Subwoofer Operation T18B - V2 2 x 18" for Arenas - Big Venues AT218B2 x 18" for midsized Venues ATL18B 1 x 18" flybass for AT110 S118B1 x 18" for midsized Venues WS118B1 x 18" for midsized venues TR18BA 1 x 18" bass for TR Active U15B 1 x 15" for U6 & U8 U10B 1 x 10" for U4
