Text: Phase, as the term is used in audio, usually refers to loudspeaker hookup. In a stereo system, the two loudspeakers should be working in tandem, their cones pushing and pulling at the same time, rather than working against each other. When this condition holds true, the two speakers are said to be acoustically in phase. Conversely, when one speaker pushes forward while the other pulls back, the speakers are out of phase, which usually causes loss of bass and uneven sound. When speakers are out of phase, the situation can easily be corrected by reversing the connections to one of the speakers.

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