... .4 Ambient temperature,-30 ~ +501.5 degreeRelative humidity, ≤95%1.6 Atmospheric pressure, 80~110Kpa 1.7 Defend grade, IP 672 ... , 50mA,≤0.2A. 2.5 frequency response , 300~3400 Hz2.6 output sound signal ,1.5V / 300Ω2.7 loop circuit impedance ... ,1KΩ2.8 distortion factor ,≤2%2.9 Output power amplification ,0~35W (load impedance 16Ω)3.0 Installed ...