Beat and Meter
The organization of time in music is just as fundamental (if not more so) than the system of pitches. Harmony depends on certain pitches being played synchronously, and melodies are shaped just as much by their rhythms as they are by their melodic contours. Many percussion instruments don't produce definite pitches at all, making them solely rhythmic instruments. In this section, we will discuss how music is organized in time through beat and meter, and in the next section we will cover rhythm itself.
Beat
The foundation of music in time is the steady pulse of the beat. The beat is what we dance to, what a conductor indicates, and what a metronome produces. The vast majority of music has a beat, even if it is not always apparent to the listener.
Tempo
The tempo is the speed of the beat. A tempo may be designated with terms such as fast or slow, or it can be measured precisely in beats per minute (bpm). The second-hand of a clock ticks at 60bpm, which is a good reference point.
It is common to find tempo markings in Italian (very fast: presto, slow: lento) or another language such as French or German. Although some terms can be understood by consulting a standard bilingual dictionary, other terms are conventional rather than literal. For example, allegro literally means 'happy' or 'cheerful' in Italian, but in music allegro means fast.
| Tempo Marking | Description | BPM |
| grave | solemn (very, very slow) | ~ 40 |
| largo | broad (very slow) | ~ 50 |
| adagio | quite slow | 60-70 |
| andante | walking pace | 80-100 |
| moderato | moderate | ~ 110 |
| allegro | fast | 120-160 |
| vivace | lively | ~ 140 |
| presto | very fast | ~ 180 |
Measuring tempo in beats per minute can seem very rigid, but sometimes a soloist is permitted to slow down and speed up the tempo slightly for expressive purposes. This is called rubato or tempo rubato from the Italian for 'stolen time'. For more on this, see the section on melody, harmony, and meter below.
Meter
a measure
Meter is the result of grouping beats together into regular sets. In notation, each group of beats is contained in a measure (or bar), which is separated from the next measure with a vertical line, or barline. The first beat of each group is the strongest and is called the downbeat. In the patterns that conductors use to indicate meter, the downbeat is always indicated by a large downward motion (see the conducting patterns below). The last beat in a measure is the weakest, and is called the upbeat. When a melody begins with an upbeat instead of a strong downbeat, this is called a pickup or anacrusis.
Duple, Triple, and Quadruple Meter
When the beats of a piece are grouped by two (often going STRONG, weak, STRONG, weak, like a march), this is duple meter. When the beats are grouped by three (often STRONG, weak, weak, STRONG, weak, weak, as in a waltz), the meter is triple. It is also common to have quadruple meter, but in many ways it is a variation of duple meter, so we will group them together and call them both duple. It is possible to have 5 beats (quintuple meter) or more in each measure, but that is fairly uncommon. To the right are the patterns that conductors use for duple, triple, and quadruple meters.
Time Signatures
In notation, meters are indicated by time signatures, which consist of two numbers - a top number and a bottom number. Usually the top number indicates how many beats there are in a measure, as in the conducting patterns above. Time signatures not only indicate if meters are duple, triple, or quadruple, but they also indicate the relationship between the rhythms and the beat. For more details about time signatures and how they work, see time signatures revisited in the advanced theory section.
Polymeter, Suppressed Meter, and Non-metric Music
Polymeter occurs when there are two or more meters occurring simultaneously. When this occurs, it can make the meter inaudible to listeners because there is too much complexity. It is also possible for meter to be ambiguous because the beat is unclear. In either case, whenever the meter cannot be determined without looking at the notation, we call this suppressed meter.
In some music, there is no meter audible in performance, nor visible in notation. An example of this is the Gregorian chant of the Medieval period, which consists of notated melodies without clear rhythmic indications. This type of piece is called non-metric.
The Interaction of Pitch Elements with Beat and Meter
fermata markings
Pitch elements (such as melodies and harmonies) interact with the beat and meter in particular ways. For example, a fermata indicates that a note or rest should be continued longer than its notated duration, which means that the beat must be paused for a brief time.
When a soloist is permitted to use rubato (see above), he will often slow down the tempo on the peak (highest note) of a phrase to emphasize the climax, or will slow down just before a cadence to prolong the listeners' anticipation of a harmonic and melodic resolution. When his melody descends, a soloist will sometimes speed up, emulating the way an object will gain momentum as it falls.
In terms of meter, both melodies and harmonies follow certain patterns. Melodies often fit neatly within the measures defined by the meter. To put it another way, the lengths of the melodic phrases are compatible with the meter of the piece. Particularly in vocal music, it is very common to find 4-measure phrases, one after the other.
Harmonic Rhythm and Lead Sheets
Harmonies also fit with meters in certain ways. The rate at which harmonies change is known as harmonic rhythm. Just as the rhythms of melodies can fit into the meter, harmonic rhythms often do too. Harmonic rhythm is particularly clear on a lead sheet. A lead sheet is a type of sheet music that shows the melody of a tune as well as the harmonies that should accompany that melody. Lead sheets are very common in jazz and are occasionally used in popular music and elsewhere.
As you can see in the example above, the melody is notated on the staff and chord symbols are used above the staff to indicate harmonies. The chord symbols used in lead sheets are different from the Roman numeral system that we have already discussed (see the section on harmony). The Roman numeral system is used to show the relationships between chords (i and V, for example), but does not tell us which pitches appear in those chords unless we also know the key of the piece (for example, i in the key of A minor is an A minor chord, V in the key of A minor is an E major chord). For lead sheets, the name of the root pitch is given, which allows us to determine all the specific pitches of the chord (E = E major chord). The other numbers, letters, and symbols that appear in chord symbols tell us the quality of the chord (major, minor, augmented, diminished), additional notes that should be added to the chord, and alterations that should be made to the pitches in the chord (inserting sharps, flats, or naturals).