The time signature tells us how many beats are in a measure and the type of note that receives 1 beat of time. A downbeat is the instant in time when each beat begins within the measure. If the time signature is 4/4, then there are 4 beats in the measure, which means that there are exactly 4 downbeats in the measure (1, 2, 3 and 4).
Starting on the Downbeat
Sometimes a rhythmic note starts on the downbeat – that is always the easiest situation. In the figure below, we have 1 measure of 4/4 time (4 beats in a measure, quarter note gets 1 beat).
- The red blocks above the measure indicate the length of time for each beat.
- The number in each block is the number of each beat in the measure.
- The arrows indicate where each downbeat occurs.
With 4 quarter notes in the measure, each quarter note starts on a downbeat – each quarter note lines up with the start of each of the 4 beats in the measure.
Notice that the beat (illustrated by the red block) lasts from when one downbeat occurs until the next downbeat occurs. The beat takes that entire amount of time (the entire red block). The downbeat is only the instant of time when the beat begins (the left edge of the red block).
Noteworthy: The concept of downbeat and upbeat only occurs when rhythmic notes are placed in a measure with a time signature. These concepts exist to describe where the rhythmic note appears in the measure and how it relates to the beats of the measure given its placement among the other rhythmic notes.
Sometimes a single note will span multiple beats so that a new note does not start on all 4 downbeats in the measure – however, the measure does still have 4 beats in it!
In the example below:
- The quarter notes start on the downbeat of beats 1 and 2.
- The half note starts on the downbeat of beat 3 and continues through the end of beat 4 (because it lasts for 2 beats).
- No notes begin on the downbeat of beat 4.
A trickier situation is when notes begin in places other than the downbeat. We can see where the downbeat is in the red block – it is the left edge of the block. We use another point to divide the beat in half when we play smaller rhythmic notes. The point in the middle of the beat is called the upbeat.
In the figure below, a grey line has been added to the red block that represents the upbeat of each beat. Remember:
- The beat is the entire time represented by the red block.
- The downbeat is the instant that the beat begins in a measure (left edge of the red block).
- The upbeat is the instant in the center of each beat (grey line with up arrow) in the measure.
Noteworthy: The upbeat allows us to measure half of a beat. The time from an upbeat to the next downbeat is half of a beat, as is the time from a downbeat to the next upbeat.
Notice that the first quarter note in the measure starts on the upbeat of beat 1 in the measure and the second eighth note starts on the upbeat of beat 2 in the measure.
Also notice that the first quarter note starts at the upbeat of 1, continues through the downbeat of 2, and ends just before the upbeat of 2; the 2nd and 3rd quarter notes include the downbeat and upbeat of the 3rd and 4th beats respectively.
Either way (upbeat-downbeat or downbeat-upbeat), a quarter receives one full beat of time. In the case of the upbeat to downbeat quarter note, it receives half a beat from beat 1 and half a beat from beat 2, making one full beat of time.