Rhythmic Notation; Time Signatures - E-Mu PX-7 Owner's Manual

Rhythmic
Notation
Measures
Note values
Triplets
Time
Signatures
This extremely brief overview is intended solely as a refresher and memory
jogger; for a detailed description of rhythmic notation, see any good book
on music theory.
A piece of music is divided into measures, and each measure is divided into
notes. The number of notes, and rhythmic value of the notes, depends both
on the composition and the time signature (see Appendix C).
With a measure written in 4/4, there are four beats per measure, with each
beat representing a quarter note. Thus, there are four quarter notes per
measure of 4/4 music.
There are two eighth notes per quarter note. Thus, there are eight eighth
notes per measure of 4/4 music.
There are four sixteenth notes per quarter note. Thus, there are sixteen
sixteenth notes per measure of 4/4 music.
There are eight thirty-second notes per quarter note. Thus, there are thirty-
two thirty second notes per measure of 4/4 music.
There are also notes which span a greater number of beats than quarter
notes. A half-note equals two quarter notes. Therefore, there are two half-
notes per measure of 4/4 music. A whole note equals four quarter notes.
Therefore, there is one whole note per measure of 4/4 music.
The above notes divide measures by factors of 2. However, there are some
cases where you want to divide a beat into thirds, giving three notes per
beat. Dividing a quarter note by three results in eighth note triplets. The
reason why we use the term "eighth note triplets" is because the eighth
note is closest to the rhythmic value which we want. Dividing an eighth
note by three results in sixteenth note triplets. Dividing a sixteenth note by
three results in thirty-second note triplets.
A time signature (also called metric signature) describes the meter of a piece
of music. It consists of two numbers arranged like a fraction, such as 3/4, 4/
4, etc. The top number (numerator) indicates the number of beats in each
measure, while the bottom number (denominator) indicates the rhythmic
value of each beat. For example, with a 3/4 time signature the numerator
indicates that there are three notes per measure, while the denominator
indicates that each of these notes is a quarter note. 4/4 indicates that each
measure includes 4 quarter notes. Usually the downbeat (1st beat) of each
measure is emphasized by a metronome to help you get a feel for the meter.
3/4 and 4/4 are the most common time signatures, but they are by no
means the only ones. In jazz, both 5/4 (where each measure has five 1/4
notes) and 7/4 (where each measure has seven 1/4 notes) are often used. In
practice, complex time signatures are played like a combination of simpler
time signatures; for example, some 7/4 compositions would have you count
each measure not as "1, 2, 3, 4, 5, 6, 7" but as "1, 2, 3, 4, 1, 2, 3". It's often
easier for musicians to think of 7/4 as one bar of 4/4 and one bar of 3/4,
since as we mentioned, 4/4 and 3/4 are extremely common time signatures.
Appendix

Rhythmic Notation

PX-7 Owners Manual 339