The 81ST4 is the second in our line of mini landscape subwoofers designed for local zone bass performance. It can be configured with 1 satellite speaker as a mono channel, 2 satellite speakers as a 2.1 stereo or with multiple satellite speakers in small patio areas. James’ subterranean subwoofer’s direct burial, 8” compression band pass design creates unrivaled low end frequency response. External hooded port, aircraft/marine grade aluminum enclosure and stainless steel hardware provide for increased protection in extreme weather.