Panel absorber
Panel absorbers: Bass control through vibrating masses
Panel absorbers are specialized mass-spring systems . While porous absorbers often require enormous material thicknesses to be effective in the bass range, panel absorbers utilize the principle of resonance to efficiently convert low-frequency sound energy.
Structure and Function
A classic panel absorber consists of a vibrating panel (e.g., made of wood, metal, or plastic) mounted in front of a closed air volume. This air cushion acts like an elastic spring on which the mass of the panel vibrates.
Full-surface vibration
The entire panel vibrates on a soft foam layer. The heavier the panel and the softer the foam, the lower the absorption frequency.
Bending vibration
The plate is firmly clamped and vibrates on its own axis. The calculation is complex because material properties and the cavity filling interact.
Energy conversion and damping
When sound hits the panel, the energy is first converted into mechanical vibration energy . The actual absorption occurs through friction – either within the panel material or through additional filling of the air space with mineral wool, which dampens the vibration of the enclosed air.
Challenges of conventional systems
- Material fatigue: Mechanical stress and aging of foams can change the tuning over the years.
- Indoor air quality: For optimal effectiveness, mineral wool is often needed in the cavity, which poses risks due to fiber shedding.
The modern solution: HSA3 vs. panel absorber
The HSA3 also uses the resonance principle, but solves the energy conversion much more elegantly through micro-perforation:
- Maintenance-free & durable: Based on stable geometry instead of mechanical flexibility.
- Completely fiber-free: Achieves cushioning solely through viscous air friction in the pores – ideal for allergy sufferers.
- Lightweight construction: Controlled absorption with significantly lower weight and shallower construction depth than solid wood or metal structures.
The HSA3 is the perfect evolution for anyone who wants to solve low-frequency problems without bringing the disadvantages of classic heavy-wall systems into the room.