The acoustic material market is dominated by three families: PET acoustic panels, wood wool boards, and melamine foam. Each has distinct strengths — and the right choice depends entirely on your space type and acoustic goals. This guide compares all three using DIN 18041 criteria and real frequency-specific data.
The 3 Major Acoustic Materials
PET Acoustic Panel
Polyester fiber · Lightweight · 107 colors
Wood Wool Board
Wood fiber + cement · Natural texture
Melamine Foam
Ultra-light · Broadband absorption · Economic
NRC Absorption Performance Comparison
| Material | NRC |
|---|---|
| Melamine 50T | 0.95 |
| PET 24T | 0.90 |
| PET 12T | 0.84 |
| PET 9T | 0.79 |
| Wood Wool 35T | 0.75 |
Frequency-Specific Characteristics — The DIN 18041 Perspective
NRC is just an average. What matters for DIN 18041 compliance is frequency-specific performance across 250–2,000 Hz. Each material has a distinct absorption profile:
차음(Sound Insulation)과 흡음(Sound Absorption)의 차이를 먼저 이해하고 싶다면? 차음 vs 흡음 기초 개념 가이드를 먼저 확인하세요.
PET Panels — Mid-to-High Frequency Specialist
PET panels excel from 500 Hz upward, with absorption coefficients exceeding 1.0 at 1,000 Hz+. At 12T, 250 Hz absorption reaches 0.62 — sufficient for DIN 18041 Group B4 office requirements. At 24T, the profile extends down to 400 Hz (α ≥ 0.85), suitable for Group A3–A4 meeting rooms. The key advantage: 107 customizable colors make PET the only material that combines performance with design flexibility.
두께별 흡음계수 차이가 궁금하다면? PET 흡음재 두께별 비교(9T·12T·24T)를 자세히 알아보세요.
Wood Wool Boards — Mid-Frequency Anchor
Wood wool boards provide steady, broad absorption centered on mid-frequencies (500–1,000 Hz). Their cement base makes them semi-noncombustible (준불연, Korean standard) and extremely durable. NRC 0.75 at 35T is lower than PET, but the natural texture and visual warmth make them the preferred choice for exposed-ceiling designs in lobbies, restaurants, and auditoriums.
Melamine Foam — Lightweight Broadband Absorber
At 50T, melamine foam delivers NRC 0.95 with excellent absorption from 500 Hz upward (α ≥ 0.90 at 1,000–4,000 Hz). Direct-mounted, 250 Hz absorption is moderate (0.20–0.50 depending on formulation). However, adding a 75 mm air gap behind the foam dramatically improves mid-to-low frequency performance — 250 Hz absorption jumps to approximately 0.65–0.75, making it competitive with thicker panel systems.
Weighing only ~1.6 kg/m² at 50T, melamine foam remains the lightest option by far. When installed with an air gap (the standard practice in ceiling applications), it provides broadband absorption suitable for offices and studios alike.
Why Air Gaps Matter — The Hidden Performance Booster
An air gap is the empty space between the acoustic material and the wall or ceiling behind it. When you mount a 50 mm melamine foam panel with a 75 mm gap behind it, the total acoustic depth becomes 125 mm — and the foam’s absorption at low-to-mid frequencies improves dramatically.
| Frequency | 50T Direct Mount | 50T + 75 mm Air Gap (est.) | Improvement |
|---|---|---|---|
| 250 Hz | 0.20 | 0.65–0.75 | ▲ +225% |
| 500 Hz | 0.55 | 0.90–0.95 | ▲ +70% |
| 1,000 Hz | 0.90 | 0.95–1.00 | ▲ +8% |
| 2,000 Hz | 1.00 | 1.00 | — |
| 4,000 Hz | 0.92 | 0.95 | ▲ +3% |
* Direct mount data: Sound Service UK / SINOYQX published specifications. Air gap estimates based on acoustic engineering principles — air gaps shift the effective absorption curve toward lower frequencies by increasing the acoustic depth.
In real-world installations, ceiling-mounted melamine foam almost always includes an air gap (the plenum space above the ceiling grid). This means the “with air gap” data better represents actual installed performance.
"PET wins on color and customization, wood wool on natural aesthetics, melamine on weight-to-absorption ratio — and with an air gap, melamine covers the full spectrum. There is no single best material — your space's purpose determines the answer."
Detailed Comparison Table
| Specification | PET Acoustic Panel | Wood Wool Board | Melamine Foam |
|---|---|---|---|
| NRC (typical) | 0.84 (12T) | 0.75 (35T) | 0.95 (50T) |
| Frequency Strength | Mid-to-high (500 Hz+) | Mid (500–1,000 Hz) | Broadband (500 Hz+; with air gap 250 Hz+) |
| Fire Rating | Fire Retardant (방염) | Semi-Noncombustible (준불연) | Fire Retardant (KR) / Semi-NC (intl) |
| Weight (per m²) | 2.4 kg | 12 kg | ~1.6 kg |
| Colors | 107 custom | Natural (5 types) | White/Grey |
| Texture | Felt/Fabric | Natural wood | Sponge |
| Durability | High | Very high | Moderate |
| Installation | Easy (adhesive/clip) | Professional needed | Very easy |
| DIN 18041 Match | Group B4 (offices) / A3-A4 (24T) | Group A (auditoriums, lobbies) | Group B4 (offices, with air gap) / B3 |
DIN 18041 A/V Ratio — How Much Do You Need?
DIN 18041 Group B spaces use the A/V ratio (equivalent absorption area / room volume) to determine the required amount of acoustic treatment. Here is what each space type demands:
B3 — Cafeterias & Labs (A/V ≥ 0.20)
Mid-duration stay spaces. A 100 m³ room needs at least 20 m² of equivalent absorption. Melamine foam 50T ceilings (with air gap) or PET 9T partitions are effective solutions.
PET 9T / MelamineB4 — Offices (A/V ≥ 0.25)
Noise reduction and comfort for all-day work. A 150 m³ office needs at least 37.5 m² equivalent absorption. PET 12T wall panels covering 40% of walls is the standard solution.
PET 12T recommendedB5 — Call Centers (A/V ≥ 0.30)
Spaces needing maximum noise reduction. Both walls and ceilings require treatment. PET 12T walls + melamine ceiling is a proven combination.
PET 12T + Melamine comboGroup A3/A4 — Meeting Rooms
Controlled reverberation time for speech intelligibility. PET 24T or wood wool boards provide the mid-frequency absorption needed to hit T target values.
PET 24T / Wood WoolSpace-Specific Combination Recommendations
Office
PET 12T walls + carpet tile floors is the most common combination. Choose from 107 colors to match your brand CI for spatial identity.
PET 12T recommendedEducational Facility
PET 24T or wood wool for large-area reverberation control. Fire-retardant certification is mandatory for these facilities — verify documentation.
PET 24T / Wood WoolStudio
Melamine foam 50T with air gap (broadband) + PET 24T (mid-to-low frequency) covers the full spectrum. Strategic reflective surface placement is critical for proper acoustic design.
Melamine + PET 24TRestaurant / Cafe
Aesthetics and acoustics both matter in dining spaces. All three materials offer distinct advantages — choose based on ceiling structure and design intent.
Aesthetic appeal matters in dining — PET is widely used for its design flexibility. Available in 107 colors with diverse pattern options.
Design-forward choicePreferred for its unique natural texture. Full Pantone color range available for custom finishes that harmonize with interior design.
Natural texture choiceNo ceiling thickness limit — 100T+ possible. Top choice for open-ceiling layouts requiring strong mid-to-low frequency absorption. Lightweight (safe if detached), and internationally rated semi-noncombustible for multi-use occupancy.
Primary pick for open ceilingsFrequently Asked Questions
Q. Can I mix different acoustic materials in one space?
Yes, and it is actually recommended. For example, PET panels on walls (mid-to-high frequency) combined with melamine foam 50T on ceilings (broadband with air gap) covers a wider frequency range. DIN 18041 calculates the total equivalent absorption area across all surfaces, so mixing materials helps meet the target across the full 250–2,000 Hz band.
Q. Do all three materials have fire-retardant certification?
Yes. PET panels carry fire-retardant (방염) certification under Korean fire safety standards. Melamine foam is fire-retardant (방염) in Korea and semi-noncombustible (준불연) internationally. Wood wool boards achieve semi-noncombustible (준불연) rating. All three are approved for multi-use facilities per Korean fire code.
Q. How do I calculate the required amount of acoustic material?
For DIN 18041 Group B4 (offices): Room volume (m³) × 0.25 = required equivalent absorption area (m²). Then divide by the material’s NRC to estimate physical coverage. Example: a 150 m³ room needs 37.5 m² absorption. With PET 12T (NRC 0.84), that means approximately 45 m² of panel coverage.
The Formula Is a Starting Point — Not the Finish Line
The A/V ratio calculation above gives you a reliable baseline, but real-world acoustic requirements vary significantly depending on the space type, occupancy patterns, ceiling height, furniture density, and how the room is actually used. Two rooms with identical floor areas can behave very differently acoustically.
That’s why Tornex conducts 3D acoustic simulation prior to installation, including auralization — letting you hear how the treated space will sound before a single panel goes up. After installation, on-site RT60 measurement confirms the result. This before-and-after verification is what separates a professional acoustic solution from a best guess.
When selecting an acoustic specialist, look for firms that offer pre-installation simulation and post-installation measurement — not just product supply.
The Optimal Acoustic Solution for Your Space
Tornex is your total acoustic solution partner — PET, wood wool, and melamine all under one roof.
PET Acoustic Panels → Wood Wool Boards → Melamine Foam →