A DealNews exclusive! Electronics Expo offers dealnews readers the Polk Audio DSW PRO 300-watt 8" Powered Subwoofer, model no. DSWPRO440WI, for $499. Coupon code "DEALNEWSAVE" drops it to $257.81. With free shipping, that's the lowest total price we could find by $142. It features a 25Hz to 160Hz frequency response, 300 watts of peak power, downward firing slot port, and more.