Ultrasone is proud to debut the only open-backed headphone in its legendary PRO Series, the PRO 2900. For the first time ever, Ultrasone is releasing both a standard, single cable version and a balanced, double cable version of a pair of headphones. With the PRO 2900, Ultrasone has struck a balance between powerful and accurate sound production, with the airy and natural sound characteristics of an open-backed headphone.