JBL4181是款高性能的次低音音箱,它采用了坚固的直接辐射式倒相箱体加上优良的460mm(18英寸)低频驱动单元,实现了平滑的低频响应,并能轻松的重放人耳可听的低频下限。4181能够很好的满足电影院和大部分扩音场合在播放模拟或数字信号时对提升低频效果的需求。w-frequency augmentation of either analog or digital soundtracks in motion picture theaters and for general sound reinforcement applications.