .NUXX” (1995) — 137 BPM. Techno. The drums are a four-on-the-floor with off-beat hi-hats.

Notice how the same drum pattern (kick in the same step positions) would feel different at these three tempos. Then notice how each song’s drum pattern is actually different — they’re not just the same pattern at different tempos. Producers pick patterns that fit the tempo, not just play at it.

Summary and checkpoint

Key takeaways:

BPM = beats per minute. The PO-33’s presets are 80, 120, 140.
One step is a sixteenth-note. At 120 BPM, one step is 0.125 seconds.
The same pattern feels different at different tempos. Change tempo first if your beat doesn’t feel right.
Fine-tune BPM from 60–240 by holding BPM + turning Knob B.

Self-check:

[ ] Can you cycle through the three BPM presets?
[ ] Can you fine-tune the BPM by 1 BPM with Knob B?
[ ] Do you understand why a “kick on every step” pattern feels different at 80 vs. 140 BPM?
[ ] Can you tap your foot to a song and the PO-33 simultaneously?

If you answered “yes” to all four, you are ready for Part II: rhythm and beat.

Part II — Rhythm and Beat

By the end of Part I you have a single sound that plays on four steps of a 16-step sequencer. That is technically a beat, but it is not yet interesting. A real beat has at least three sounds (kick, snare, hi-hat) and they play at different densities. Part II teaches you the building blocks of rhythm — how to layer drum sounds, how to slice a break, and how to make the beat swing.