If you’ve ever wondered what a castrato sounds like, there are recordings (from 1902 and ’04) of Alessandro Moreschi, a member of the Sistine Chapel Choir. It’s a strange sound, even allowing for his dodgy tuning, but the top of the voice has extraordinary freedom. The heyday of the castrato – when they were the superstars of the operatic world with fees to match – coincided with one of the most fruitful periods of Handel’s life. Many of the star countertenors had nicknames and drew from Handel and his contemporaries some now classic roles. Senesino (Francesco Bernardi) inspired, among other parts, the title-role of Giulio Cesare (try Jennifer Larmore in ‘Va tacito’). Caffarelli (Gaetano Majorano) coaxed from Handel one of his most heart-melting arias ‘Ombra mai fù’ in Serse (let Andreas Scholl stand in here). Giovanni Carestini (celebrated stylishly by Philippe Jaroussky) famously crossed swords with Handel but, according to Charles Burney, sang like an angel even as his voice darkened and deepened. Farinelli (Carlo Maria Michelangelo Nicola Broschi) made a huge impact in London in Hasse’s Artaserse (Franco Fagioli, caught live, does ‘Per questo dolce amplesso’ with style). Nicola Grimaldi (also known as Nicolini) created the role of Rinaldo for Handel and in so doing helped establish the composer in London. The Gramophone Award-winning set under Hogwood finds David Daniels on thrilling form. Gaetano Guadagni, a very serious artist by all accounts and the beneficiary of three new arias in Handel’s Messiah, created the role of Orfeo in Gluck’s opera; his simple, mellifluous approach found favour with contemporary audiences. Perhaps the restrained, gently ornamented approach of Bernarda Fink comes close to Guadagni’s style? An 11-year-old Mozart encountered Venanzio Rauzzini in Vienna and wrote the title-role of Lucio Silla as well as Exsultate jubilate for him – Carolyn Sampson is well-nigh faultless here). Two modern muses? James Bowman for Britten, in Death in Venice,and Bejun Mehta for George Benjamin and his Written on Skin.