2444, rue Bonin Sherbrooke, J1K 1C4, Canada

(819) 346-5666 info@mecanum.com

Impedance and Transmission Tubes

 

Mecanum’s impedance and transmission tubes are specifically designed to measure the main acoustic indicators of a wide range of acoustical materials. The method is based on ASTM E1050, ISO 10534-2 and ASTM E2611 standards.

 

 

 

Material Properties

➡ Normal incidence sound absorption coefficient (α)

➡ Normal incidence complex reflection coefficient (R)

➡ Normal surface impedance (Zs)

➡ Normal incidence sound transmission loss (TL)

➡ Characteristic impedance (Z)

➡ Wave number (k)

➡ Transfer matrix coefficients (Tij)

➡ Equivalent/effective dynamic density (ρeq)

➡ Equivalent/effective dynamic bulk modulus or compressibility (Keq)

Tube Models

Impedance Tube (2 microphones)
Available options: 29 mm diameter (200-6600 Hz), 44.44 mm diameter (100-4300 Hz), 100 mm diameter (35-1900 Hz)

Impedance and Transmission Tube (3 microphones)
Available options: 29 mm diameter (200-6600 Hz), 44.44 mm diameter (100-4300 Hz), 100 mm diameter (35-1900 Hz)

Impedance and Transmission Tube (4 microphones)
Available options: 29 mm diameter (200-6600 Hz), 44.44 mm diameter (100-4300 Hz), 100 mm diameter (35-1900 Hz)

Portable High Sound Pressure Level Impedance Tube (2 microphones)
High SPL 19 mm diameter (500-10000 Hz, 155 dB), 29 mm diameter (500-6600 Hz, 155 dB)

Applications

  • Benchmarking
  • Quality control
  • R&D applications

Impedance and transmission measurements can be used by FOAM-X for the inverse identification of open cell porous material properties such as : open porosity, static airflow resistivity, tortuosity, viscous and thermal characteristic lengths, and static thermal permeability.

Features

Standard Mecanum’s impedance and transmission tube system includes:

  • Impedance and transmission tube;
  • Microphones;
  • DAQ system;
  • Ultralow distortion audio amplifier;
  • TUBE-X software;
  • A verification sample to check the measurement procedure;
  • Grids to support limp materials;
  • Rings to minimize acoustical leaks around the sample.

TUBE-X software fully controls the measurement procedure from the calibration to the measurement itself.  It corrects the atmospheric conditions and the tube’s internal dissipation.  It may also eliminate effects of grids and rings if they are used during measurement. Small (29-mm diameter), medium (44.44-mm diameter), large (100-mm diameter), and custom (circular or rectangular) tubes are also available to cover respectively the 200-6600 Hz, 100-4300 Hz, 35-1900 Hz, and custom frequency ranges.

VIDEO

 Other Mecanum’s Related Products

➡ Grids and rings

 Verification and calibration samples

 Porous material slicer

 Circular cutter

 Resistive screen and fabric holder

 Enviro Weather station

 Three-microphone version upgrade

➡ NOVA

➡ FOAM-X

More Information

➡ Download Flyer

➡ Information and Price