The genius of many of our greatest composers, German ones especially, is often seen in their writing for the female voice.

It has been my privilege over the past week or so to hear a truly wonderful series of performances from women singers that has underlined this point.

The first was nine days ago in the revival of the Royal Opera’s production of Richard Strauss’s Ariadne auf Naxos at Covent Garden, under the baton of Lothar Koenigs, the Music Director of Welsh National Opera.

This is an opera that presents not one but three superb roles for women: the passionate soprano of the title role, the flamboyant Zerbinetta with one of the hardest roles in the coloratura repertory (and a set piece aria to outshine even those of the Queen of the Night) and the intense young Composer.

The last role, created by the great German soprano Lotte Lehmann, is now usually entrusted to a high mezzo-soprano.

Practised exponents include Sarah Connolly, who was in superb voice at the Sheldonian Theatre on Friday night in the first concert of the Oxford Lieder Festival 2015, with accompanist Graham Johnson.

Her programme included songs by Schubert, Brahms and Hugo Wolf, a composer whose works seemed daunting, she said, when tackled in her student days but which were made to look a breeze as delivered here.

On Saturday, Opera on 3 gave us Wagner’s Tristan und Isolde, recorded at this summer’s Bayreuth Festival. Stephen Gould and Evelyn Herlitzius excelled in the title roles.

The beauty of radio, of course, is that one is able to do other things while listening.

My favoured activity this time was reading. My book was Thomas Hardy’s The Mayor of Casterbridge.

The tale was published in 1886, in which year, by coincidence, Tristan was first given at Bayreuth.