Abstract: A sound barrier panel comprising a substantially planer first wall, with a plurality of apertures defined in the first wall, a non-apertured second wall, a crown connecting the first wall to the second wall, a base connecting the first wall to the second wall, a panel interior defined by a spacing between the first wall, the second wall, the crown, and the base, a sound absorbing material disposed in the panel interior, and the second wall being contoured such that at least one continuous gap is formed between an inner surface of the second wall and the sound absorbing material, wherein the first wall, the second wall, the crown, and the base are formed of a pultruded material.