Recording and Voice Processing, Volume 2

Appendix 4Microphone Pairs

A4.1. Introduction

The use of a pair of microphones makes it possible to record stereophonic sound. There are several techniques, and it is important to know whether the recording you are about to make will be compatible with monophony or not.

The directionality of the microphones used can be omnidirectional, cardioid or hypercardioid, making sure that their directional lobes are homogeneous (no or little alteration due to an obstacle, the microphone itself can be one) and matched.

A4.2. The AB pair

For this pair, the microphones are separated by 40 cm up to several meters. This is the pair generally used to capture large vocal or orchestral ensembles.

The microphones to be used should be omnidirectional for their excellent bass response and for their directionality, which will highlight the acoustics of the recording location.

If the space is very reverberant or if the distance is very great, cardioid or hypercardioid microphones are preferred.

In an AB pair, the phase of the audio signals is followed and there is no prioritization phenomenon; therefore, the signal is compatible with monophony.

Figure A4.1. Principle of the AB pair

Figure A4.2. An AB pair

A4.3. The XY pair

This so-called phase coincidence pairing uses two cardioid microphones ...