Precise measuring microphone with linear frequency response. Electret measuring microphone for measuring systems and audio recordings. Ideal for measurements of PA systems, speakers and room acoustics. Suitable for combination with a spectrum analyser. Linear frequency for high precision weighted ball characteristics. Whole metal housing included in the box contents in practical storage box. Microphone clamp, thread adapter (9 mm/3/8 inch) and wind protection type: condenser (back electret)Operating principle: pressure receiver, FET preampPolar characteristics: ball range: 20 Hz – 20 kHzity: -37 dB (± 3 dB)Nominal impedance: 200 OhmNominal load pedance: 1000 Ohmax. Sound Pressure: 134dB (THD)