When and how did you first come across the Peterhouse Partbooks and how long has the ensemble been singing this music?

The summer before Blue Heron gave its first concert in the fall of 1999, I was over at the Von Huene Workshop in Brookline (in Greater Boston), browsing through music in a filing cabinet, when I came across a piece called Ave Maria Dive Matris Anne by someone I had perhaps never heard of before, one Hugh Aston. It was scored for five voice parts, exactly what we were planning for, and it looked quite wonderful. The edition was beautiful, too, with a complete scholarly apparatus and extensive notes, but easy to read from and obviously made by someone with a keen sense of visual aesthetics combined with practical understanding of what performers need. This editor, Nick Sandon, clearly knows what he’s doing, I thought, and oh look, he’s restored the tenor part, too! So I took the music home with me, read through it, and began to realise what a find I had made – or rather, what a treasure Nick Sandon and benevolent happenstance had delivered into my hands. Ave Maria Dive Matris Anne concluded our debut...