Pressure Field Microphones 
 

A pressure-field is characterized by sound pressure that maintains uniform magnitude and phase throughout the field. This type of sound field can be closely approximated in confined spaces that are small relative to the wavelength of sound, like in couplers, cavities, and artificial ears. Pressure-field microphones are specifically designed for accurate measurements in these controlled environments, ideal for calibration setups, audiometric devices, and other applications involving enclosed or highly reflective spaces.