Nor1527 Impedance Tube

The Nor1527 acoustic impedance tube system is a comprehensive laboratory instrument for measuring the acoustic properties of materials including sound absorption coefficient, acoustic impedance, sound transmission loss, and related parameters. Operating in accordance with ASTM E-2611 (4-Pole Transfer Matrix Method), ASTM E-1050, and ISO 10534-2 (Transfer Function Method), the Nor1527 provides the standardized measurement data essential for acoustic material development, quality control, and simulation model validation. The system includes two tube assemblies with different diameters (100 mm and 30 mm) to cover the full measurement frequency range from 50 Hz to 6400 Hz. The large tube handles low-frequency measurements while the small tube extends coverage to higher frequencies. Four precision GRAS measurement microphones with a range of 10 Hz to 20 kHz provide the phase-matched acquisition required for accurate transfer function calculations. A built-in 20W power amplifier and 4-input/1-output analyser complete the self-contained measurement system, requiring only a PC running the supplied software for control and data analysis. Advanced analysis capabilities include Johnson-Champoux-Allard-Lafarge (JCAL) material model fitting, which determines the physical parameters of poro-elastic materials (porosity, flow resistivity, tortuosity, viscous and thermal characteristic lengths, and thermal permeability) from the measured acoustic data. These parameters can be exported directly to MSC Actran finite element software for acoustic simulation of complex structures incorporating the tested materials. For acoustic material manufacturers, automotive OEMs, aerospace companies, and research institutions across the GCC and internationally, the Nor1527 provides the laboratory measurement capability needed to develop, characterize, and quality-control acoustic materials and noise control solutions.