It's safe to predict that very few people who hear this extraordinary performance of the greatest of all sets of variations for piano will have heard one quite like it before. Andreas Staier bases his performance on the autograph manuscript of the Diabelli Variations, which only became accessible when it was acquired by the Beethoven House in Bonn three years ago, and he plays it on a copy of a Conrad Graf instrument from Beethoven's time, one which includes the extra novelty features that were so popular with amateur pianists then. There's the "moderator" pedal, which mutes the sound, a bassoon stop which provides a reedy buzz, and the janissary stop, intended to imitate the percussion of the "Turkish music" so popular around the turn of the 19th century. Staier uses those extra tone colours discreetly, but also with huge imagination, producing an unearthly, almost mystical effect in the 20th variation, or underlining the successive parodies of Mozart's Don Giovanni and a Czerny study in the 22nd and 23rd.
Yet his performance is about much more than special effects. Staier's variations of touch and tone and the nuances of his pedalling would be remarkable on a modern concert grand, let alone such an early instrument, while he is always alert to the ways in which he can articulate and alter the pacing of what can seem a forbidding span of music. Some variations are separated by exaggerated pauses, while others run seamlessly into the next, while repeats are often subtlely varied. The result is the best kind of historically informed performance, one that makes you listen to a familiar work with fresh ears.
Staier's interventions aren't confined to Beethoven's work. He precedes it with 12 of the other variations on his waltz that the publisher Anton Diabelli commissioned from composers of the time. Most of them are undistinguished, but two stand out – a bravura treatment by the 13-year-old Liszt, and a touchingly simple one by Schubert. Staier links them to Beethoven's monumental set with a contribution of his own, a three-minute improvised introduction of the kind that early 19th-century pianists would have been expected to serve up as a matter of course.
