Rated conditions

When testing a microphone according to IEC standard, the microphone should be brought under rated conditions. This includes the microphone being connected to a specified load, supplied by rated power (if needed), placed in a sound field meeting free-field conditions (unless it is a close-talking microphone), and the microphone being placed at a distance from the source determined, whether the microphone is defined to be a far-field, near-field, or close-talking microphone. (Stated in IEC 60268-4, clause 4.2.2). (See “far-field microphone”, “near-field microphone” and “far-field microphone”).