Prom 33: King's Consort / King, Royal Albert Hall, London <!-- none onestar twostar threestar fivestar -->

Haydn and Mozart - two anniversaries, one of death, one of birth - were celebrated by The King's Consort and King's Choir under their director, Robert King, with a fine all-British line-up of vocal soloists. But it was not the "right" Haydn.

Michael Haydn had the misfortune to be born five years after his illustrious brother and has been virtually written out of the history books. He lived from 1737 to 1806, hence the anniversary. How might it have been if he had been the "right" Haydn? Judging by his Requiem for Archbishop Sigismund, which he composed in 1771, M Haydn's future might have been bright.

The key - C minor - is dark and its opening pre-echoes fascinatingly a Mass by his brother Joseph written much later: the Nelson Mass. Perhaps it is the colouring - period trumpets, horns, trombones and timpani - that sets the sombre and stately tone. But Michael appears to have made miscalculations. The mezzo-soprano Hilary Summers has the lowest of ranges, her sound at times manly, but even she had difficulty being heard at some of these pitches. In the "Sanctus", where the mezzo leads with the tenor (James Gilchrist) and bass (Peter Harvey), her low notes could not carry. The soprano Carolyn Sampson duetted touchingly with Summers in the final "Requiem", but it was the "Et lux perpetua luceat eis" that whetted the appetite for more M Haydn.

This work was receiving its Prom premiere, not just for its sake one suspects, but to show how clearly Mozart knew this work. Imitation is the sincerest form of flattery and Mozart was a close friend, sometimes lending M Haydn a hand (compositionally) when time ran out. Anyone who knows Mozart's Requiem will spot many similarities.

It was not Mozart's Requiem we heard but his "Coronation" Mass, written eight years after the Haydn. Also a Salzburg setting, it at once revealed the shortcomings of Haydn. How astonishing was Mozart's grasp of structure and drama, even if Joseph II had decreed that no mass should last more than 45 minutes.

BBC Proms to 9 September (020-7589 8212; www.bbc.co.uk/proms)