"The mid-frequency portion is reproduced both by the midrange and side woofers, but with a precise phase-amplitude relationship that causes output behind the speaker to be minimized. The low- and high-frequency bands are reproduced normally, by the side woofers and tweeter, respectively.
"This is a polar plot of the mid and low bands combined. Note that these plots are made with the center of rotation directly in front of the midrange driver, hence the apparent rearward shift in the bass.
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