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ZX8903-8904
Sound Absorption Impedance Tube - Normal-Incidence Sound Absorption Coefficient and Specific Acoustic Impedance Measurement
The ZX8903 Sound Absorption Impedance Tube measures the acoustic properties of small material specimens using the two-microphone transfer-function method. Used with ZXONIC microphones, ZX6500 Dynamic Signal Analyzers, source drive and ZDS Software, it determines normal-incidence sound absorption coefficient, reflection coefficient, specific acoustic impedance and admittance. Available with 100 mm and 29 mm tube sections, the ZX8903 supports material research, product development, quality comparison and laboratory teaching. Looking for a complete measurement system? Explore the ZX9932 Impedance Tube System for Sound Absorption.
The system is designed for fast, repeatable testing of small specimens, with clear software-guided operation, automated plotting, and report-ready results in accordance with ISO 10534-2 (and related references).
OverView
The ZX8903 / ZX8904 is the sound absorption tube component of the ZX9932 measurement system. A material specimen is mounted at the end of a rigid, airtight tube, and a loudspeaker excites the air inside. Two microphones measure sound pressure at defined positions. The transfer function between these positions is used to separate incident and reflected waves and calculate the specimen’s acoustic properties.
Large- and small-diameter tube sections cover complementary frequency bands, allowing measurements across a wider range with appropriately sized specimens.
* The ZX9932 system consists of ZXONIC ZX8005 Signal Generator, ZX6500 Series DAQ System, and ZX8702 Power Amplifier, and is operated via the ZXONIC Dynamic Signal Analyzer (PC software) under the Impedance Tube Analysis module.
The hardware and software provide a workflow with of transfer-function calculation, result visualization, data export, and report generation.
Measurement Outputs (Normal Incidence)
Normal-incidence sound absorption coefficient, alpha
Normal-incidence pressure reflection coefficient, R (magnitude and phase)
Normal-incidence specific surface acoustic impedance, Zs
Normal-incidence specific surface acoustic admittance, Ys = 1/Zs
Transfer function, H12 (and related frequency-response results)