The ornamental design for a speakerbox, as shown and described.
FIG. 1 is a perspective view of a speaker box showing my new design;
FIG. 2 is a front elevational view thereof;
FIG. 3 is a rear elevational view thereof;
FIG. 4 is a left side elevational view thereof;
FIG. 5 is a right side elevational view thereof;
FIG. 6 is a top plan view thereof; and,
FIG. 7 is a bottom plan view thereof.
The even broken line showings of a speaker box in FIGS. 1-7 are for illustrative purpose only and form no part of the claimed design. The dot-dash broken lines in FIGS. 1,3-5 and 7 define, but are not included in, the boundaries of the claimed design.