Zerreisset, zersprenget, zertrümmert die Gruft is a serenata for the nameday of Leipzig University’s popular law and philosophy teacher August Friedrich Müller, first performed (perhaps outdoors by torchlight) on August 3, 1725. A chorus of winds complain at being cooped up during the summer months. Aeolus releases them and gleefully anticipates the havoc they will cause (the god of the winds is sung playfully by Roderick Williams). Zephyrus (god of evening breezes), Pomona (goddess of fruit trees) and Pallas (goddess of wisdom) eventually persuade Aeolus to relent and command the winds to be calm when they inform him it is Müller’s nameday. This civilised nonsense involves the largest range of instrumentation Bach ever used in a single work: three trumpets, timpani, two horns, two flutes, two oboes, oboe d’amore and strings (including concertante viola d’amore and viola da gamba in Zephyrus’s conciliatory ‘Frische schatten, meine Freude’). Bach Collegium Japan’s trumpets and horns mount a thrilling assault to play without modern drilled holes to fix their intonation to the expectations of modern ears, although the experiment stretches to the furthest edges of acceptable tuning in the bookend choruses. A virtuoso high violin and Joanne Lunn’s voice intertwine prettily in Pallas’s mildly suggestive ‘Angenehmer Zephyrus’.

Vereinigte Zwietracht der wechselden Saiten celebrates the university’s appointment of Professor Gottlieb Kortte (who gave his inaugural address on December 11, 1726). The allegorical libretto (hardly a dramma per musica) presents Industry, Honour, Happiness and Gratitude taking turns to pay compliments to Leipzig’s newest don. The outstanding moment is Gratitude’s ‘Ätzet dieses Angedenken’, in which Robin Blaze’s gentle singing is accompanied by a lyrical pair of flutes with some softly repetitive interjections from unison upper strings that illustrate a hammer chipping away at marble.