The highlight of the year, for a small singing group I belong to, is an evening’s work with a conductor who specialises in 16th-century music. We practise hard in advance. Our repertoire is English and Italian madrigals, and this year we had two by Monteverdi but were divided over which English one to choose. We sight-read a massive six-voice piece by Thomas Weelkes, ‘Thule, the Period of Cosmographie’, with its second part, ‘The Andalusian Merchant’. But it was too difficult; we rehearsed another by Weelkes instead. I wondered why ‘Thule’ was so hard. I sang it with the piano. I bought a CD. Most of us have sung madrigals for years. What made these harmonies, words and interval leaps particularly difficult?