The ornamental design for a loudspeaker, as shown and described.
FIG. 1 is a front top perspective view of a loudspeaker showing our new design;
FIG. 2 is a rear top perspective view thereof;
FIG. 3 is a front elevational view thereof;
FIG. 4 is a right side elevational view thereof, the left side being a mirror image thereof;
FIG. 5 is a rear elevational view thereof; and,
FIG. 6 is a top plan view thereof, the bottom being a mirror image thereof.
The broken lines shown at the rear of the loudspeaker as seen in FIGS. 2 and 5, and the broken lines shown at the front of the loudspeaker as seen in FIGS. 1 and 3, represent the bounds of the claimed design; these broken lines and the area within these broken lines form no part of the claimed design. The broken lines seen in FIGS. 2 and 5 indicate an area for a rear connector panel; the broken lines seen in FIGS. 1 and 3 indicate an area for a front logo plate. The loudspeaker is shown broken away in FIGS. 1-5 to indicate indeterminate length.