He leído por ahi que lleva un ampli independiente para el subwoofer, podría ser el potenciómetro para éste.
http://proformind.bl...onda-s2000.html
"Inside, Scott invested the same amount of meticulous detail spent on the exterior by swapping the seats, door panels, steering wheel, center console, shift boot, shift knob, radio door, and floor mats with those found in the S2000 CR. A ZOOM Engineering rear view mirror was added for some additional flare, along with a plethora of ice: Beats are dropped vía a Pioneer Bluetooth head unit, Focal K2P components, a JL Audio 450/4 amp for highs/mids, a JL Audio 500/1 amp for his subwoofer, a JL Audio 10w6 driver, a JL Audio S2000 stealthbox, and a relocated Odyssey 925 battery in the trunk."