SoundTube LA808I-II-WH 3 Way Line Array Speaker (White) - 4.5"NOT a subwoofer, the SoundTube LA808i II is designed to increase the directivity of low frequencies in SoundTubes Line Array system. It can be used only in conjunction with the LA880i II 3 way line array. The use of the LA808i II is recommended in spaces that have a large reverberation time. When a single unit is added to the LA880i II, directivity of low frequencies is increased by up to an octave lower than with the LA880i II alone. The products