The Larson Davis 426A12 Outdoor Microphone has been designed for permanent outdoor use in any weather condition. It is constructed of stainless steel to resist corrosion, and its profile minimizes both wind resistance and acoustic reflections. It includes a rain hat, wind screen and bird spikes and an electrostatic actuator which can be controlled remotely for on-site calibration checks. With the proper choice of microphone, it can provide frequency response characteristics consistent with precision sound level meter requirements for free-field or random incidence measurements. Equipped with A, C and Z-weighting filters and a 20 dB gain, the 426A12 is ideal for use with any electronic sound measurement system.

A hydrophobic membrane vent and replaceable desiccant cartridges prevent moisture from reaching the microphone through the vent. The saturation status of the desiccant cartridges can be determined remotely using signals from internal temperature and humidity sensors, as well as visually through an observation window.

The Larson Davis Model 831 sound level meter is the ideal complement to the Model 426A12 Permanent Outdoor Microphone for Noise Monitoring Systems.