The two grey circles on this page each represent a rhythm. Go ahead and hover over them to play a rhythm one at a time. They don’t sound the same, do they?
Intuitively, we may know that they are different by picking up a few visual or aural cues. For example, the number and positioning of the circles are different for each rhythm, and the beats corresponding with the circles aren’t at the same place.
Parsing out these differences perhaps isn’t the most difficult task for us to do at a high level, so let’s break it down a bit more.
In a TedEd video, John Varney defines rhythm as “essentially an event repeating regularly over time”. But as the video explains, a uniform event over time doesn’t really lend itself to the more complex musical rhythms that we have on the right. Consider a simple cycle divided into 6 beats:
In order for us to get this strand to resemble our two musical rhythms, we have to assign stresses or accents to the beats and figure out when to place a beat. Try hovering over the two right rhythms again.
All we’ve really done is assign the strongest emphasis to the first beat and a weaker emphasis to the others. Delegating emphasis to beats within that six-beat cycle gives us the basic foundations of what we call time signature (top rhythm) and (bottom rhythm).
One of the easiest ways to differentiate the two is by counting.
For the 3/4 time signature, we can keep track of the cycle by repeating:
1 and 2 and 3 and
The “2” and “3″ represent the weaker beats (or commonly, upbeats) whereas
the “and”s allow us to subdivide the rhythm to better illustrate how we
are dividing the circle. In this case, we are splitting the cycle into three
groups of two.
Similarly, we can also break up the 6/8 rhythm into groups. When you hover over the bottom rhythm, our repeating phrase will be:
1 and ah 2 and ah
This rhythm lets us split the circle into two groups of three which elongates the phrasing a bit. This simple variance in partitioning the circle gave us an entirely different rhythm and feel. Neat, right?
Note that for 6/8, it is also common to count numerically from 1 to 6 (see alternative counting). For this type of counting, an emphasis on the first and fourth beat signifies a 6/8 time signature, whereas a strong emphasis on the first and weaker emphasis on the third and fifth beats signal 3/4.
The best way to get a feel for the two is to see -- or rather, hear -- them in action.
Both time signatures are common in songs you’ve probably heard. For this introduction however, we’ll be listening to Tchaikovsky’s Waltz of the Flowers for 3/4 and Mozart’s Piano Concerto No. 23 Mvmt. 2 for 6/8. Note that changes in tempo will speed up or slow down our rhythms.
The numbers are still up on our circles to help with counting. Go ahead and hover over the audio clips! See if you can hear differences in the phrasing of notes in the two cycles.
This was only an introductory, surface level exploration of the two rhythms, but there is a lot more to dive into, such as what the numbers in time signatures mean.
Hopefully, it helped improve intuition on how to differentiate and recognize the two at a basic level. However, there are many more nuances to the rhythms and many different kinds of rhythms to explore as well.
Don’t know where to start? I recommend taking a peek here for Khan Academy’s introductory series to rhythm in general.