Note Lengths: Whole, Half, Quarter, Eighth

In the piano roll, a note isn't a dot: it's a rectangle. Its left edge tells you when it starts, and its length tells you how long it lasts. Listen to the same little melody twice. In the first version, each note holds until the next one.

Now here's the same melody, with exactly the same starting points, but with notes that last only one step each.

The first version sings; the second one hops. Yet no pitch and no starting point has changed. Note length is a full part of rhythm, and to talk about it precisely, music has given a name to each length.

Lengths that split in two

The system is simple: each length is worth half of the one before. Let's start with the longest one you'll use often, the whole note, which lasts four beats, so one full bar of 4/4. Cut it in two and you get the half note, which lasts two beats. A half note cut in two gives the quarter note, which lasts one beat. The quarter note cut in two gives the eighth note, half a beat, and the eighth note cut in two gives the sixteenth note, a quarter of a beat. You can keep going with the thirty-second note, which lasts an eighth of a beat.

Listen to these four bars: a whole note, then two half notes, then four quarter notes, then eight eighth notes. A little rim click marks each beat. The tempo stays the same from start to finish; only the notes split in two with each bar.

The nice thing about the American names is that they're already fractions, and your software's menus use the same fractions. The whole note is written 1/1, the half note 1/2, the quarter note 1/4, the eighth note 1/8, the sixteenth note 1/16 and the thirty-second note 1/32. The fraction tells you what share of the whole note the note takes up. That's exactly what you're choosing when you set the grid or the length of a note. In British English, the same lengths are called semibreve, minim, crotchet, quaver, semiquaver and demisemiquaver, and you'll come across those names in UK tutorials and books.

The last column is the most useful day to day. On a 1/16 grid, the one most step sequencers use, a sixteenth note takes up one step, an eighth note two steps, a quarter note four, a half note eight and a whole note sixteen. The thirty-second note doesn't fit on this grid: to write it, you have to set the grid to 1/32, which you'd do, for example, for very fast hi-hat rolls.

Rests have a length too

A rhythm is made of sounds and silences, and the silences count just as much as the notes. So each length has a matching rest. The rest that lasts a whole note is the whole rest; then come the half rest, the quarter rest, the eighth rest and the sixteenth rest, each one as long as the note it's named after. In the piano roll, you don't draw a rest: it's simply an empty space between two notes.

Listen to this two-bar melody. It uses only a few notes, and it's the rests that give it its character: a quarter rest after the first phrase, eighth rests that let it breathe, and a final quarter rest before the loop starts over.

If you filled those silences by stretching the notes, the melody would run out of breath. When you're starting out, you often want to fill every cell of the grid; with experience, you start asking what you can take away instead. Silence leaves room for the kick, for the vocal, or simply for the listener's ear.

Tied notes

In sheet music, a length that has no name of its own, or that spills over into the next beat, is written with a tie: a small curve that connects two notes of the same pitch. The second note isn't played again; it extends the first one. A quarter note tied to an eighth note, for example, gives a single note that lasts a beat and a half, or six steps.

In the piano roll, the tie doesn't exist as a symbol: you simply draw a longer note. But you can clearly hear the difference between two separate notes and a tied note. In the next figure, the first half of the bar has two quarter notes of the same pitch, each struck separately; the second half has a single eight-step note, the equivalent of two tied quarter notes.

Why does sheet music need ties? Because sheet music has to show where the beats fall, so the musician can read without counting every cell. Your piano roll shows everything on a grid, so a long note is enough. You'll still run into the word if you read sheet music, or if your software displays your notes as a score.

Length in your software, and gate

In MIDI, each note has a start and an end, and the length between them is what you set when you stretch the rectangle. For a piano, a bass or a pad, that length matters a lot: the sound holds as long as the note lasts, then it fades out more or less quickly depending on the instrument's release setting. For an 808, the length often decides how long the bass rings: an 808 that's too long spills over the next kick, and one that's too short leaves a gap.

For many drum sounds, on the other hand, length barely matters. A kick or a clap is often played as a “one shot”: the sample plays all the way through, whether the note lasts one step or one bar. That's why the step sequencer usually only asks you for note starts.

In arpeggiators and synth sequencers, note length is often set with a parameter called gate. It's expressed as a percentage of the time between two notes of the arpeggio: at 100%, each note holds until the next; at 50%, it lasts only half that time, and the sound becomes more detached. Listen to the same series of eighth notes with a long gate, then with a short gate.

The second bar breathes more: each note leaves a small silence before the next one. Neither is better; it's a choice of character, just like the choice of notes.

All of these lengths split in two. In the next lesson, we'll see the two ways out of that system: the dot, which makes a note half again as long, and the triplet, which fits three notes where only two would usually go.