The new Music at Oxford season opened in typically adventurous fashion, with viol consort Fretwork presenting their unique version of Bach’s Goldberg Variations. Originally written for harpsichord, the Aria and its 30 variations have been transcribed for five viols by Fretwork co-founder Richard Boothby. Although Bach purists may raise an eyebrow at such an audacious move, the sound for much of the time was ravishing. Boothby has teased out the different strands of Bach’s music to highlight the contrapuntal nature of the variations, and the weaving together of those strands creates an almost ethereal effect. Only occasionally were there moments of uncertainty, as the weaving threatened to unravel and things became slightly disjointed.

According to one of Bach’s pupils, Johann Nicolaus Forkel, Bach wrote the variations for another of his pupils, Johann Gottlieb Goldberg, to play to the Russian Count Keyserlingk when in Leipzig, to help him sleep. It is easy to see how it could have that effect; the repetitious nature of the music is certainly soothing and calming enough to help the most chronic insomniac. Yet the exquisite sounds commanded the attention, and the audience seemed to have no difficulty in staying awake. That could also be something to do with the energy and virtuosity of Fretwork’s five musicians, whose masterly technique, sublime phrasing and sheer delight in what they were doing produced a performance that was utterly compelling.

There was also the fact that Boothby’s variations never settle too long with one player; just as the listener gets used to the sound of one viol taking the lead, with subtle accompaniment from different combinations of the other instruments, another takes over, creating constant interest as the treble, tenor and bass viols interact with each other in different ways. This was a musically and historically informed interpretation, delivered with eloquence and finesse, and with a touch of playfulness in the final variation, the lively Quodlibet. Wonderful.