Groups of Two Eighth Notes
The top number of a time signature can be anything. A "3" in this position would indicate three counts per measure, a "17" as the top number would mean that there are seventeen counts per measure, and "6.75" would indicate six and three-quarters counts per measure. Yes, although it is very rare, the upper number does not have to be a whole number. It can really be anything -- whole, fractional, or whatever.
The lower number of a time signature is a different matter. It can only be one of the following: 1, 2, 4, 8, 16, 32, etc. (powers of two). This is a type of code that stands for a particular note value. A "1" in this position would indicate a whole note, 2 means a half note, 4 means a quarter note, 8 means an eighth note, 16 means a sixteenth note, and 32 means a thirty-second note. Now that we know what the bottom number stands for, what does it mean? The bottom number tells you which note value (quarter, eighth, half, etc.) is equal to one of the counts in the measure.
Here are some examples. In 4/4 meter, there are four counts per measure, and the quarter note is the note value that equals one of the counts. In other words, the time value of a measure is equal to four quarter notes. In 6/8 meter, there will be six counts in every measure, and the value of one of those counts is the eighth note. In other words, each measure will have the time value of six eighth notes. 5/2 meter has the value of five half notes in each bar while a time signature of 3/16 would contain the value of three sixteenth notes in every measure.
If you are getting a little confused about these 3/16 meters, don't worry. I just wanted you to know the reason why there are four counts in each measure of the exercise, and why we use the counting system of 1, 2, 3, 4 to keep track of them. Remember, that each measure doesn't have to have only quarter notes. Each measure only has to contain the value of four quarter notes. This lesson will be dealing with other ways to notate the value of a quarter note.
The new figure for this WebRhythm lesson is a group of two eighth notes. A single eighth note is exactly 1/2 the value of a quarter note. In other words, if a quarter note equals one second of time, then a single eighth would equal 1/2 second of time. If a quarter note equaled one inch, then an eighth note would be 1/2 inch. If a quarter note had the value of a dollar bill, then an eighth note would have the value of a 50¢ piece. The reason that I'm making all of these analogies to stress the point that an eighth note is always equal to half the value of a quarter note, no matter what the quarter note's duration or length happens to be. Using these analogies, you can see that two eighth notes will always equal one quarter note (1/2 + 1/2 = 1).
A single eighth note is written as a note-head with a stem and a single flag.
Two or more eighth notes can be grouped together with a beam. In these cases, the beam replaces the flag. Why might a composer choose to beam eighth notes together rather than use flags? In most cases, eighth notes are beamed together to show the musician how the notes are grouped together into counts. Music is easier to read when counts are grouped together.
If eighth notes divide each quarter note in half, and quarter notes are counted "1, 2, 3, 4", we'll need to have some way to count the divisions of the quarter. We will be using the syllable "and" to do this.
In order to see how this works, go take a brisk walk. As you are walking, count the numbers "1, 2, 3, 4" every time your right foot hits the ground. Every time your left foot touches down, say the word "and". If you are walking at a steady pace (tempo), then you will see the relationship between the quarter notes and the eighth notes.
Before you attempt to play the following
exercise, listen to the "bronze" level audio file. As you
count the numbers "1, 2, 3, 4" to the beat of the metronome
(the cowbell sound), you'll hear the 8th note rhythms played twice as
fast -- "1 AND 2, 3, 4". Once you
can count the first few measures out loud with the audio file, then
you're ready to play along!
In performing this exercise, be certain to keep the speed of the number counts even. Also pay close attention to the fact that you want the "and" counts to split the number counts exactly in half. The more accurately you make your counts, the more solid your playing will become. This lesson's exercise mixes the pattern of two eighth notes with the quarter note and the quarter rest from the last article. Remember to play on the beat if you see a quarter note, don't play on the beat if you see a quarter rest, and play the beat and the "and" when you see a group of two eighths.
It might also be a
good time to review the helpful hints that we talked about in the last