This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
Verification of a Miniature Reverberation Room for Sound Absorption Measurements Using Corner Microphone Technique
Annotation ability available
Sector:
Language:
English
Abstract
The paper reports the results of sound absorption verification studies of a rectangular parallelepiped reverberation room that is a dimensionally scaled (miniature) version of a full-size, reference reverberation room. The qualification procedure compares the measurement results obtained in the miniature (mini-verb) room with that determined for the same sample in the reference room, where traditional pressure microphone techniques and decay measurements are employed.
The absorption measurements in the mini-verb room, however, are based upon a new technique which relies upon the use of boundary microphones installed in very close proximity to each intersection of three room boundaries (i.e., the eight (8) trihedral corners). An array of boundary microphones, one in each corner, is used in place of a traditional spaced array of pressure microphones, or of a single moving microphone.
The results of this work demonstrate that the corner microphone technique allows sound absorption measurements within the mini-verb room to compare favorably to results in the reference room, while also allowing several advantages over traditional microphone approaches. Verification studies show that the measurement uncertainty of absorption data is influenced by the number of stationary sound diffusers within the mini-verb room, and that the number and locations of these diffusers strongly influences the degree to which mini-verb room absorption results agree with results in the reference room.
Recommended Content
Authors
Topic
Citation
Kolano, R. and Kleckner, J., "Verification of a Miniature Reverberation Room for Sound Absorption Measurements Using Corner Microphone Technique," SAE Technical Paper 971895, 1997, https://doi.org/10.4271/971895.Also In
References
- Chappuis Andre Interkeller AG. Smaller Size Devices for Accurate Acoustical Measurements of Materials and Parts used in Automobiles SAE Proceedings, Paper 93126 15 25
- Pallett D. S. Pierce E. T. Toth D. D. A Small-Scale Multi-Purpose Reverberation Room Applied Acoustics 1976 Applied Science Publishers Ltd. England
- Kolano Richard A. P.E. Beggs William S Saha Pranab Ph.D., P.E. Automotive Testing Requirements in the Design of a Reverberation Chamber SAE Technical Paper No. 931290 SAE Noise and Vibration Conference Traverse City, MI May 1993
- Nwankwo Oliver O. Szary Marek L. Calibrating Reverberation Room for Accurate Material Sound Absorption Measurements SAE International, Paper 960191
- American Standards for Testing and Materials (ASTM) Designation C423-90a Standard Test Method for Sound Absorption and Sound Absorption Coefficients by the Reverberation Room Method
- Kolano Richard A. P.E. Corner Mounted Boundary Microphones for Measuring Decay Rate in a Reverberation Room Noise-Con 94 Ft. Lauderdale Fla May 1994