Kitt (from Knight Rider) LED Display - Driver Board
The Kitt display is basically a VU (Audio Power) meter reflected horizontally. To make things simple, Texas Instruments produce a chip called the LM3915 Dot/Bar Display Driver which does most of the hard work and is designed for exactly this application. The LM3915 senses analogue voltage levels and drives ten LEDs to produce a logarithmic 3 dB/step display.
You will also need the display board which is housed above this driver board and contains the six LED bar graph displays. Full details can be found at: http://reefwingrobotics.blogspot.com.au/