The beat is the simplest manifestation of rhythm. It is added musical significance by various patterns of stress called meters.
Additional rhythmic interest result from the division of the beat into either :
Two equal part - Called Simple time
Three equal parts - Called Compound time.
The time signature (also known as meter signature) is a notational convention used musical notation to specify how many Beats are in each Measure and, which Note Value constitutes one beat.
The time signature appears at the beginning of the piece, as a time symbol or stacked numerals (for example: C or 3/4):
( C "common time" and 3/4 "three four time", respectively).
immediately following the Key Signature (or the Clef if the piece is in C major, A minor or modal subset).
A mid-score time signature, usually immediately following a Bar line,indicates a change of meter.
There are various types of time signatures, depending on whether the music follows simple rhythms or involves unusual shifting tempos, including:
|Simple||3/4 or 4/4|
|Compound||9/8 or 12/8|
|Complex||5/4 or 7/8|
|Mixed||5/8 - 3/8 - 6/8 - 3/4|
Simple time signatures consist of two numerals, one stacked above the other:
- the lower numeral indicates the note value which represents One Beat.
- the upper numeral indicates how many such beats there are in a Bar.
For example, 2/4 means two Quarter note (crotchet) beats.
3/8 means three Eighth note(quaver) beats.
The most common simple time signatures are 2/4 and 3/4 and 4/4
In compound meter, subdivisions of the main beat (the upper number) are split into three, not two, equal parts.
A Dotted note(half of it value longer than a regular note) becomes the beat unit.
Compound time signatures are named as if they were simple time signatures in which the one-third part of the beat unit is the beat, so the top number is commonly 6, 9 or 12 (multiples of 3).
The lower number is most commonly an 8 (an eighth-note): as in 9/8 or 12/8
3/4 - A simple signature, comprising three quarter notes. It has a basic feel of (Bold as a stressed beat):
6/8 Theoretically, this can be thought of as the same as the six-quaver form of 3/4 above with the only difference being that the eighth note is selected as the one-beat unit.
But whereas the six quavers in 3/4 had been in three groups of two.
6/8 is practically understood to mean that they are in two groups of three, with a two-in-a-bar feel (Bold as a stressed beat): one and a,two and a
Time signatures indicating two beats per bar, regardless it is simple or compound time are called Duple time. Those with three beats to the bar are Triple time.
Actual beat divisions. Let's look at 3/4 time, the actual beat division used can be the whole bar particularly in faster tempo.
Correspondingly in slow tempo the beat indicated by the time signature could in actual performance be divided into smaller units.
Meter or metre is a term that music has inherited from the Rhythmic element of poetry, where it means the number of lines in Averse, the number of syllables in each line and the arrangement of those syllables as long or short,
accented or unaccented. Hence it may also refer to the pattern of lines and accents in the verse of a hymn or ballad, for example, and so to the organization of Music into regularly recurring Measures or bars of stressed and unstressed "beats" by a Time Signature and bar-lines.