CLASS A ¡°PP¡± Voltage Tube: 2 x 12AU7 Voltage Tube: 1 x 12AX7 Electronic Electric Valve: 1 x 6Z4 Electronic Regulation: 1 x WY3, 1 x WY4 Input Sensitivity: 200mv SNR: less than 1mv (Hum) Channel Balance: less than 1dB Dimension: 430 x 380 x 140 mm Gross Weight: 8.00kgs