Astell&Kern AKR03 Special Edition JH Audio Roxanne Earphones with Gold Plated Smartphone Conversion Cable With careful consideration to the frequency response, output impedance and tonal characteristics of the AK240, Jerry Harvey has fine tuned the Roxanne-Astell&Kern edition to take maximum advantage and to squeeze every last bit of performance these tw The Astell&Kern logo embedded in the Carbon Fiber faceplates and engraved to the machined Billet Aluminum carrying case, both the Astell&Kern and Jerry Harvey Roxanne logos truly separate the AKR03 special edition from the original Roxannes. The JH Audio Roxanne are equipped with soundrIVe Technology, using Jerry Harvey Audio's newest proprietary mini quad drivers. Roxanne has a triple quad driver (12 drivers) configuration that offers the widest frequency range you'll ever hear. Variable bass output, adjustable from cable; user controlled low frequency drivers with the adjustable bass (0 to +15dB). Frequency ranges from flat bass response up to +15dB. (10Hz to 100 Hz) 4-pin cable connection with Machined Aluminum Collar mechanism provides a more secure and strong connection with earpiece and will also help to protect it from sweat and dust.