Acoustic Treatment Calculator — Room Treatment Coverage

Start with bass traps in all corners (they have the biggest impact). Next, treat first reflection points on side walls and ceiling. Then add absorption panels to remaining wall areas. Finally, add diffusion to the rear wall.

Mixing rooms: 0.25-0.35s. Recording rooms: 0.3-0.5s. Podcast booths: 0.2-0.3s. Practice rooms: 0.4-0.6s. Lower RT60 means a drier, more controlled sound. Very low values (<0.2s) can sound unnaturally dead.

Thicker panels absorb lower frequencies. On ISO 354 random-incidence data (e.g. Owens Corning 703 / Roxul mineral wool), 50 mm panels are effective down to roughly 250-300 Hz and 100 mm panels reach down to about 125 Hz. For genuine bass control below ~100 Hz use thicker panels, a deep corner bass trap, or mount 50 mm panels on a large air gap (the quarter-wavelength rule pushes absorption lower).

Diffusers scatter sound energy rather than absorbing it, maintaining a sense of space while controlling reflections. They are most useful on the rear wall of mixing rooms. For small rooms (<15 m²), focus on absorption first — diffusion needs distance to work effectively.