On the formulation of the intensity method for determining sound reduction indices

Zyl, B. G. van; Erasmus, Pieter J.; Anderson, F.

doi:10.1016/0003-682x(87)90038-7

Cited by 11 publications

(10 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…One of the first publications in which the Waterhouse correction was applied in order to compare the traditional method with the intensity method was a paper by van Zyl et al published in 1987 [9]. Fairly good agreement between the two methods was obtained in a wide frequency range (from 100 Hz to 4 kHz).…”

Section: A Critical Review Of the Literature 21 Low Frequencies (50 mentioning

confidence: 99%

“…The intensity-based method of measuring transmission losses of partitions was introduced in the early 1980s as an alternative to the conventional method in which it must be assumed that the sound field in the receiving room is diffuse. Almost continuously since then, comparisons of conventional [1] and intensity-based [2] measurements of transmission loss have been described in the literature [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20].…”

Section: Introductionmentioning

confidence: 99%

“…Various authors [6,9] have pointed out that at low frequencies the well-known Waterhouse correction [21] should be used for the measurement in the receiving room in the traditional pressure-based method. However, in practice this correction is still only applied when the results are compared with results determined using the intensity method.…”

Section: Introductionmentioning

confidence: 99%

“…Reality, however, shows that in spite of all the improvements in the equipment and in our understanding of the methods, there seems to be systematic deviations between results determined with the conventional pressure-based method and results determined using sound intensity at both ends of the frequency range of interest, from 63 Hz to 6.3 kHz. Experimental results presented in references [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20] show, in general, very good agreement in the medium frequency range (250 Hz-3150 Hz), whereas one almost consistently finds that the intensity method gives lower values of the sound insulation than the conventional method in the lower end of the spectrum and higher values in the higher end of the spectrum.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Is There a Systematic Disagreement between Intensity-Based and Pressure-Based Sound Transmission Loss Measurements?

Machimbarrena¹,

Jacobsen

1999

Building Acoustics

View full text Add to dashboard Cite

Conventional and intensity-based sound transmission loss measurements have frequently been compared in the literature. Looking at published results determined under laboratory conditions, one would come to the conclusion that it is only possible to obtain good agreement between the two methods in a very restricted frequency range. It has often been reported that the intensity method gives lower values of the sound reduction index than the conventional method at low frequencies and higher at high frequencies. The purpose of this paper is to demonstrate with experimental data that excellent agreement between the two methods can be obtained in a fairly wide frequency range (80 Hz-6.3 kHz), provided that the measurements are carried out under optimum conditions. As pointed out by several authors, the only reason for systematic deviations between the two methods is the effect of having a partition that is highly absorbing in the receiving room.

show abstract

Section: A Critical Review Of the Literature 21 Low Frequencies (50 mentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Is There a Systematic Disagreement between Intensity-Based and Pressure-Based Sound Transmission Loss Measurements?

Machimbarrena¹,

Jacobsen

1999

Building Acoustics

View full text Add to dashboard Cite

show abstract

“…[1][2][3] The limitations of the new method have been examined in many connections. [4][5][6][7][8][9][10][11][12] The International Organization for Standardization ͑ISO͒ has published two standards concerning the new sound intensity technique, but has not yet published a special standard that could be applied to sound insulation measurements. 13,14 The reasons for this delay may be the small number of published results, and the complicated measurement procedures that are required compared to the conventional method, ISO 140-3.…”

Section: Introductionmentioning

confidence: 99%

Test procedure and automatic system for sound insulation measurement using the sound intensity method

Hongisto¹,

Nieminen²,

Koskela³

et al. 1997

Noise Control Eng. J.

View full text Add to dashboard Cite

A test procedure has been developed for sound insulation measurements using the sound intensity method. The basis of the procedure is from international standards ISO 140-3 and ISO 9614-1. For specimens that are sound absorbing on the receiving room side, the transmitted intensity will be underestimated if the extraneous sound intensity "caused by flanking or sound leaks… is high. A flanking ratio check is included in the test procedure to maintain accuracy within desired limits. The consideration of the field nonuniformity indicator, F 4 , in the test procedure was also found necessary. Seals at the edges of movable components of sound isolating structures, for example doors, are often poorly designed and manufactured. Sound leaks increase the value of the field indicator F 4 because of inhomogeneous sound transmission. Improving the seal of finished products is not possible in the test situation. For F 4 to fall in the acceptable range the number of measurement points may have to be increased enormously. The test procedure can be applied both to laboratory and field measurements. The main advantage of the new sound intensity method is the ability to locate sound leaks in the test object. This allows a customer-friendly mechanism for product development. Another advantage is that the laboratory facility can be much lighter than for the conventional method while maintaining the same limit for the maximum measurable sound reduction index. An automatic two-dimensional robot scanning system was used for exact positioning of the intensity probe. © 1997 Institute of Noise Control Engineering. †S0736-2501"97…00502-X ‡

show abstract

Sound transmission loss of glass and windows in laboratories with different room design

Cops

Soubrier

1988

Applied Acoustics

View full text Add to dashboard Cite

On the formulation of the intensity method for determining sound reduction indices

Cited by 11 publications

References 5 publications

Is There a Systematic Disagreement between Intensity-Based and Pressure-Based Sound Transmission Loss Measurements?

Is There a Systematic Disagreement between Intensity-Based and Pressure-Based Sound Transmission Loss Measurements?

Test procedure and automatic system for sound insulation measurement using the sound intensity method

Sound transmission loss of glass and windows in laboratories with different room design

Contact Info

Product

Resources

About