What we have learnt in the previous post was that time signature indicates the amount and value of the beats (crotchet, minim etc.) inside a bar in a piece of music. Time signature does not give us any information about the speed of the beats movement which is the tempo. The speed of the regular beat in a composition is called tempo.
Usually tempo can be denoted in a piece of music in two different ways.
- By approximate Italian terms which are shown in the picture below
- By precise metronome mark
Metronome is a device invented by Johann Maelzel in 1815 which produces regular, metric ticks like a clock and can be adjusted to tick at any speed.
At the start of the music the metronome marking includes a note value = number of beats per minute (Q = 60), this means that there are 60 crotchet beats per minute. Sometime the abbreviation M.M. (Maelzel’s Metronome) is added before the number.
Tempo often changes in a piece of music. These changes usually are shown by terms such as ritardando (gradually slow down), accelerando (gradually speed up), and a tempo (return to the original speed). There are also changes which are not usually indicated in the piece of the music and performers usually make them for expressive purposes.