Rhythm in music theory  can be defined as the pattern of sounds and silences in music that establishes the tempo and beat.

 TIME SIGNATURES


A time sginature is made up of two numbers  :-   top number and bottom number.


The top number  repesents the  number of beats in a bar 


The bottom number  represents the type of beat  (duration)


TYPES OF DURATION


4 at the bottom represents crotchet beats

2 at the bottom represents minim beats

8 at the bottom represents  quaver beats

16 at the bottom represents  semiquavers beats 


      

SIMPLE and COMPOUND Rhythms

 

For SIMPLE  Rhythms  each beat can be divided by TWO

Example : a crotchet / 2 =  2 quavers


For COMPOUND  Rhythms each beat can be divided by THREE

Example a dotted crotchet  / 3 = 3 quavers


TRIPLETS  are commonly used in Simple time

Example  : 3 quavers  (triplet)   represents  2 quavers  (in rhythm)


DUPLET  are commonly used in compound time

Example :  2 quavers  (duplet) represents  3 quavers  (in rhythm)



UNDERSTANDING DURATION / METRE


DURATION


You can have notes that are long or short in duration. 

Duration is the length of time each note is played for.


When you combine notes of different durations, you can create a rhythm.


BASIC RHYTHMS

 
Semibreve 4 beats (hold for 4 beats)
Minim 2 Beats (hold for 2 beats)
Crotchet 1 beat (hold for one beat)


A crotchet can be broken down into smaller divisions.
Semiquaver (1/4 beat)
Demisemi quaver (1/8 beat)


Quaver (1/2 beat)


DOTS IN RHYTHM


A dot after a note extends the note by half.
Example a dotted crotchet is equal to 1 and 1/2 beats.

METRE


Each piece of music is made up of a series of bars. Each bar contains a number of beats set by the time signature at the start of each piece.


TIME SIGNATURE


Each time signature has two numbers , top and bottom. The top number tells you how many beats to play in each bar. The bottom number tells you the type of beat required.

Top numbers (beats per bar,) can be
2,3,4,5,6,7,8,9,12,16

Bottom numbers (types of beat)

4 at the bottom - crotchet beats
8 at the bottom - quaver beats
2 at the bottom - minim beats
16 at the bottom - semiquaver beats


GROUPING OF MUSICAL NOTES


Notes are written in music in set groups according to the time signature.


Groups of notes are written in music separated by bar lines.

REGULAR TIME DIVISION EXAMPLE


                   2
                  4


2/4 means two crotchet beats in a bar.
The bar can be divided equally (1+1). Rhythm must be grouped within beats, one set of notes for the first crotchet beat and a further set of notes for the second crotchet beat.

Further regular time signatures

4.  6.  12.   2.   4. 
4.  8.   8.    2.   2. 
 

IRREGULAR TIME DIVISION EXAMPLE 


                 3
                4


3/4 means three crotchet beats in a bar. The bar cannot be divided equally. Therefore the bar needs to be split into either 2+1 or 1+2. Rhythm must be grouped within beats. For this example , I e set of notes grouped under two beats, a further set of notes grouped under one beat.

Further irregular time signatures

3.    9.    3.
4.    8.    8.


RESTS IN MUSIC


Music rhythms are made up of a series of sounds (notes) and silences (rests).


each note rhythm has an equivalent rest rhythm.

Grouping of notes and rests follow the same rules. It's important to understand the time signature and how notes / rests are grouped within each bar (regular or irregular).