In various surveys, it was found that people living in multi-family dwellings and apartment houses are annoyed by noise of their neighbors. Also, it seems that building regulations, for example, the German standard DIN 4109 “Sound insulation in buildings,” are insufficient. The degree of annoyance is influenced by the personal conditions of the habitants (stress), the value of the dwelling and the duration the habitants live there. The effects on humans include disturbance of conversation or listening to the TV or radio in private dwellings as well as communication in office premises, reduced power of concentration during physical or mental work, and disturbance of sleep. All this strongly depends on the kind of noise signal (speech, music, footfall, etc.) and on the context, and thus, it is highly doubtful if single-number quantities such as the STL sufficiently describe the real situation. In this paper, a technique is presented for auralization of complex virtual acoustic scenes including airborne and structure-borne noise in buildings with particular respect to sound propagation across or between coupled rooms. Based on SEA-like sound propagation models in standardized prediction methods (EN 12354), algorithms are designed for FIR filtering of audio signals and applied in listening tests and for to creation of audio demos. The auralized sounds can be used during building design processes, in studies of human noise perception, and in development of new metrics for future building codes.

Four of the nine big Technical Universities in Germany, together with Chalmers University of Technology in Sweden, have developed a new Massive Open Online Course (MOOC) on the subject of Communication Acoustics. The idea is to foster education on the late Bachelor or early Master level by joining the expertise available at individual universities and by creating an online course offered both to local as well as remote students. The course started in winter term 2016 and is hosted on the EdX platform. It is offered in English language and roughly divided into two parts: The first part covers basics on acoustics, signal processing, human hearing, speech production, as well as electroacoustics and psychoacoustics. The second part introduces selected applications, such as sound recording and reproduction, sound fields and room acoustics, binaural technology, speech technology, as well as product sound design. The course material consists of explanatory videos and text as well as audiovisual material, exercises, and self-assessments. The final examination takes place as a written or online exam, with physical presence at the contributing sites. The talk will provide insights into the experiences we made, and illustrates how we overcame the obstacles inherent to cross-university education.

The issue of aircraft noise experienced by residents in the airport's neighborhoods is one of subjective annoyance and a presentation of noise intensity in decibels alone might not be sufficient to give a clear understanding of noise abatement measures being carried out or the effect for instance of constructing a new runway at an airport. Although noise contours can be a great way of a quick assessment of noise impact over larger areas, noise quantified in numbers can prove lacking in capturing the actual annoyance caused by the noise to the residents. For this reason, a method providing a more subjective assessment of aircraft noise impact is required and auralization of complete aircraft movements could be one such way of better capturing the annoyance due to noise caused by aircraft. The Virtual Air Traffic System Simulation (VATSS) interdisciplinary project of RWTH Aachen University has the aim of presenting the effect of complete aircraft movements via visualization and auralization of aircraft noise in 3-D Virtual Reality environments for the subjective assessment of aircraft noise. This paper focusses on the interdisciplinary collaboration of the Institute of Aerospace Systems and the Institute of Technical Acoustics of RWTHAachen to produce a capability of auralizing complete time-dependent take-off and landing procedures up to an altitude of 3000 meters. The noise produced by a conventional aircraft with a turbofan engine is modeled and the ILR's capability to model aircraft noise for complete 4-D take-off and landing procedures is shown along with the technique to auralize complete standard procedures as well as noise abatement procedures with time-varying settings. Both broadband and tonal noise components for dominant sources are auralized for the movements. Nomenclature t e = emission time t reception = reception time t delay = time delay c = speed of sound h = aircraft altitude s source-obs = straight path distance between aircraft and observer f = frequency/harmonic frequency 2 B = number of fan rotor blades M = Mach number θ = polar directivity angle φ = phase v i = i th voxel (cuboid volume element) s = distance D = atmospheric attenuation

With the aim to reduce the necessary efforts to empirically determine the uncertainty in room acoustical measurements, in previous work, a model was developed that can predict the uncertainty a directivity of a sound source introduces to a measurement. As part of the validation extensive series of scale measurements have been conducted. In this contribution, the predicted uncertainty based on simulations and the empiric data is compared to each other. The results were used to improve the model. Concluding it will be discussed whether the model is suitable for a reasonable measurement uncertainty discussion.

For evaluating the performance of room acoustical simulations or numerical simulations in general, these are usually compared to corresponding measurements as a benchmark. Previous studies indicated that differences may result from neglecting wave effects (scattering, diffraction, attenuation at grazing incidence). However, it also proved to be a challenge to provide a precise representation of the primary and secondary structure (geometry, source and receiver characteristics, absorption and scattering coefficients) of the measured ground truth to be re-modeled in the simulation. The round robin on auralization aimed to overcome such shortcomings by generating a ground truth database of room acoustical environments provided to developers of room simulation software. The database includes a selection of acoustic scenes such as “single reflection,” or “coupled rooms” which isolate single acoustic phenomena, as well as three complex “real-world” environments of different size. Simulated monaural and binaural impulse responses were evaluated by comparing them to the corresponding measurements on the basis of acoustical parameters as well as perceptual qualities. We introduce the concept of the round robin along with the description of the acoustic scenes, the acquisition of monaural and binaural impulse responses, and the identification of the boundary conditions.