Effect of sound absorption and screen height on spatial decay of speech – Experimental study in an open-plan office

This report deals with a theoretical and experimental study of the low frequency sound absorption characteristics of perforated honeycomb sandwich panels. The derivations of formulae for absorption in terms of double perforation ratio and air gap are presented. Results show that the honeycomb absorber, with double perforated sheets, can be an effective low frequency absorber for frequencies down to 63 Hz. In addition, honeycomb panels have advantages over other low frequency absorbers in that they are light weight and strong.

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Experimental Study on the Sound-Absorption Capability of Nonwoven Sound-Absorbing Material under Different Density Combination

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.332-334.1304 ◽

2011 ◽

Vol 332-334 ◽

pp. 1304-1307

Author(s):

Wen Su ◽

Xiao Ming Qian ◽

Xin Yu Li ◽

Shu Sen Liu

Keyword(s):

Experimental Study ◽

Sound Absorption ◽

Low Density ◽

Surface Material ◽

Nonwoven Materials ◽

Absorbing Material

In this paper, the influence of different combination of different density of nonwoven materials on the sound-absorption capability is studied through the serial experiments. The results show that the structure with low density on the surface material and dense density in the middle of the material will have better capacity in absorbing sound.

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Crumb Rubber Effect on Acoustic Properties of Self- Consolidating Concrete

International Journal of Thermal and Environmental Engineering ◽

10.5383/ijtee.08.02.002 ◽

2014 ◽

Vol 08 (2) ◽

Keyword(s):

Experimental Study ◽

Noise Reduction ◽

Sound Absorption ◽

Crumb Rubber ◽

The Self ◽

Acoustic Properties ◽

Scrap Tires ◽

Self Consolidating Concrete ◽

Reduction Coefficient ◽

Environmentally Sound

Several researches have been conducted to find a practical and environmentally sound solution of the problem of scrap tires. In this context, an experimental study was conducted to provide more data on the effect of crumb rubber on the acoustic properties of self-consolidating concrete SCC. To this end, Parallelepiped and cylindrical specimens were prepared by varying the proportion of crumb rubber with percentages of 0 %, 10 %, 20 % and 30 % of the volume of gravel. Properties such standardized level difference, sound absorption at different frequency and noise reduction were investigated. The results showed that the sound absorption and noise reduction coefficient were increased according to the increase of the percentage of crumb rubber. The self-consolidating concrete rubber SCCR has better acoustic properties in comparison with SCC.

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Experimental study on the acoustic field caused by the interference of supersonic jet with a perforated plate—The optical measurement of sound absorption

The Journal of the Acoustical Society of America ◽

10.1121/1.5137387 ◽

2019 ◽

Vol 146 (4) ◽

pp. 3000-3000

Author(s):

Yo Murata ◽

Kaku Murayama ◽

Tatsuya Ishii ◽

Koji Okamoto ◽

Hirofumi Daiguji ◽

...

Keyword(s):

Experimental Study ◽

Acoustic Field ◽

Sound Absorption ◽

Optical Measurement ◽

Supersonic Jet ◽

Perforated Plate

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Influence of Sound-Absorbing Material Placement on Room Acoustical Parameters

Acoustics ◽

10.3390/acoustics1030038 ◽

2019 ◽

Vol 1 (3) ◽

pp. 644-660 ◽

Cited By ~ 1

Author(s):

Jose Cucharero ◽

Tuomas Hänninen ◽

Tapio Lokki

Keyword(s):

Speech Intelligibility ◽

Sound Absorption ◽

Sound Field ◽

Acoustical Parameters ◽

Open Plan ◽

Absorbing Material ◽

The Impact

The reverberation of a room is often controlled by installing sound absorption panels to the ceiling and on the walls. The reduced reverberation is particularly important in classrooms to maximize the speech intelligibility and in open-plan offices to make spaces more pleasant. In this study, the impact of the placement of the absorption material in a room was measured in a reverberation room and in a mockup classroom. The results show that absorption material is less efficient if it is mounted to the corners or on the edges between the walls and ceiling, if the sound field is more or less diffuse. If the room modes dominate the sound field, the most efficient location for the sound-absorbing material was found at one of the surfaces causing the modes. The results help acoustical consultants to place the absorption material in optimal locations and, generally, minimize the amount of material and save costs.

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