A sonic crystal barrier, consisting of empty micro-perforated cylindrical shells, was built on the campus at the Universitat Politècnica de València in 2011 and characterised by using a non-standardised measurement technique. In this paper, the sonic crystal barrier, upgraded with rubber crumb inside the micro-perforated cylindrical shells, was characterised by using standardised measurement techniques according to EN 1793-5 and EN 1793-6. As a result of the characterisation, sound insulation properties of the barrier were shown to be a combination of the absorptive properties of the individual building units and the reflective properties of their periodic distribution. In addition, its performance was compared with a similar barrier consisting of rigid polyvinyl chloride (PVC) cylinders, which was recently characterised using the same standardised techniques. In comparison with the barrier based on PVC cylinders, the barrier investigated here produced a broadband enhancement of the sound insulation and lower reflection indices in the targeted frequency range. It was also shown that the influence of leakage under the barrier and the width of the temporal window on sound insulation was negligible. While EN 1793-5 and 1793-6 allow a direct comparison of the performance of different noise barriers, the applicability to this new type of barriers requires further investigation.

Public entertainment premises are significant sources of urban noise pollution. In this paper, indoor sound level spectra for different types of entertainment premises have been analyzed. While most of the spectra lie between two standardized curves proposed by the ISO 717-1:2013 (The International Organization for Standardization) standard, spectra recorded in discotheques show a pronounced spectral level below 160 Hz as a result of an intensive use of subwoofers. This indicates potentially inappropriate rating of sound insulation against such specific low-frequency noise by standardized spectrum adaptation terms. A modified spectrum adaptation term for a single-number rating of sound insulation under such circumstances has been proposed.

Sadržaj -Standard ISO 18233 definiše nove metode merenja u gra evinskoj akustici i akustici prostorija zasnovane na deterministi kim pobudnim signalima. Prema ovom standardu predložene metode obezbe uju ve i odnos signal -šum u pore enju sa klasi nom metodom (ISO 140), u kojoj se kao pobudni signal koristi slu ajni šum. U ovom radu su prikazani rezultati merenja nivoa zvuka u prostoriji dobijenih klasi nom i swept-sine metodom. Rezultati pokazuju da se obe metode mogu koristiti za pomenutu namenu i van laboratorijskih uslova. Oni još ukazuju i na mogu nost dobijanja korektnih rezultata novom metodom, ali uz adekvatnu kalibraciju.Klju ne re i -impulsni odziv, nivo zvuka, swept-sine.