I'm sitting on a busy subway train in Manhattan, listening to some tunes. This is a normal situation, something I do a dozen times a week. What isn't normal is that I only hear my music, and I don't hear any of the train or crowd noise around me. Instead, my music is backed by white noise. No panhandlers or chatty kids or the screech of subway wheels on rails. Doppler Labs's Here One wireless earbuds are blocking out all that nonesense so I can focus on my tunes.