As the saying goes, the vacuum tube is to the audiophile what the crystal ball is to the fortune teller. It can see (or hear, in this case) all the hidden details, nuances, and secret whispers of a melody that the layman might miss. Enter the écoute headphones. These babies are like a master sculptor with an impossibly fine chisel, carving out every thumping bass note, every soaring soprano note, and every strum of a guitar string, with a precision that could make Da Vinci jealous. The vacuum tube in these headphones, dear friends, is like having Beethoven's ghost nestled on your head, personally conducting the 9th symphony into your ear canal. If Beethoven were a fan of Bluetooth 5.3, that is.