Free-field microphone 4191

measurementexternally-polarizedfrequency

Free-field microphone for high-precision, free-field measurements with a wide frequency range/bandwidth of 3.15 Hz to 40 kHz. Type 4191 is designed for high-precision, free-field measurements where a wide bandwidth is required. Being externally polarized, Type 4191 must be used with a classical preamplifier. USE SCENARIOS • Precision measurements to 40 kHz • Premium class sound level meters • Equipment complying with IEC 61672 class 1 USE OF FREE-FIELD MICROPHONES At higher frequencies reflections and diffractions causes a pressure increase in front of the diaphragm of a microphone. If not corrected for, this would result in an increased output voltage. A free-field optimisation means that the frequency response of the microphone has been designed in such a way that the free-field response at 0 degrees incidence is flat. This microphone is optimised for use with the protection grid in place. Free-field microphones are commonly used for sound measurement in an anechoic chamber or far away from reflecting buildings, etc. Another area for free-field microphones is for general electroacoustic measurements like loudspeaker and microphone measurements. With an upper frequency of 40 kHz, Type 4191 is especially suited all high-precision electroacoustic measurements as well as general acoustic measurements where a robust and stable free-field microphone is required. Despite the 40 kHz upper frequency, this microphone is optimised to operate with the protection grid in place.