KEF Q500 Floorstanding Loudspeaker - American Walnut (Single) The Q500 features a specially-voiced 5.25 inch aluminum Uni-Q driver and 1 inch vented aluminium dome tweeter. Based on our state-of-the-art HF driver, the Q500 boasts a much larger dome tweeter for increased sensitivity and distortion-free power handling. Below the Uni-Q driver array are three stacked 5.25 inch bass drivers working in tandem to quickly and efficiently produce a range of low frequencies. The Q500 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 Q500, resulting in a rigid connection that eliminates any rocking resonances.