What Does A 3” Acoustic Panel Actually Absorb? 3” Acoustic Panels absorb deeper into the lower mid frequency range while also controlling higher frequency reflections and general echo. This is also where our Ultacoustic open frame design becomes increasingly important by allowing sound to absorb through the front, sides, and rear of the panel instead of only the face surface. Compared to thinner panels, 3” panels provide increased absorption for: • Lower mid frequencies • Vocal range • Room refl