... regulations.digital and watch hand display, different level measurementwith impulse, it can accurately test lower ... with external filterfrequency range : 10HZ-20KHZbasic configuration: main machine, microphone, fan cover, horologe screwdriver, briefcase, filter ... low level): 20dB-135dB(A),32dB-135dB(C),40dB-135dB(linearity)TL5660B(high level): 55dB-165dB(A),65dB-165dB(C),70dB-165dB(linearity)Frequency ...