When one thinks of the ‘X factor’, it’s fairly certain that the first image that comes to mind is not that of a quiet, unassuming man in his mid-sixties, clad in evening dress. But Simon Cowell is missing a trick: even without the sparkling trappings of show-biz, pianist John Lill is steeped in the ‘X factor’, that indefinable ingredient which separates the very good performers from the magical ones. St Paul’s School’s Wathen Hall was the ideal venue for this lesson in musical magic, combining the intimacy of a small venue with the advantages of a pleasant acoustic and superb piano.

Lill took to the stage with a characteristic lack of fuss, launching straight away into Mozart’s luminous Sonata in F major, K332. His glowing account served to partly elucidate the mystery of the elusive ‘X factor’: in his hands, the well-known sonata felt fresh, as though Lill had composed the piece in his dressing room prior to arriving on stage. This magical effect was further heightened by his enraptured audience; the ability to hold the attention of his audience throughout an entire sonata is another component of Lill’s superb artistry.

Schumann’s Faschingsschwank aus Wien followed the light-hearted cheek of Mozart’s finale, allowing Lill to revel in a very different range of emotions. His ability to switch instantly from the clarity of the Mozart sonata to the Romantic drama of Schumann’s five-movement portrait of Vienna’s Carnival demonstrated yet another facet of the Lill artistry, this ability to produce completely different sounds from the same instrument, so that one might swear that a different pianist performed the two works. This ability to play absolutely in style was further demonstrated by the last work in the first half, Prokofiev’s Toccata, where Lill’s dispassionate delivery of the showpiece emphasised the machine-like nature of the repeated toccata figure.

Brahms’s Three Intermezzi, Op. 117 returned to the world of the Mozart sonata, a gently glowing performance which held the audience captive. Lill’s superlative musicality brought a huge range of colour to these beautiful miniatures, carefully balancing every line in the texture until the piano began to take on the sounds of a group of singers.

In the final piece of the programme, Beethoven’s Sonata no. 23, ‘Appassionata’, this chamber choir grew into a full orchestra. The piece demands a huge amount from the pianist, putting both lyrical and dramatic playing to the test. The first movement is particularly challenging, requiring a clearly thought-out structure from the performer in order to prevent the contrasting sections from sounding disparate. Lill dealt with this very effectively by creating reference points for the audience, stressing certain phrases in order to keep them in mind when they reappear in other sections. Lill chose a brisk tempo, which felt slightly rushed in places, not allowing himself the time to work the same magic as he achieved in the Mozart. The opposite was true in the Andante con moto second movement: Lill’s flowing tempo brought out the simple beauty of the theme and variations without becoming bogged down in detail. An earth-shattering Presto ended the Sonata, reminding us of the formidable technical ability on which Lill has built his artistry. Recommended viewing for all X Factor hopefuls perhaps?