Free-Field Acoustic Environment
Fully Anechoic Chamber
Complete 6-wall wedge absorption system providing a true free-field acoustic environment above the design cut-off frequency. Engineered for transducer calibration, audio product certification, and precision NVH measurement.
Technical Specifications
Applications
- Loudspeaker & transducer measurement
- Microphone calibration (IEC 61094)
- Headphone & hearing aid testing
- Automotive NVH component testing
- Consumer electronics certification
- Acoustic research & development
Overview
A fully anechoic chamber eliminates all acoustic reflections through wedge-shaped absorbers installed on all six surfaces — walls, ceiling, and floor. The result is a free-field environment where sound propagates outward without boundaries, replicating an infinitely large outdoor space within a controlled laboratory setting.
HEMU Acoustics fully anechoic chambers are designed to achieve free-field conditions above the specified cut-off frequency (typically 80–100 Hz), with NRC values of 0.99 or higher. Our modular construction system enables chambers ranging from compact 5 m³ units for microphone calibration to large-scale 500+ m³ facilities for automotive component testing.
All chambers include an internal suspended wire floor grid for safe access, double-leaf wall construction for structural isolation, and an electromagnetic shielding option for EMC-sensitive applications.
Common applications include loudspeaker directivity measurements, headphone and microphone calibration, hearing aid testing, automotive component NVH characterization, and certification testing to IEC 60268-5, ISO 26101, and related standards.
Key Features
Superior Free-Field Accuracy
Designed to meet or exceed the free-field deviation criterion of ±1.5 dB across the working area, ensuring measurement repeatability.
Modular Construction
Factory-prefabricated panels for fast on-site assembly. Standard modular units ship in 6–8 weeks; custom projects in 12–16 weeks.
Structural Vibration Isolation
Inner shell isolated from outer shell via spring mounts, achieving >40 dB insertion loss against floor-borne vibration.
Access & Safety
Suspended wire mesh floor grid rated to 250 kg/m². Emergency lighting, ventilation, and intercom included as standard.
Custom Absorber Design
Wedge geometry optimized via FEM simulation for your target cut-off frequency. Fiberglass, melamine foam, or hybrid wedge options.
Compliance Documentation
Full acoustic acceptance test report provided. Data includes insertion loss, background noise level, and free-field qualification map.
Ready to discuss your requirements?
Our acoustic engineers respond within 24 hours.