PLACID Instruments Impedance Tube for material sound absorption and transmission loss testing. The PLACID Instruments Impedance Tube measures normal-incidence sound absorption and transmission loss of acoustic materials using the transfer-function method. It enables quick, repeatable material screening with small samples, making it ideal for R&D and quality control. Key Features Normal-incidence absorption coefficient and transmission loss via transfer-function method. Small sample sizes; rapid set-up and repeatable measurements. Exchangeable tube sections to target different frequency bands (low to high). Multi-microphone positions for accurate standing-wave decomposition. Software workflow for calibration, measurement, and reporting. Applications Material acoustics characterization for product design, benchmarking, and process control. The impedance tube helps engineers predict in-product performance by quantifying how materials absorb and block sound at normal incidence. Automotive NVH & Transportation Screen foams, felts, fiber mats, barrier layers, and composites used in headliners, carpets, door panels, dash insulators, trunk liners, and electric-vehicle (EV) enclosure treatments. Optimize absorption peaks and broadband performance to reduce cabin noise, motor whine, and road/tires contributions. Use cases: supplier material approval, PPAP/QA checks, resin/process drift detection. Targets: absorption coefficient vs frequency, normal-incidence TL for multilayer stacks. Building & Architectural Acoustics Evaluate ceiling tiles, wall liners, porous absorbers, membrane barriers, and composite panels. Use normal-incidence absorption data to guide room acoustics design and product selection prior to full-scale reverberation chamber tests. Use cases: product development, supplier comparisons, incoming inspection. Targets: tuned mid/high-frequency absorption, multilayer barrier-absorber stacks. HVAC, Duct Liners & Appliances Characterize duct liners, acoustic foams, and insulation wraps for air handlers, compressors, and white goods. Improve tonal-noise damping and broadband attenuation while balancing thickness/weight. Use cases: intake/exhaust noise mitigation, fan-whine reduction, panel buzz control. Targets: absorption at blade-pass frequencies, leakage-related tonal suppression. Electronics, Audio & Consumer Products Screen speaker grille fabrics, mesh/vent foams, microphone windshields, and device liners. Optimize acoustic transparency vs attenuation trade-offs for audio quality and perceived product sound. Use cases: rub & buzz risk reduction, vent tuning, accessory material selection. Targets: frequency-selective absorption, TL of thin films and laminated stacks. Why an impedance tube? Compared to full-scale reverberation testing, an impedance tube offers fast iteration with small samples, controlled boundary conditions, and repeatable metrics that correlate with material performance in real products. Included / Typical System Modular tube sections, microphones with spacers, calibration accessories, data-acquisition interface, and measurement software (actual contents may vary by region/configuration). Standards & Methods ISO 10534-2 / ASTM E1050 (normal-incidence absorption using transfer-function method) ASTM E2611 (normal-incidence transmission loss) Downloads Download Brochure (PDF) Product Page (PLACID Instrents) Ordering & Support Brand: PLACID Instruments Distributor: Placid Asia Request a Demo Get a Quote Contact Placid Asia Notes Use the brochure for detailed specs, frequency ranges, and microphone configurations. Custom tube diameters and fixtures available on request. Demo Video impedance tube, normal incidence absorption, transmission loss, transfer function method, ISO 10534-2, ASTM E1050, ASTM E2611, acoustic materials testing, NVH materials, duct liner acoustics, architectural absorbers, audio vents