Yes, acoustic panels work, but only for the job they are built for. Acoustic slat panels absorb sound that is already inside a room, which shortens reverberation and makes speech clearer. They do not soundproof: they add little mass, so they barely change how much noise passes through a wall into the next room.
Key takeaways
- Acoustic panels control echo and reverberation (absorption); they are not soundproofing (insulation).
- Slat panels absorb mainly through the PET felt exposed in the gaps between timber slats, strongest at mid and high frequencies.
- The biggest gains come in hard rooms with glass, plaster, concrete and hard floors, such as offices, restaurants and open living spaces.
- Mounting on battens with an air gap and mineral wool extends absorption to lower frequencies.
- Compare products only on test reports that use the same standard and the same mounting.
Last reviewed: October 2026 by the Linegrain specification team.
Absorption or insulation: which problem do you have?
Most disappointment with acoustic panels comes from buying them for the wrong problem. Acousticians separate two quite different jobs.
Sound absorption deals with sound inside a room. When someone speaks in a meeting room with plastered walls and a hard floor, the sound reflects from every surface and keeps arriving at your ears for a fraction of a second after the words were spoken. That tail of reflections is reverberation. Absorbent materials turn part of the sound energy that strikes them into a tiny amount of heat, so each reflection comes back weaker. Absorption is measured in a reverberation room under ISO 354 (or ASTM C423 in North America) and condensed into a single-number rating and class under ISO 11654.
Sound insulation deals with sound travelling from one space to another: the neighbour’s television, the meeting next door, traffic outside. It depends on mass, airtightness and decoupling, and it is rated with single-number values such as Rw and DnT,w defined in ISO 717-1. In England, the sound insulation required between dwellings is set out in Approved Document E; adding decorative absorbers to a party wall is not a route to meeting it.
| Question | Sound absorption (acoustic panels) | Sound insulation (soundproofing) |
|---|---|---|
| What it changes | Echo, reverberation and noise build-up inside the room | How much sound passes through walls, floors and doors |
| Typical materials | Porous felt, mineral wool, wood wool, slat panels over felt | Dense boards, masonry, decoupled stud walls, acoustic sealant, heavy doors |
| Key ratings | αw and absorption class (ISO 11654), NRC/SAA (ASTM C423) | Rw, DnT,w (ISO 717-1), STC (ASTM) |
| Where it goes | Exposed surfaces inside the room | Within the separating construction itself |
| Will slat panels do it? | Yes | No, beyond a very small effect |
So if the complaint is “it is loud and echoey in here”, panels are the right tool. If the complaint is “I can hear next door”, the budget belongs in the wall.
How does an acoustic slat panel absorb sound?
A typical slat panel is a sandwich of two materials. Linegrain’s standard build is 2400 × 600 × about 21 mm: 12 mm MDF slats, each about 27 mm wide, bonded to a 9 mm PET felt backing with gaps of roughly 13 mm between slats. On a 40 mm repeat, that leaves about a third of the face (13 ÷ 40, or roughly 32%) as open felt.
The timber slats themselves are hard and reflective. Sound that hits the slat face partly reflects, and the rhythm of slats and gaps breaks up some high-frequency reflections. The absorption happens in the felt: sound waves enter the gaps, move air through the fibre mat, and lose energy to friction. Sound also travels sideways behind the slats where the felt is open to the gap.
Like any thin porous absorber, this construction works best at mid and high frequencies, which is where speech intelligibility and the “clatter” of a busy room sit. Low frequencies have long wavelengths and pass through a thin layer of felt with little loss unless there is depth behind it, which is why mounting matters (see below).
What can acoustic panels not do?
Being clear about the limits saves money and complaints later.
- They will not block noise between rooms. A 21 mm panel adds little mass to a wall, so airborne insulation barely changes.
- They will not stop impact noise. Footsteps from the flat above travel through the structure; that needs floor treatment.
- They will not cure bass boom on their own. Small rooms with strong low-frequency resonances need deeper absorbers or bass traps in addition.
- They will not quieten a noisy source. A loud extractor fan or a road outside is still loud; panels reduce the build-up of reflected sound, not the direct sound from the source.
- They are not a fire-stopping product. Any wall lining must meet the reaction-to-fire class required for its location; specify a fire-rated build where the project requires it.
When do acoustic panels make a noticeable difference?
Panels earn their place in rooms where most surfaces are hard and the main complaint is reverberation: meeting rooms, restaurants, hotel lobbies, classrooms, open-plan offices, podcast rooms, and living rooms with timber or tiled floors and large windows.
The standard way to estimate the effect is the Sabine equation. As set out in Montana State University’s acoustics course notes, reverberation time (the time for sound to fall by 60 dB) is approximately T60 = 0.161 × V ÷ A, where V is the room volume in cubic metres and A is the total absorption in square metres (each surface area multiplied by its absorption coefficient, then summed).
Worked example: one room, more panels
Take a hard meeting room of 6 × 5 × 2.7 m, so V = 81 m³. Assume the existing furniture, carpet tiles and surfaces add up to 12 m² of absorption. With nothing added, T60 = 0.161 × 81 ÷ 12 ≈ 1.09 seconds, which feels lively and tiring for meetings.
Each 2400 × 600 panel covers 1.44 m². For illustration only, we assume an effective absorption coefficient of 0.6 across the speech range, giving about 0.86 m² of absorption per panel. Replace that figure with the tested value for the build you actually buy.
Eight panels (11.5 m² of wall) bring the estimate down to about 0.69 s; sixteen panels to about 0.51 s. Two points stand out. First, the gains shrink as you add more panels, because each one adds to a growing total. Second, the starting condition matters: the harder and larger the room, the more panels it takes. The example simplifies reality: Sabine assumes sound is spread evenly through the room, coefficients vary by frequency, and the wall under a panel had a little absorption of its own. For a full method, see our guide on how many acoustic panels a room needs.
Where to put the panels
- Opposite parallel hard surfaces. Two bare facing walls cause flutter echo; treating one of them usually fixes it.
- At the height people talk. Panels from about seated head height upward intercept the strongest early reflections in meeting rooms and restaurants.
- On the ceiling when walls are glazed. In glass-walled rooms the ceiling is often the largest free surface; acoustic ceiling baffles, clouds and slat ceilings do the same job overhead.
- Spread rather than clumped. Several areas across different walls generally work better than one block in a corner.
How does mounting change performance?
The same panel can measure quite differently depending on what is behind it. Fixed directly to a solid wall, a slat panel absorbs mainly through its 9 mm of felt. Fixed on battens, it has an air cavity behind it, and the felt then sits further from the wall where air particle movement is greater for longer wavelengths.
Published research shows the effect clearly. In a study of a porous wall panel presented at the 23rd International Congress on Acoustics, Politecnico di Milano researchers measured absorption coefficients at 125 Hz rising from 0.04 with the panel flat on the floor of the test chamber to 0.13 with a 200 mm air gap and lining, and at 250 Hz from 0.36 to 0.67. The same paper notes that the air gap did not improve absorption in the central 400 to 1500 Hz range, and that single-number ratings are not appropriate below 250 Hz.
In practice this gives you three options:
- Direct fix to the wall: thinnest build-up, good for speech-range reverberation.
- Battens with an empty cavity: modest improvement at lower frequencies, plus a flat plane over uneven walls.
- Battens with mineral wool in the cavity: the strongest broadband result, useful in home cinemas, studios and restaurants with music.
Installation details for each are covered in how to fit acoustic wall panels.
How should you read an acoustic test report?
Absorption claims are only comparable when they come from the same test method and mounting. When a supplier sends a report, check:
- The standard: ISO 354 or ASTM C423 for the measurement; ISO 11654 for αw and class; ASTM C423 for NRC and SAA. Our guide to NRC ratings explains how those numbers relate.
- The mounting: a result measured with a deep air gap and mineral wool cannot be expected from the same panel screwed flat to plaster.
- The full frequency table: a single number hides where the absorption happens. For speech, look closely at 500 Hz to 2 kHz.
- The specimen: felt thickness, slat width, gap width and backing should match what you are ordering.
Linegrain shares fire and acoustic test reports for the specific build quoted rather than generic figures; see how we handle quality and testing. Browse the full range of acoustic slat panels to compare finishes.
FAQ
Will acoustic slat panels stop me hearing my neighbours?
No. Slat panels absorb sound inside the room they are fitted in; they add very little mass, so they do little to reduce noise passing through a party wall or floor. Blocking noise between rooms needs sound insulation: added mass, decoupled linings, sealed gaps and resilient layers.
How many acoustic panels does a room need to make a difference?
It depends on the room volume, how hard the existing surfaces are and how much reverberation you want to remove. In our worked example an 81 m³ room went from about 1.1 seconds to about 0.7 seconds with eight panels. Use measured absorption data for the actual build to plan a real project.
Do slat panels work better on battens than flat on the wall?
Usually at low frequencies, yes. An air gap behind a porous absorber, ideally partly filled with mineral wool, extends absorption to lower frequencies. Research on a porous panel found a 200 mm gap raised absorption at 250 Hz and below but did not improve the mid-frequency range.
Are acoustic slat panels good for a home cinema or podcast room?
They are a good start for controlling echo and early reflections, which makes dialogue and voice recordings clearer. Very small rooms with bass build-up also need deeper, low-frequency treatment in corners, and recording rooms that must be quiet need separate sound insulation work.
Specifying slat panels for a hard, echoey space? Send us the room sizes, finish and mounting you have in mind and we will quote the matching build with its test reports. Request a quote.