The significance of violinist and Imperial Kapellmeister Johann Heinrich Schmelzer (1623 – 1680) has since been overshadowed by Biber, but in his day he was one of the most famous violinists in Europe and the favourite musician of the Holy Roman Emperor Leopold I, who reigned between 1658 and 1705. Thus the name of Australian violinist and musicologist David Irving’s charming new recording of Schmelzer’s Sonatae Unarum Fidium on Obsidian, The Emperor’s Fiddler.

Schmelzer’s sextet of sonatas, which was dedicated to Cardinal Carlo Carafa (solidifying new political alliances) puns on the double meaning of Fides – it can mean “one fiddle” or “unified faith”. Indeed, there is an ecclesiastical air to these works, written in...