What's puzzling me is that what I hear doesn't match those FR charts. My Yamahas sound a bit weird but are still fun, they were my only pair for almost a decade and I didn't feel the need to upgrade until they developed a channel imbalance. But to me the Etymotics sound bad, almost phone-like, and I have a hard time understanding how what I hear could get any praise, much less the cult following they seem to have... It feels like a lot of $20 chifi IEMs could do better, and the 7Hz Zero actually do, hands down. Which is why I suspect some ear canal shape incompatibility (given their unusual insertion depth), a faulty unit, or something along those lines. I'm seeing an audio nerd friend soon, I'll ask her what she thinks about them, but at that point it would take some "Eureka moment" for me to keep them. Thank you for spending the time trying to help me though...