Using time signature [Light] [Beginner] [Professional] [Notation] [Composition Light] [Composition Pro] [Drums and Percussion] [Guitar] [Choir] [Keyboard] [Soloist]
We have learned that the measure is a way
to divide the duration of a musical work into smaller parts.
We gave many examples, speaking about a 4/4 measure, without
specifying what these two numbers mean.
Those numbers are called the time
signature. They determine the total duration of the rhythms
that can fit inside a measure. The first number (the numerator of the time
signature) indicates the number of beats the measure is
divided in. The second number (the denominator of the time signature) indicates the contents of
each beat.
The beat
is a division of the measure. In our preceding examples, we
often spoke about a beat as being equivalent to the quarter
note duration. This is only valid when the denominator of the
time signature is equal to 4 (it is by the way the more
common case).
The possible values for the denominator are
1,2,4,8,16 or 32. This value determines the content of one
beat in the measure. Here is the equivalence table:
The bold values are the most
common. The numerator of the time signature determines how
much of these beats will fit in one measure. In the examples
of the preceding lessons, the 4/4 thus represents a measure
made up of 4 quarter notes. In the same way, 6/8 is a measure
made up of 6 eighth notes, 2/2 is a measure made up of 2 half
notes, etc.
The time signature used is indicated in the
first measure, in the middle of the staff, just after the
clef and the possible key signature. This indication is valid
for all following measures. It is possible to change the time
signature in the middle of a music work or even each measure
if needed. In this case, the new time signature is displayed
and stays valid until the next change:

The first beat of a measure is a strong
beat. It marks the beginning of the measure. Other beats are
weak beats. Strong beats have a tendency to be more marked
than the others. They contribute to establish time reference
points in the course of music.
Composite time signature [Light] [Beginner] [Professional] [Notation] [Composition Light] [Composition Pro] [Drums and Percussion] [Guitar] [Choir] [Keyboard] [Soloist]
The numerator of a time signature can be
composed of several numbers separated by the "+"
sign. Here is an example:

This composite measure thus comprises 3+2 =
5 quarter notes. The idea of a composite time signature
modifies the distribution of weak beats and strong beats. If
a 5/4 time signature had been written, the contents would
have been the same, the first beat would have been strong and
the others weak. By writing 3+2/4, you indicate that a 3/4
measure alternates with a 2/4 measure. In this case, the
first and the fourth time are strong beats while the others
are weak. The performer reads and plays the notes as if the
measure was made up of 2 measures:

He will slightly and in a natural way
accentuate the first and the fourth beats, which are strong
ones.
Conventions and examples [Light] [Beginner] [Professional] [Notation] [Composition Light] [Composition Pro] [Drums and Percussion] [Guitar] [Choir] [Keyboard] [Soloist]
The 4/4 measure is often noted as a capital C meaning Common
Time. The 2/2 measure is often noted as a crossed C meaning Cut
Time. It is simply a notation convention. Here is an example:

Open and listen to the Ex023 example:

Remark:
some versions of Pizzicato cannot display composite measures.
This example may open in the professional evaluation mode. To go
back in the license mode, use the Options, Working
mode menu item.
The upper staff
marks the division of the beats in the measure. Check the
contents of each measure. Each time it fits the contents expected
by the time signature. The tempo is fixed at 60 quarter notes per
minute at the beginning of the first measure. It stays valid,
whatever the time signature.
Notice that the eighth notes in
the 6/8 measure were gathered by 3. It is very common for the
3/8, 6/8, 9/8 and 12/8 time signatures. Such measures are often
considered to be based on the dotted quarter note (3 eighth
notes). They respectively divide the measure into 1,2,3 and 4
dotted quarter notes. The eighth notes subdivide these dotted
quarter notes into 3 parts.