‘You have to give yourself over to this painful journey’

Inside a café in Soho, London, a sidestep away from Ronnie Scott’s jazz club, Rachel Podger is sliding her precious 1739 Pesarinius violin out of its case. Podger has just recorded the complete Rosary (or Mystery) Sonatas by the Baroque composer Heinrich Ignaz Franz von Biber and we’re talking about the physical demands that the piece made on her instrument – and Podger wants to show me her tailgut.  

Biber’s Rosary Sonatas remain a riddle wrapped inside a whole cluster of technical enigmas. On paper, you might well assume that the composer’s instructions on how to perform his cycle of devotional pieces represents the hare-brained scheme of a particularly outré associate of the post-war avant garde. Scordatura – the art of intentionally retuning strings away from the customary configuration – has the effect of twisting the acoustic reality of the violin against itself. Mahler, in the second movement of his Fourth Symphony, asks for the lead violinist to tune their violin up a whole tone to thin the sound and lend the instrument ghoulish distance. But that is nothing compared to Biber’s grand schema: a cycle of 16 works in which scordatura tunings become increasingly complex, knotty and cryptic, until in the 11th sonata, ‘The Resurrection’, where Biber asks for the two inner strings on the violin to be crossed – the lower string now carrying the higher voice as the natural order of voices is reversed, the violinistic equivalent of running the wrong way up an escalator.