Bach put some of the notes in just for dogs and others for aliens, so when the Centauris show up with an old probe in tow and demand proof that it’s really human music, the rehearsals are a bit panicked. Lily’s orchestra has done command performances before, but not for enigmatic states of plasma with gravity rays in high orbit.
Some genius rigged them a “quantasonic resonance deviation heuristic” that will, purportedly, flash red if they go off-hyperkey. Lily’s going to ignore it. Human music. You want it, you got it, she thinks, and tunes up to tension of contact.