½-inch Diffuse-field Microphone, Prepolarized

Prepolarized diffuse-field ½-inch microphone Type 4942 is optimised for general random-incidence measurements and for standardised noise measurements in accordance with ANSI standards. And being prepolarized it can connect to CCLD input conditioning.

USE SCENARIOS

• Diffuse-field measurements
• In-car measurements
• High humidity conditions

USE OF DIFFUSE-FIELD MICROPHONES

A diffuse-field microphone, also called a random-incidence microphone, is designed to have a flat response when signals arrive simultaneously from all directions. They should therefore not only be used for measurement in reverberation chambers, but in all situations where the sound field is diffuse, or where several sources contribute to the sound pressure at the measurement position. Practical examples are indoor situations, where the sound is reflected by walls, ceilings, and objects in the room, or measurements inside a car.

ROBUSTNESS

The microphone is capable of withstanding the IEC 68-2-32 1 metre drop test. 

CALIBRATION

The sensitivity can be calibrated at 250 Hz by using Pistonphone Type 4228 with ½-inch Adaptor DP 0776. The actuator response can be measured using Actuator UA 0033. The random-incidence response can be obtained by adding the type-specific, random-incidence correction to the actuator response. Please note that this microphone is not suitable for pressure-field measurements.