Types of time signatures

There are different types of time signatures, which can indicate various and complex meters.

Note

Dorico Pro uses the definitions for meters commonly used in American English. These definitions, such as which meters are considered simple and compound, might be different in other languages.

Simple

In simple time signatures, each beat is divided by two into equal groups of notes. Simple time signatures can be simple duple, such as 2/4, simple triple, such as 3/4, or simple quadruple, such as 4/4.

Compound

In compound time signatures, each beat is divided by three into equal groups of dotted notes, such as 6/8, which contains two dotted quarter note beats, or 9/4, which contains three dotted half note beats.

Irregular

Irregular time signatures, such as 5/4 or 7/8, cannot be subdivided into equal beat groups. Because the numerator is odd, these time signatures must be divided into unequal beat groups. For example, 5/4 usually contains a half note beat and a dotted half note beat.

Additive

Additive time signatures show how bars are subdivided into beat groups. You can show beat group numerators for any type of time signature. For example, instead of 7/8, you could show an additive time signature of 2+3+2/8.

Alternating

An alternating time signature indicates a regular pattern that switches every bar between two or more time signatures, in the indicated order. For example, for a phrase with twelve eighth notes that needs to be emphasized 3+3+2+2+2, an alternating time signature of 6/8+3/4 might allow the two meters to be read more clearly.

Interchangeable

An interchangeable time signature indicates a set of time signatures at the start of the piece that can be used during the piece, such as 3/4–2/4. Unlike alternating time signatures, interchangeable time signatures do not require a fixed pattern; any bar in the piece can follow any of the time signatures in the set without having to restate the time signature.

Note

You must manually input the appropriate time signatures where you want them, as unlike alternating time signatures, there is no fixed pattern for them. Any time signatures you input after an interchangeable time signature that are specified in it are hidden automatically until you end the interchangeable time signature.

They can have different separator styles in Dorico Pro, which you can set project-wide and also change individually.

Aggregate

An aggregate time signature shows two or more meters within the same bar, such as 2/4+3/8+5/4. Dorico Pro automatically shows dashed barlines to indicate the divisions between the different meters, but you can also specify that you do not want to show dashed barlines when you input aggregate time signatures with the popover.

Open

An open time signature has no restrictions on meter, beaming, or beats. Any number of notes can be added, with any beaming. For example, open time signatures might be used for cadenza passages.

Note

In open meters, you must input barlines manually.

Non-power of two

A non-power of two time signature is one such as 5/6, which indicates five sextuplet quarter notes (crotchets) where the sextuplet overall equals a whole note (semibreve). Examples of time signatures like this can be found in the music of Adès.

Note

Some composers, such as Boulez, have written fractional time signatures. Dorico Pro does not currently support fractional time signatures.