Subwoofer

FIG. 1 is a front perspective view of a subwoofer showing our new design; FIG. 2 is a rear perspective view thereof; FIG. 3 is a front view thereof; FIG. 4 is a rear view thereof; FIG. 5 is a bottom view thereof; FIG. 6 is a top view thereof; FIG. 7 is a side view thereof; and, FIG. 8 is an opposite side view thereof. The broken lines in the figures illustrate the portions of the subwoofer that form no part of the claimed design.