From Digital Interface Handbook, Third Edition

4.10 AES42 Digital Microphone Interface

This digital microphone interface is based on the AES3 two-channel interface and includes options for powering and synchronization of microphones. Most digital microphones currently in existence employ conventional capsule technology with A/D conversion very close to the microphone capsule rather than direct digital transduction of the acoustic waveform. There are nonetheless some advantages to be had in using digital transmission of audio signals from microphones, principally the potential for higher quality and lower noise as a result of conversion close to the capsule and the avoidance of long cable runs in the analog domain at low signal level. A microphone that conforms to this standard is typically referred to as an AES3-MIC.

The AES42 standard33 notes that some patent rights may relate to the interface in question and that licensing of some elements may be required.

4.10.1 Principles

The AES42 (AES3-MIC) interface is a standard AES3 interface that also carries power for the microphone. There is also a proposal to adopt a slightly different XLR connector to the normal one, termed the XLD connector, intended to avoid the possibility of damaging equipment not designed for the power supplying capacity of this interface. The XLD connector is identified with a striped 'zebra' ring to distinguish it, but this is not mandatory and there is some disagreement about the need for it (some say that studio practice has managed adequately for years with some XLR connectors carrying phantom power and others not). A combination of coded grooves...


Products & Services
Audio Microphones
Audio microphones are designed for sound reception and recording applications (speech and music).
Microphone Chips
Microphone Chips are integrated circuits (IC) microphones.
Measurement Microphones
Measurement microphones are most commonly condenser microphones, which convert sound pressure to an output that is then converted into a reading such as sound pressure level (SPL).
Audio Cables
Audio cables transmit audible signals such as voice and music. They are designed to minimize noise and interference that can impair sound quality.  Audio cables connect an audio source such as a stereo or microphone to an audio receiver or output such as speakers. Most products are shielded to prevent electromagnetic interference (EMI), typically with a foil and/or braided shield.  
Audio Mixers and Consoles
Audio mixers and audio consoles are units that combine signals from microphones and/or line level sources to produce a combined signal or signals.

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