A trim panel (10) includes an integrally formed attachment member (14) for mounting an acoustic device (16), such as a loudspeaker, an exciter, a piezoelectric transducer, or the like, directly to the trim panel (10) without the need of a separate mounting member. The acoustic device (16) is attached to the trim panel (10) by use a twist and lock fastening feature (18) in the form of a ramp surface (24) that draws the acoustic device (16) toward the trim panel (10) as the acoustic device (16) is rotated about the attachment member (14). Once the acoustic device (16) is rotated into place, one or more detents (26) are provided on the trim panel (10) and one or more corresponding detent grooves or recesses (32) are provided on the acoustic device (16) to lock the acoustic device (16) securely in place. The integrally formed attachment member (14) enables the inner and outer surfaces (11, 12) of the trim panel (10) to be a generally continuous surface.