Feathered beams

In music, durations are quantized to subdivisions of time in the form of fractions of the inverse powers of 2 (e.g., 1/2 0 , 1/2 1 , 1/2 2 , etc.). All durations that are not involved in tuplets can be represented by sums of these fractions. The gradual transition from one note duration to another through a specified number of intermediate note values requires an accelerando/ritardando beam (i.e., feathered beam). This notation, however, does not indicate exactly how the gradual transition through the intermediate note values is to occur. The various details may be so contradictory that feathered beams may be impossible to realize. Thus, the notation is inherently indeterminate, although it is not often regarded as such. This paper examines these concepts and combines rhythmic nomenclature with a graphing system to deconstruct feathered beams using examples from George Crumb's Night Music I.