effects speaker: Loudspeakers in a multi-channel system that reproduce the ambient effects, the off-screen effects and thus the spatial effect of certain scenes. In the home cinema, they are placed about 10 degrees to the side behind the audience seats and slightly above head height. At Dolby Digital (see Dolby Digital) there are discrete left and right channels. With Dolby ProLogic (see Dolby Digital ProLogic), a mono signal is reproduced in the effect speakers. Effect speakers should not be consciously noticed, as they distract from what is happening in the film on the screen. In good films, effects are therefore usually used very sparingly.
