A speaker assembly includes a speaker mounted within a housing having a front plate and a base plate. The speaker is inclined with respect to the front plate. The base plate includes one of an inclined type structure, a convex type structure, a radial rib type structure having radial ribs, and an uneven structure having projections. The front plate includes holes of certain shapes such as having two half holes formed on opposite sides of front plate and communicating with each other through a common opening formed between the two half holes.