The Definition of Beats
People often comment that a song has a nice beat, when what they are referring to is the song’s rhythm. Although beat and rhythm are often used interchangeably, they are not the same. Rhythm deals with the relative duration of sound, whereas beat is a unit of measurement.
When we measure the physical length of a thing, we may do so using different units of measurement, such as inches, feet, miles, etc. Let’s say that we want to measure something using inches. When we do so, we are designating the inch as our unit of measurement by assigning to it a value of “1”. We can apply this same concept of measurement to musical notes; but instead of measuring physical length we will be measuring duration of time.
Any type of note may be chosen as a unit of measurement if we assign to a value of “1”. By assigning a value of “1” to the quarter note we are designating the quarter note as the “beat” or the “unit of measurement” by which we will measure the duration of all other notes. From the previous chapter, we learned that the duration of a quarter note is one quarter the duration of a whole note. If we assign the value of “1” to the quarter note, the whole note will therefore be equal to a value of “4”. In musical terms, when a quarter note equal to one beat, the whole note equal to four beats.
Also, if we assign a value of “1” to the quarter note, the half note will therefore be equal to a value of “2”. In musical term, when a quarter note equals one beat, the half note equals two beats. Remember: a half note is not a half of a beat. Its name comes from its relation to the whole note. We also know from the previous chapter that the duration of a quarter note is twice the duration of an eighth note. If we assign a value of “1” to the quarter note, the eighth note will therefore be equal to a value of “1/2”. In musical terms, when a quarter note equals one beat, the eighth note equals ½ of a beat.
An eighth note is not an eighth of a beat and sixteenth note is not a sixteenth of a beat. Its name comes from its relation to the whole note. We know that the duration of a quarter note is four times the duration of a sixteenth note. If we assign a value of “1” to the quarter note, the sixteenth note will therefore be equal to a value of “1/4”. In musical terms, when a quarter note equals one beat, the sixteenth note equals ¼ of a beat.
Here is a helpful chart that shows the quarter note as the unit of measurement and its relations to all the other notes.
Beat Vs. Tempo
It is a common mistake for beginner music students to associate “1 beat” with “one second” of time. When we assign numerical values to notes we are not designating that they be played for any specific amount of time. The actual time it takes to play a note is determined by something called tempo. Tempo is Italian word for “rate of speed”. When the tempo of a song is quick, the beats will be occurring at a much faster rate and therefore the durations of the notes in actual time will be shorter. When the tempo of a song is slow, the beats will be occurring at a much slower rate and therefore the durations of the notes in actual time will be longer.
A whole note has a numerical value of four beats, its duration may be longer or shorter depending on how quickly or slowly the beats occur in actual time. When beats occur at a faster rate, the whole note will be played for a shorter period of time.
The tempo is always indicated above the first measure of music in a song, usually with a metronome marking. (A metronome is a mechanical device that keeps track of musical time.) Here is an example of metronome marking.
This marking indicates to the performer that they are to play at a rate of 120 “beats per minute” or “BPM”.
Up until the early 19th century, tempo was indicated with Italian words above the first notes of a song. For example, the word “Allegro” placed at the beginning of a song would to the performer that they have to play quickly. This method is not precise as metronome markings, since the word only give the performer a rough idea of the tempo and does not indicate an exact measurable speed. Here is a list of some common tempo markings.
Largo = very slow
Adagio = slow
Andante = a medium slow tempo
Moderato = Medium
Allegretto = Not as fast as allegro
Allegro = fast
Presto = very fast
Prestissimo = very, very fast.
Here is another list with modern day metronome (beat per minute) equivalents.
Largo (40-60 bpm)
Adagio (66-76 bpm)
Andante (76 – 108 bpm)
Moderato (101 –110 bpm)
Allegro (120 – 139 bpm)
Presto (168 – 200 bpm)
Prestissimo (over 200 bpm)