OPPO HA-1 (JP) [DAC built-in balance drive corresponding headphone amplifier] OPP-HA1JP-B Dimensions (W x H x D): 254 x 80 x 333 mm / mass: 5.9 kg power; AC100V (50 / 60Hz) / power consumption: 70 W (operation), 0.5 W (standby) Headphones recommended impedance: 32 - 600 Japanese manual URL (PDF):http://cdn2.oppodigital.jp/oppo/manual/HA-1-User-Manual-5-7-2014-JP.pdf