Peter Walls


There has been considerable debate in recent years about the appropriate treatment of bass lines in Corelli Op. 5 and other duo and ensemble sonatas of the era. This article examines the relationship between continuo parts and separate bass parts in publications that include both. It argues that the case for accepting publication formats as a guide to performance practice is weaker than has often been claimed. The inadequacy of the standard terminology (particularly ‘trio sonata’) for Italian chamber-music ensembles in this period has been much commented on. Italian practice in the 17th century was to designate pieces a 2, a 3 etc. by the number of melodic lines disregarding any basso continuo part. Recent thinking about the implications of this for bass lines tends towards the general rule that if the description (a 2 etc.) does not specify a bass-register part then there is no call for more than one instrument to supply the continuo line. But this descriptive system does not work consistently. This article concentrates on sonata collections that include separate basso and basso continuo partbooks demonstrating that alongside sonatas that belong to clearly differentiated genres, we find examples of mixed genre. Even within individual sonatas the essential musical character may change from voce sola to a 2, or from a 2 to a 3.As the 17th century progressed such changes were less likely to be reflected in the provision made for instrumentalists in the part books. In other words, part books tended to reflect the maximum instrumentation required but would continue to supply what are essentially redundant melodic bass parts for sonatas that reduce to basso continuo. Such a situation argues against applying too rigidly a rule about banning a second bass line instrument from sonatas where the bass clearly has a (limited) continuo function.