The LMS Test.Xpress Sound Intensity is a powerful tool for the determination of sound power levels according to ISO 9614 standard. Supporting both the scanning and the discrete point measurement techniques, the measurement sequence is tailored in the form of a step-by-step guided procedure.
The geometry of measurement surfaces is presented in a virtual “shoebox” configuration surrounding the test object. Each surface of the geometry can be segmented into the required subdivisions allowing measurements with finer spatial resolution. In support of the “discrete point” measurement technique, color coding scheme is applied to individual subdivision to visually guide the operator on areas that are assigned for the measurement, are measured or to be measured. For an efficient and effective definition of measurement functions, all related acquisition parameters are simplified and grouped into logical categories. To perform a valid measurement that complies with the ISO standard, sound intensity microphones/probe can be calibrated for amplitude calibration and Pressure Residual Intensity Index (PRII) calibration respectively. The Intensity is calculated from octave filters and/or in narrowband in a selectable frequency band up to 20kHz.
Direct measurement feedback is given in real-time through graphical 2D display as well as color-coded optical feedback that clearly indicates measurement status and ISO compliance. Critical results such as ISO field indicators (F1, F2, F3 and F4), calculated levels (sound power, sound intensity and pressure intensity) are presented in tabular format and corrective actions are suggested if the ISO criteria are not met. The results are available for individual measurement segment and per measurement surface, both as overall level and in frequency bands. The process is completed with detailed report in MS Excel and/or Word that contains all ISO required information.
Source localization is supported via a superimposed contour plot on the shoebox measurement surfaces allowing immediate detection of the noise source locations. One can add a picture (e.g. .jpg) behind the acoustical data to immediately relate the acoustics back to the internal structure of the measured object. The contour plot can present data in different octave fractions, narrowband with selectable bandwidth and centre frequency as well as overall values.
To ensure compliance with ISO measurement process and to minimize operator error, the complete procedure (from measurement to reporting) is fully automated and protected by a user-defined password. The automation tool allows test definition with specific measurement settings, preferred data visualization format, appropriate numerical functions for data analysis and a company/ISO style report.
