The Sony SRSD25 is a 2.1 channel computer speaker system outfitted with two 38mm speakers and a 67mm subwoofer that output a total of 25w of power through a built-in amplifier. … The Altec Lansing VS4121BLK multimedia system includes a pair of 3” mid-bass driver speakers and one 6.5” subwoofer. An upgrade from both the VS2421 and VS2521, the VS4121BLK offers an increased peak power output of 62w (versus 56w), an improved nominal power output of 31w (versus 28w), …