Beat (music)

A beat is a pulse on the beat level, the metric level at which pulses are heard as the basic unit. Thus a beat is the basic time unit of a piece; for every tick on a metronome, each tick is a beat. Depending on the context, beat may denote either:


 * the onset of the corresponding time unit, a point in time, the very moment when the metronome ticks, or


 * the complete time interval between two consecutive taps, so to say, or


 * in popular music, the whole sequence of individual beats (in the sense of meter, rhythm, Groove, or riddim).

Most music is characterised by a sequence of stressed and unstressed beats (often called 'strong' and 'weak') organised into a meter and partially indicated by a time signature, the speed of which is determined by a tempo. In the context of a time signature, the term 'beat' most often refers to the bottom number &mdash; so in 3/4, most people would consider the beat to be the 4; that is, a quarter-note, or crotchet. Musicians typically find that mentally counting a regular series of beats enables them to keep synchronised even if the music is not characterised by regular rhythm. Metric levels faster than the beat level are division levels, and slower levels are multiple levels.

A hyperbeat is one unit of hypermeter, generally a measure, as is to a hypermeasure what a beat is to a measure.(Stein 2005, p.329)

Upbeat
An Upbeat is an unaccented beat or beats that occur before the first beat of a following measure. This is also called anacrusis. In other words, this is an impulse in a measured rhythm that immediately precedes, and hence anticipates, the downbeat, which is the strongest of such impulses. It is also not only this, but also can be the last beat in a normal 4/4 bar where that bar precedes a new bar of music.

It is also an anticipatory note or succession of notes occurring before the first barline of a piece, sometimes referred to as an 'upbeat figure', section or phrase. An alternative expression for 'upbeat figure' is 'anacrusis' (from Greek. ana: 'up towards' and krousis:  'to strike'; Fr. anacrouse). This term was borrowed from poetry where it refers to one or more unstressed extrametrical syllables at the beginning of a line.

Downbeat
Downbeat is the impulse that occurs at the beginning of a bar in measured music. In music performance and music theory, the 'downbeat' is the first beat of a measure in music. It is named after the downward stroke of the director or conductor's baton at the start of each measure. This differentiates it from the back beat on the even beats. Downbeat can be found in most funk music, with heavy emphasis 'on the one' (the first beat of every measure), to etch a distinctive sound, rather than the backbeat, familiar to many R&B musicians, that placed the emphasis on the second beat.

Back beat
In music a back beat (also called the backbeat) is a term applied to the beats 2 and 4 in a 4/4 bar or a 12/8 bar, as opposed to the odd downbeat, (quarter beat 1). That is, counting out a simple 4/4 rhythm, 1 2 3 4, the 1 beat is the down beat. If beat 4 immediately precedes a new bar it is also called an upbeat (see upbeat article for more information on what an upbeat is). The up and down refer to movements of the conductor's baton.

Afterbeat refers to a percussion style where a strong accent is sounded on the second, third and fourth beats of the bar, following the downbeat.

The effect can be easily simulated by repeatedly counting to four while alternating strong and weak beats:


 * 1 2 3 4 1 2 3 4 -- backbeat emphasis (and in 4/4 if beat 4 immediately precedes a new musical bar then beat 4 is also an upbeat)
 * 1 2 3 4 1 2 3 4 -- downbeat emphasis (and in 4/4 if beat 4 immediately precedes a new musical bar then beat 4 is also an upbeat)
 * 1 2 3 4 1  2 3 4 -- Afterbeat emphasis (and in 4/4 if beat 4 immediately precedes a new musical bar then beat 4 is also an upbeat)

The style emerged in the late 1940s in rhythm and blues recordings, and is one of the defining characteristics of rock and roll and is used in virtually all contemporary popular music, bossa nova being a notable exception.

Off-beat
The Off-beat is a musical term commonly applied to rhythms that emphasize the weak beats of a bar. According to Grove Music, the 'Offbeat' is [often] where the downbeat is replaced by a rest or is tied over from the preceding bar'. The downbeat can never be the off-beat because it is the strongest beat in 4/4 time.

In music that progresses regularly in 4/4 time, the first beat of the bar is the strongest, the third is the next strongest, and the second and fourth are weaker; subdivisions (like eighth notes) of any of the beats are weaker than the main beats and if used frequently in a rhythm can make it off-beat.