Bach’s forty-eight Preludes and Fugues, like most keyboard works of the Baroque, were written for domestic and private use rather than public performance. It is even likely their purpose was didactic. Often known as the “Old Testament” of the keyboard, (the “New Testament”, comprising Beethoven’s thirty-two sonatas), such music probably would not have been played in public until perhaps up to a hundred years after its composition. Yet in more recent times it has become fashionable to present the compendium of keyboard technique that makes up the “forty-eight” as a cycle of performances over several days. Of course, they represent a hugely varied collection, but to hear them from the first to the last item is not in any way a culminative experience.

Over the course of four days this week at the Hay Festival, the Austrailian-Welsh pianist Daniel Martyn Lewis is presenting the whole cycle in the austere surroundings of the Catholic Church of St Mary. In fact, this is far from being his first presentation of the cycle, which he previously gave at the Hay Festival as long ago as 2002. Over the years, Bach has become a central preoccupation for Lewis. But in terms of the huge stylistic range of performances of Bach, where do his own performances sit? On Monday, the opening night, he unashamedly used the resources of a modern full-size Steinway D; initially it seemed that his view of Bach might be filtered back from the perspective of the nineteenth century. As the journey through the first twelve Preludes and Fugues progressed though, it became obvious that this was a much more individual and idiosyncratic view of Bach.

The performances are far removed from, say, the rolling paragraphs of Edwin Fischer’s Bach (the first pianist to record the “forty-eight”), the razor-sharp contrasts of Glenn Gould or the clear-cut lines of Andras Schiff. Instead, Lewis brought out the angularity of this music, emphasising and bringing out individual contrapuntal lines. In the hands of some performers Bach’s rhythms can seem rather square, but here there was a freedom of response which, if rather wild at times, was never dull.

Overall the preludes seem to engage his imagination rather more than the fugues: spacious and uncluttered in the famous opening C major prelude, understated with filigree ornamentation in the E flat minor, brisk and unsentimental in the E major, flowing and unfussy in the C sharp minor; each prelude took on a new sound world of its own.

Playing to a capacity audience, Lewis, on the opening night, played through the first twelve Preludes and Fugues. It says much for his playing that he maintained a rapt attention throughout an hour’s playing without an interval.