The most simple is the most impressive: Listen to the music at 1'21''. Ta-ta! Ta-ta! The harpsichord is not penetrating the orchestral sound. It's totally different, not from this world.
The orchestra is sloping, attacking, slowing down, and the harpsichord just does not get it. The solo in the fifth minute is so painfully lonely.
Composer: Francis Poulenc
Work: Concert Champêtre, II. Andante
Recording: Mahan Esfahani, BBC National Orchestra of Wales, Martyn Brabbins