Time Signatures in Musical Notation

In a Time Signature, the top number gives you the number of beats per measure and the bottom number gives you the type of note that takes the beat. The Time Signature is placed at the begining of the music right after the key signature. The Time Signature is not repeated at the begining of each system. It is only repeated if the Time Signature changes.

Time is perceived in music when a sequence of sounds are held for specific durations. The various note durations combined in harmonic and melodic form is called rhythm. More specific, rhythm is the combination of various measurements of time that shape melody, harmony, phrases and the whole composition.

For most music, the two ingredients that affect rhythm are tempo and metre. Metre is a measurement of music in time where time is divided into groups of pulses as designated by the top number of a time signature. Tempo tells you how fast the music is to be played.

The time signature defines the metre in music. The top number, given in simple time, may be in duple, triple or quadruple time. Simple time may also be combined with each other to form other complex metres.

The bottom number, common to all time signatures, tells you what note gets the pulse.