Comparison Failure and Successful Methodologies for Diffusion Measurements Undertaken inside Two Different Testing Rooms
The scattering phenomenon is known to be of great importance for the acoustic quality of a performance arts space. The scattering of sound can be achieved in different ways: it can be obtained by the presence of architectural and/or decorating elements inside a room (e.g., columns, statues), by the...
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| Format: | Article |
| Language: | English |
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MDPI AG
2021-11-01
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| Series: | Applied Sciences |
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| Online Access: | https://www.mdpi.com/2076-3417/11/22/10523 |
| _version_ | 1827677530821230592 |
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| author | Lamberto Tronchin Angelo Farina Antonella Bevilacqua Francesca Merli Pietro Fiumana |
| author_facet | Lamberto Tronchin Angelo Farina Antonella Bevilacqua Francesca Merli Pietro Fiumana |
| author_sort | Lamberto Tronchin |
| collection | DOAJ |
| description | The scattering phenomenon is known to be of great importance for the acoustic quality of a performance arts space. The scattering of sound can be achieved in different ways: it can be obtained by the presence of architectural and/or decorating elements inside a room (e.g., columns, statues), by the geometry and roughness of a surface (e.g., Quadratic Residue Diffuser (QRD)) and by the diffraction effect occurring when a sound wave hits the edges of an obstacle. This article deals with the surface scattering effects and the diffusion phenomenon only related to MDF and plywood panels tested by disposing the wells both horizontally and vertically. The test results undertaken inside a semi-reverberant room and inside a large reverberant room have been compared to highlight the success and the failure of the measuring methodologies. In detail, according to the existing standards and regulations (i.e., ISO 17497—Part 2), diffusion measurements have been undertaken on a few selected types of panel: two QRD panels (made of Medium Density Fiberboard (MDF) and plywood) with and without a smooth painted solid wood placed behind the QRD. The panels have been tested inside two rooms of different characteristics: a semi-anechoic chamber (Room A) and a large reverberant room (Room B). The volume size influenced the results that have been analyzed for both chambers, showing an overlap of reflections on panels tested inside Room A and a clear diffusion response for the panels tested inside Room B. In terms of the diffusion coefficient in all the octave bands between 125 Hz and 8 kHz, results should not be considered valid for panels tested in Room A because they were negatively impacted by extraneous reflections, while they are reliable for panels tested in Room B. |
| first_indexed | 2024-03-10T05:45:17Z |
| format | Article |
| id | doaj.art-8d3d0874073643cab87225481e35c12d |
| institution | Directory Open Access Journal |
| issn | 2076-3417 |
| language | English |
| last_indexed | 2024-03-10T05:45:17Z |
| publishDate | 2021-11-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Applied Sciences |
| spelling | doaj.art-8d3d0874073643cab87225481e35c12d2023-11-22T22:15:00ZengMDPI AGApplied Sciences2076-34172021-11-0111221052310.3390/app112210523Comparison Failure and Successful Methodologies for Diffusion Measurements Undertaken inside Two Different Testing RoomsLamberto Tronchin0Angelo Farina1Antonella Bevilacqua2Francesca Merli3Pietro Fiumana4Department of Architecture, University of Bologna, 47521 Cesena, ItalyDepartment of Industrial Engineering, University of Parma, 43124 Parma, ItalyDepartment of Industrial Engineering, University of Parma, 43124 Parma, ItalyCIRI-Interdepartmental Centre for Industrial Research in Building and Construction, University of Bologna, 40132 Bologna, ItalyTechno Srl, Via Pirano 7, 48122 Ravenna, ItalyThe scattering phenomenon is known to be of great importance for the acoustic quality of a performance arts space. The scattering of sound can be achieved in different ways: it can be obtained by the presence of architectural and/or decorating elements inside a room (e.g., columns, statues), by the geometry and roughness of a surface (e.g., Quadratic Residue Diffuser (QRD)) and by the diffraction effect occurring when a sound wave hits the edges of an obstacle. This article deals with the surface scattering effects and the diffusion phenomenon only related to MDF and plywood panels tested by disposing the wells both horizontally and vertically. The test results undertaken inside a semi-reverberant room and inside a large reverberant room have been compared to highlight the success and the failure of the measuring methodologies. In detail, according to the existing standards and regulations (i.e., ISO 17497—Part 2), diffusion measurements have been undertaken on a few selected types of panel: two QRD panels (made of Medium Density Fiberboard (MDF) and plywood) with and without a smooth painted solid wood placed behind the QRD. The panels have been tested inside two rooms of different characteristics: a semi-anechoic chamber (Room A) and a large reverberant room (Room B). The volume size influenced the results that have been analyzed for both chambers, showing an overlap of reflections on panels tested inside Room A and a clear diffusion response for the panels tested inside Room B. In terms of the diffusion coefficient in all the octave bands between 125 Hz and 8 kHz, results should not be considered valid for panels tested in Room A because they were negatively impacted by extraneous reflections, while they are reliable for panels tested in Room B.https://www.mdpi.com/2076-3417/11/22/10523scattering effectdiffusion coefficientreflecting panelsQRDISO 17497 |
| spellingShingle | Lamberto Tronchin Angelo Farina Antonella Bevilacqua Francesca Merli Pietro Fiumana Comparison Failure and Successful Methodologies for Diffusion Measurements Undertaken inside Two Different Testing Rooms Applied Sciences scattering effect diffusion coefficient reflecting panels QRD ISO 17497 |
| title | Comparison Failure and Successful Methodologies for Diffusion Measurements Undertaken inside Two Different Testing Rooms |
| title_full | Comparison Failure and Successful Methodologies for Diffusion Measurements Undertaken inside Two Different Testing Rooms |
| title_fullStr | Comparison Failure and Successful Methodologies for Diffusion Measurements Undertaken inside Two Different Testing Rooms |
| title_full_unstemmed | Comparison Failure and Successful Methodologies for Diffusion Measurements Undertaken inside Two Different Testing Rooms |
| title_short | Comparison Failure and Successful Methodologies for Diffusion Measurements Undertaken inside Two Different Testing Rooms |
| title_sort | comparison failure and successful methodologies for diffusion measurements undertaken inside two different testing rooms |
| topic | scattering effect diffusion coefficient reflecting panels QRD ISO 17497 |
| url | https://www.mdpi.com/2076-3417/11/22/10523 |
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