- Delta Acoustics & Vibration, Denmark
With an increase in the use of light building constructions, problems have arisen at low frequencies where these types of constructions unlike the traditional heavy constructions cannot provide sufficient sound insulation. The measurement methods of todays' building regulations do not consider frequencies below 100 Hz, and thus problems often appear in new buildings even when they comply with the demands in the normal frequency range. The purpose of the project is to evaluate the annoyance caused by a change in the low frequency level below 100 Hz by the use of subjective listening test. Frequency filters for five construction types, ranging from light to heavy constructions, have been created and applied to sound examples of three types of noise, two of impact noise and one of airborne noise. The presentations represented building constructions that would produce the same measurement results with the normal methods, although the A-weighted levels were different. Listening test were carried out with 25 test subjects, each of whom evaluated 24 presentations twice. The experiments have shown that an increase in the level at low frequencies produces greater annoyance, and thus it can be concluded that the traditional measurement methods are no longer adequate and a revision should be considered. One of the conclusions was that female subjects appeared to be much more annoyed by noise than male subjects.
|Period||01/11/97 → 30/04/99|
|Amount||979,000.00 Danish kroner|