Your tour includes your first concert at the Sydney Opera House in 25 years. How do you feel about performing in its renovated Concert Hall? 

The Sydney Opera House has always thrilled me. We even have a mosaic of the external view set into an alcove in our garden in London. We sang in the Concert Hall six times up to May 2000, which I remember as being unhelpfully dry acoustically. And I always got lost backstage. I’m hoping the renovations will have corrected these difficulties. But it was always special to be there.

The program is inspired by the beauty of Gregorian chant. Can you tell us about your choice of repertoire? 

Peter Phillips (centre) with The Tallis Scholars. Photo supplied

Gregorian chant underpinned everything that was good about polyphony in the 16th century and has continued to do this in the hands of some contemporary composers. The beauty of its melodies has been the inspiration for composers as wide-ranging as Jacob Obrecht (d. 1505) and Arvo Pärt (b. 1935), a journey which the 12th-century German abbess, Hildegard of Bingen, greatly helped on its way by adding to the traditional repertoire and...