Editing Conducting (section)

===Beat and tempo===
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At the beginning of a piece of music, the conductor raises their hands (or hand if they only use a single hand) to indicate that the piece is about to begin. This is a signal for the orchestra members to ready their instruments to be played or for the choristers to be ready and watching. The conductor then looks at the different sections of the orchestra (winds, strings, etc.) or choir to ensure that all the orchestra members are ready to play and choir members are ready. In some choral works, the conductor may signal to a pianist or organist to play a note or chord so that the choir members can determine their starting notes. Then the conductor gives one or more preparatory beats to commence the music. The preparatory beat before the orchestra or choir begins is the [[Beat (music)#Downbeat and upbeat|upbeat]]. The [[Beat (music)|beat]] of the music is typically indicated with the conductor's right hand, with or without a baton. The hand traces a shape in the air in every [[bar (music)|bar]] (measure) depending on the [[time signature]], indicating each beat with a change from downward to upward motion.<ref>{{Cite news|title=The Maestro's Mojo – Breaking Conductors' Down by Gesture and Body Part|first=Daniel J.|last=Wakin|date=6 April 2012|access-date=26 April 2012|url=https://www.nytimes.com/2012/04/08/arts/music/breaking-conductors-down-by-gesture-and-body-part.html|newspaper=[[The New York Times]]}}</ref><ref>{{Cite book|last=Farberman|first=Harold|author-link=Harold Farberman|url=https://books.google.com/books?id=5W-z-wtm9fgC&pg=PA42|title=The Art of Conducting Technique: A New Perspective|date=1999-11-27|publisher=Alfred Music|isbn=978-1-4574-6032-6}}</ref>

The [[Beat (music)#Downbeat|downbeat]] indicates the first beat of the bar, and the upbeat indicates the beat before the first note of the piece and the last beat of the bar. The instant at which the beat occurs is called the ''[[Wikt:ictus|ictus]]'' (plural: ''{{lang|la|ictūs}}'' or ''ictuses'') and is usually indicated by a sudden (though not necessarily large) click of the wrist or change in baton direction. In some instances, "ictus" is also used to refer to a horizontal plane in which all the ictuses are physically located, such as the top of a [[music stand]] where a baton is tapped at each ictus. The gesture leading up to the ictus is called the "preparation", and the continuous flow of steady beats is called the "{{lang|de|takt}}" (the German word for bar, measure and beat).

If the tempo is slow or slowing, or if the time signature is [[Metre (music)#Compound metre|compound]], a conductor will sometimes indicate "subdivisions" of the beats. The conductor can do this by adding a smaller movement in the same direction as the movement for the beat that it belongs to.<!---I can't find the words to make this more clear right now, but I don't think this is clear or understandable to the layman yet---not just quadruple metre--->

Changes to the tempo are indicated by changing the speed of the beat. To carry out and to control a [[rallentando]] (slowing down the pace of the music), a conductor may introduce beat subdivisions. While some conductors use both hands to indicate the beat, with the left hand mirroring the right, formal education discourages such an approach. The second hand can be used for [[Cue note|cueing]] the entrances of individual players or sections and to aid indications of dynamics, phrasing, expression, and other elements.

During an instrumental solo section (or, in an opera orchestra during a vocalist's unaccompanied solo), some conductors stop counting out all the subdivisions and simply tap the baton down once per bar, to aid performers who are counting bars of rests.

There is a difference between the "textbook" definition of where the ictus of a downbeat occurs and the actual [[Historically informed performance|performance practice]] in professional orchestras. With an abrupt, loud [[Dynamics (music)#Sudden changes and accented notes|sforzando]] chord, a professional orchestra will often play slightly ''after'' the striking of the ictus point of the baton stroke.