Wagner’s opera Lohengrin premiered in 1850, conducted by Liszt. Its prelude is a ravishing depiction of the Holy Grail descending from heaven to earth, then reascending, structured as one long orchestral crescendo and decrescendo built on a single theme. It opens with divided high-register violins, plus an ethereal solo violin quartet in harmonics, and flute. The rest of the orchestra enters gradually, and it’s only for a brief period at the very centre, marked by two cymbal clashes, that everyone plays. The final chord is from the violin quartet alone. Brahms’s Double Concerto of 1887 was a gesture of reconciliation to Joseph Joachim, dedicatee of his Violin Concerto, following a rift in their friendship. Consisting of a passionate Allegro, a dignified and touching Andante, and a folky Rondo finale, it’s a beautiful fusion of dark colourings and delicate textures, with its parts lovingly, equally balanced.