KEF R900 Floorstanding Loudspeaker - Gloss White (Pair) The R900 features a 5.25 inch Uni-Q driver array, which consists of both mid-and-high-frequency drivers. The purpose of the array is to have both frequencies coming from the same place, allowing them to integrate perfectly and create a convincingly natural sound. The R900 floorstanding speaker also features two 8 inch low-frequency drivers above and below the Uni-Q array, which ensures a clean, deep and uncompressed bass output with superb dynamics. The R900 sits on an aluminum plate supported by four steel "plinth" spikes with locking knobs for easy height adjustment. The plinths also serve to ground the R900, resulting in a rigid connection that eliminates any rocking resonances. Our 'tangerine' waveguide technology helps to disperse the higher frequencies produced by the R900 evenly across a wider angle to flood your listening room with an intricate and refreshingly natural soundfield. The R900 pairs perfectly with the rest of our R Series home theater speakers, from center channels to subwoofers, to create a three-dimensional soundstage that makes movies and television sound that much more believable.