How thick do acoustic panels need to be?

TL;DR: It depends on the frequency you need to control. Mid and high frequencies (dialogue clarity, harshness) are absorbed well by panels around 25–50 mm deep. Low-frequency “boom” traditionally needs far more — often 100–300 mm of bass trapping. The exception is engineered, corner-loaded systems: C-ATS controls reflection, reverberation and resonance in a system just 50 mm deep, independently measured by BSRIA to BS EN ISO 354.

Thickness is really about frequency

A panel absorbs sound most effectively at wavelengths comparable to its depth. High frequencies have short wavelengths, so a thin panel handles them well. Low frequencies have long wavelengths, so porous absorbers must be deep — or moved into corners and tuned — to do anything useful down low.

Frequency band What it affects Typical depth (porous absorber)
High (2–4 kHz) Harshness, sibilance ~25 mm
Mid (500 Hz–2 kHz) Dialogue clarity, imaging ~50 mm
Low-mid (125–500 Hz) Muddiness, congestion 100 mm+
Bass (below 125 Hz) Boom, uneven seat-to-seat bass 200–300 mm (traps)

Why this usually costs you space

Because bass control traditionally means depth, conventional treatment ends up taking 100–200 mm off every wall once traps are added. Around a whole room that is a meaningful band of lost floor area — and in a high-value property that space is expensive. In tight retrofits, deep treatment often simply won't fit.

How C-ATS controls bass in 50 mm

C-ATS separates the three jobs and engineers each panel for its task rather than relying on raw depth:

  • Reverberation Control Panel — a broadband absorber whose measured absorption coefficient rises toward 1.0 across the mid and high frequencies (BSRIA, BS EN ISO 354).
  • Resonance Control Panelcorner-loaded for low frequencies. Placing low-frequency control where modal energy concentrates (the corners, including the ceiling corners) is far more space-efficient than lining walls with deep traps.
  • Reflection Control Panel — tuned as a clean reflector to protect imaging at the first reflection points.

The result is measured control of all three problems at just 50 mm — without surrendering the room. (More on the wider method: the complete home-cinema guide and The System.) To get a suggested 50 mm package for your room, try the free Room Selector.

FAQ

Are thicker acoustic panels always better?
No. Thicker porous panels absorb lower frequencies, but past the mid-range, more depth mostly costs you floor space. The smarter approach is to match each frequency problem with the right tool — corner-loading bass rather than over-deepening wall panels.

Can a 50 mm system really control bass?
Broadband porous panels can't do much at 50 mm in the deep bass — which is exactly why C-ATS uses a separate, corner-loaded Resonance panel measured for low-frequency performance, instead of relying on panel depth.

Is the performance independently tested?
Yes — C-ATS panels were tested by BSRIA to BS EN ISO 354 (Report 100241/1).

Where do the panels go?
Behind a finished, acoustically transparent surface, so they're invisible in the room.