It is not marine blue, royal blue or ultramarine, but Yves Klein Blue, (International Klein Blue), and it differs because it has that special quality that creates a sense of falling into. Or being elevated by, the sound of music. The ‘pure idea,’ Klein called it. Perhaps as pure as the distillation of blue from lapis lazuli.
The work Heartbreaking by Angelo Badalamenti is very evocative of a deeper kind of blue, as is Beethoven’s Moonlight Sonata.
I’ve seen this blue once, in Amalfi after a late dinner, utterly immersive and non capturable. But I see it and feel it with certain piano compositions. The Greek word for senses evoking other senses is synaesthesia. Aisthesis is perception and , and Syn is union or together. I don’t taste the blue but I hear it.