Sony XM-ZR604. Total Harmonic Distortion (THD): 0.005 %, Signal-to-Noise Ratio (SNR): 97 dB, Impedance: 2 Ом. Depth: 265 mm, Height: 55 mm, Weight: 3100 g. Dimensions (WxDxH): 396 x 265 x 55 mm, Output power: 440 W