Hert z Hcp4D D-Klass Stereo Amplifier Power Amplifier 4 X 145 Watt RMS output power: 85 watts x 4 at 4 ohms, 145 watts x 4 at 2 ohms, 290 watts x 2 at 4 ohms bridged Minimum bridged impedance: 4 ohms Channel modes: 4, 3, or 2 CEA-2006 compliant Bypass filter: Yes