People call audio mysticism “mysticism” because there’s so much about it that’s uncertain and unprovable. Headphone forums love using precise instruments to stay objective, to determine whether a pair of headphones is truly Hi-Fi — after all, Hi-Fi originally meant high fidelity. High fidelity means reproducing a song exactly as it was originally recorded… So an audio device that boosts the bass, boosts the treble, boosts this and that is, in theory, violating the original vision of Hi-Fi. On this point, the various instrument tests on headphone forums really aren’t wrong in their direction. But there’s this concept called “listening impression.” That’s where the mysticism begins. An earbud might have tremendous playback capability on an audio oscilloscope, but that doesn’t beat a bunch of people listening and saying it “sounds bad.” One sentence — “sounds bad” — can drag a high-end earbud through the mud.