Subwoofer

FIG. 1 is a front view of the ornamental design of a subwoofer.

FIG. 2 is a rear view of the design of the subwoofer of FIG. 1 .

FIG. 3 is a left view of the design of the subwoofer of FIG. 1 .

FIG. 4 is a right view of the design of the subwoofer of FIG. 1 .

FIG. 5 is a top view of the design of the subwoofer of FIG. 1 .

FIG. 6 is a bottom view of the design of the subwoofer of FIG. 1 ; and,

FIG. 7 is a perspective view of the design of the subwoofer of FIG. 1 .

The broken lines in the figures depict portions of the subwoofer that form no part of the claimed design.

The shade lines in the Figures show contour and not surface ornamentation.