An apparatus for mounting an audio speaker within a wall such that the apparatus and speaker are attached to and supported by one or more wall studs and so that a face of the audio speaker is substantially flush with the wall. The apparatus broadly comprises a substantially rectangular box having a backwall and four upstanding sidewalls. One or more of the sidewalls is provided with an aperture, and inside the aperture is located a fixture assembly. The fixture assembly comprises a spacer mount through which is threaded a spacer having a bore. The spacer is threadably extendable and retractable, and can be extended to a length sufficient to contact the nearest wall stud. A fixture is then inserted into and through the bore in the spacer and is driven or screwed into the wall stud to as to secure the apparatus and speaker in position.