A new analysis of Beethoven's string quartets suggests that the composer's progressive deafness influenced the number of high notes he used in his music.

Researchers from the universities of Amsterdam and Maastricht looked at the op.18 quartets (1798–1800), written around the time when Beethoven was first experiencing hearing loss, the op.59 quartets (1806) and opp.74 & 95 quartets (1809–11), composed when his hearing impairment was worsening, and the late quartets opp.127–135 (1824–6), written when he was supposedly completely deaf.

For each quartet, the researchers calculated the percentage of notes above high G6 (1,586Hz) in the first violin part of the first movement exposition. Writing in the Christmas edition of the British Medical Journal, the researchers reported that the use of high notes decreased from 8 per cent for the op.18 quartets to around 5 per cent for the op.59 group and then to under 2 per cent for opp.74 & 95. But once Beethoven had gone totally deaf, the percentage of high notes increased, rising to just under 4 per cent in the opp.127–135 quartets.

Lead researcher Edoardo Saccenti wrote that, 'As his deafness progressed, Beethoven tended to use middle and low frequency notes which he could hear better when music was performed, seemingly seeking for an auditory feedback loop. When he came to rely completely on his inner ear he was no longer compelled to produce music he could actually hear when performed and slowly returned to his inner musical world and earlier composing experiences.'

He warned, however, that his team's findings are far from being conclusive: 'Proving or disproving whether Beethoven's hearing loss had a substantial impact on shaping his musical style would require complete and exhaustive statistical and spectral analyses of the composer's complete catalogue.'