Nixon’s The Wire iPhone ($90) is an example of the older approach at play, in essence, a fashion company doing its best to make a big pair of earphones more visually appealing, here, with metallic logo-branded discs as the theme. Actually, Nixon has taken its $40 Wire 8mm earphones—normally offered in six colors—and added a combination microphone and single-button remote control to the cord for a somewhat staggering $50 premium.…