Time in the context of music theory means the grouping of a defined, in principle either even or odd number of beats in a unit of time, which since the 17th century has been marked visually by a bar line. It is very closely connected with rhythm, providing the stable basic framework for its individual elaboration, and comprises at least one up-beat and one down-beat (Metrics). The grouping of beats in a bar thus forms a central element of division and structure in the progression …