WD-222 is a passive two sub-frequency sound, using a 12-inch long-stroke woofer driver and a 1-inch tweeter drive.

WD-222是一款二分频无源音箱，采用了一只12英寸超长冲程低音单元驱动器和一只1英寸高音单元驱动器。

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The stereo unit is built around a two-way system featuring a soft dome tweeter and a powerful compact woofer loaded by a passive radiator, for each channel.

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Each speaker in this system has a tweeter, woofer and four-inch passive bass radiator on the back that moves a surprising amount of air.

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Philips SoundSphere speakers have a uniquely positioned tweeter and woofer with rigorous audio crossover engineering that minimizes interference and produces a more natural sound.

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