John Paul Ito

Nascent Hypermeter in Bach: The Development of Style and Perception

Hearing hypermeter in real time involves hearing in terms of a set of well-known possibilities, or schemas.  But how did these schemas develop?  Did composers imagine hypermeter and then write regular music so that others might hear it too?  Or could hypermeter be an emergent property of statistical regularities that exist for other reasons?
This paper investigates these questions, looking at Bach’s music as a test case, placed as it is between the norms of the 17th century (compound meter, irregular phrase lengths, relatively low salience of bar lines in compound meter, few indications of hypermeter) and those of the 19th (salient notated downbeats, robust hypermeter, standard hypermetrical manipulations).

Two hypotheses are tested, using a corpus of ritornello movements.  First, the notated measure was being stabilized.  In a variety of meters, some simple and some compound, the metrical placement of ritornello returns and of cadences suggests an intermediate stage in which half-bar displacements are more prevalent than in later music, but in which they are not arbitrary, rather reflecting hierarchies of key and of form.  Second, four-bar construction of ritornellos has a prevalence that far exceeds chance.  There are furthermore signs that Bach intended hypermetrical hearing, as ritornellos with a multiple of four bars are often followed by episodes starting on the subsequent measure, while ritornellos that contain one additional bar beyond a multiple of four often end with a phrase overlap, the cadence of the ritornello coinciding with the beginning of the episode.
Statistical evidence for hypermeter in Bach must be balanced, however, by consideration of examples in which a regular four-bar frame receives an internal organization that would seem to render the frame unhearable.  Such examples suggest: that hypermetrical hearing was for Bach only one of the possible results of four-bar construction; and that listeners should expect the unexpected.