FFG

  • The project PASS, which is processed in cooperation with the IEW of the TU Vienna and psiacoustic GmbH, deals with the psychoacoustic evaluation of noise. The project is a continuation of the project RELSKG and deals with high and low noise barriers that are simulated with the 2.5 D boundary element method (BEM) assuming incoherent line sources. The comparison of the 2.5 D BEM with measurements resulted in a good agreement. Additionally measurements with rail dampers were taken into account in the psychoacoustic tests. The evaluation was done in two tests with 40 test persons. The first test determines the relative annoyance and the second the just noticeable difference in annoyance. The results ware that freight trains at the same A-level are less annoying than passenger trains and that at the same A-level the noise behind a noise barrier is a little bit more annoying than without a measure. The project started in 2013 and lasts until the end of 2014.

  • Objective

    We thank the Austrian Science Fund (FFG) for funding this project, grant number 873588. Principal Investigator is the AIT. Noise means trouble. In addition to traffic and industry, it is mainly emitted by heating or cooling appliances: Air heat pumps, recoolers and fans. In order to minimize noise immissions to the population in urban areas, the project is developing methods that enable simple, intuitive and at the same time accurate handling of noise emissions and their reduction.

     

    Methods

    The aim is to virtually place the noise sources in a real environment VOR ORT using augmented reality before they are installed and to visually display the sound emissions in colour and make them audible. Obstacles or soundproofing measures such as walls, fences and walls are detected automatically or can be added virtually. In order to achieve these goals, comprehensive method developments for efficient acoustic calculation are required: frequency-dependent and time-dependent behaviour, absorption and reflection. This unique approach facilitates the planning of renewable heating and cooling appliances, increases the acceptance and thus the share of renewable energies and lowers the noise level in cities.

     

     

     

     

     

  • Millions of people use headphones everyday for listening to music, for watching movies, or when communicating with others. Nevertheless, the sounds presented via headphones are usually perceived inside the head and not at their actual natural spatial position. This limited perception is inherent and results in unrealistic listening situations.

    When listening to a sound without headphones, the acoustic information of the sound source is modified by our head and our torso, an effect described by the head-related transfer functions (HRTFs). The shape of our ears contributes to that modification by filtering the sound depending on the source direction. But the ear is very listener-specific – its individuality is similar to that of a finger print, and thus HRTFs are very listener-specific. When listening to sounds via headphones, the listener-specific filtering is usually not available. One of the main reasons is the difficulty in the process of acquisition of the ear shape of a person, and thus in calculation of listener-specific HRTFs.

    Thus, in softpinna, we will work on the development of new methods for a better acquisition of listener-specific ear shapes of a person. Specifically, we will investigate and improve the so-called "non-rigid registration" (NRR) algorithms, applied on 3-D ear geometries calculated from 2-D photos of a person’s ears. The improvement in the quality of the 3-D ear geometries acquisition will allow computer programs to accurately calculate the listener-specific HRTFs, thus enabling the incorporation of listener-specific HRTFs in future headphone systems providing realistic presentation of spatial sounds. The new ear-shape acquisition method will vastly reduce the technical requirements for accurate calculation of listener-specific HRTFs.

    This project is done in collaboration with Dreamwaves GmbH. It is supported by the Bridge Programme of the FFG