Projects Archives


Schallabsorption von Wandpanel-Unikaten
Es wurden schallabsorbierende Wandpaneele entwickelt, welche massgeschneidert in den Kontext der Raumarchitektur und der Ästhetik eingepasst werden können - individuell entworfen und produziert (handgewoben). Dabei konnte eine hohe Schallabsorption erreicht werden, und es zeigte sich, dass unter Einhaltung von Regeln die handgewobenen Stoffe zu einer für die Praxis vernachlässigbaren Streuung der Absorptionswerte führen.
Kontakt: Kurt Eggenschwiler
Finanzierung: Innovationsscheck
Laufzeit: 2019 - 2020

BiMeWAVES aims to develop a new class of innovative materials capable of controlling acoustic and elastic waves by adapting the concept of hierarchical structure derived from biological systems to a new class of artificially engineered media, i.e. the so-called elastic Metamaterials (MMs).
The project integrates inter-disciplinary aspects such as: (1) biological inspiration driving the (2) design, manufacturing and optimization of innovative materials guiding the conclusive (3) proof-of-concept experiments aimed at providing the society with novel applicative tools in diverse technological fields, ranging from noise abatement to non-destructive evaluation and underwater acoustics.
Contact: Armin Zemp
Funding: Marie Curie COFUND
Duration: 2018 – 2020


Validation of the aircraft noise simulation model sonAIR
Validation of the aircraft noise simulation model sonAIR based on measurement data, which was not used in the model development. To that purpose also measurement data from external partners will be used. In addition some open issues of the initial project phase will be studied in more detail.  
Contact: Jean Marc Wunderli
Partner: Swiss International Airlines, DLR, TU Delft
Project funding: FOCA
Duration: 2017 – 2018

Estimation of flight parameters based on radar data
Besides position, orientation and speed, the sonAIR sound source models also needs information on thrust setting and configuration as input parameters. However this information is generally not available. Therefore methods shall be developed on how to estimate aircraft mass, thrust setting and configuration based on radar data. On that basis the range of applications of sonAIR can be substantially extended and will allow to calculate entire airport scenarios in the future.
Contact: Jean Marc Wunderli
Partner: Swiss International Airlines
Project funding: FOCA
Duration: 2017 – 2018

Development and operation of a monitoring system for aircraft noise for the specific demands of sonAIR
In this project a mobile monitoring system together with an automized analysis system shall be developed with the goal of regularly updating the emission database of sonAIR. The monitoring system shall then be used to derive sound source models for recently introduced and modified aircraft types of Swiss International Airlines, such as Bombardier C-Series, Boeing B777 and the modified Airbus A320-family.
Contact: Jean Marc Wunderli
Partner: Swiss International Airlines, skyguide
Project funding: FOCA
Duration: 2017 – 2019

Towards Noise and Weight Reduction by Application of FRP Wheelsets for Freight Wagons
Fiber-reinforced polymer (FRP) composite materials shall be used to manufacture a train wheelset which will generate less noise and leads to a significant weight reduction of the wheelset. The technical feasibility is verified in this project in collaboration with our partners.
Contact: Armin Zemp
Partners: Laboratory for Structural Engineering (Empa), Carbo-Link, PROSE AG
Funding: FOEN
Duration: 2017 – 2018

IDeAL (Impact Driven Assessment of novel Low-noise aircraft concepts) Pilot study
The goal of the IDeAL project is to optimize novel low-noise aircraft concepts and alternative flight procedures with respect to human perception and annoyance.  
The simulation and development of aircraft concepts and flight procedures is done by the German Aerospace Centre (DLR). Its results provide the necessary inputs for auralizations done by Empa. Based on listening tests perceived loudness and annoyance shall be evaluated and used as a feedback-loop to optimize the design. In this pilot study a proof of concept, an identification of open research questions as well as an assessment of the existing optimization potential shall be accomplished.
Contact: Reto Pieren
Project partners: DLR
Project funding: BAFU
Duration: 2017 – 2018
Available Publication

Under the umbrella of the European Shift2Rail initiative to support research and innovation in rail product solutions, the project DESTINATE aims to develop tools and methodologies for railway noise simulation and cost-benefit analysis of mitigation actions of interior and exterior noise. Empa is involved in the auralisation and visualization of noise mitigation measures with the goal to more accurately predict peoples response to exterior noise from a residents perspective and to interior noise from a passengers perspective.
Contact: Kurt Heutschi
Project partners: Technische Universität Berlin (Coordinator), TUB, Germany, Politechnika Poznańska, PUT, Poland, University of Newcastle upon Tyne, UNEW, UK, Müller-BBM GmbH, MBBM, Germany, Sound Advice in Technology, Innovation and Strategy, SATIS, The Netherlands, Stadler Rail Valencia, STAV, Spain, Netherlands Aerospace Centre, NLR, The Netherlands
Project funding: EU Horizon 2020
Duration: 2016-2018
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Coating of freight wagons for noise mitigation
The goal of this project is to assess the effectiveness of a coating applied to freight wagons for noise mitigation. Besides the sensitivity of the coating material to wear, the impact on the vibratory response of the silo before and after coating as well as the reduction of the noise emission during loading and draining of gravel are experimentally investigated.
Contact: Armin Zemp
Project Partner: Josef Meyer Rail
Project Funding: FOEN
Duration: 2016 - 2017

The Sound of Brass: The Materiality, acoustics and history of brass instruments, based on the example of historically informed replica of German trombones
How were early brass instruments constructed, and of what? If we build copies using historic manufacturing techniques, what impact does this have on their playing characteristics and their sound? And can we measure this?
Many questions on the materiality and the production technology of historical brass instruments remain unanswered today. This project is intended to use reconstructions of the legendary German trombones of the 19th and early 20th centuries to reacquire the techniques of historical craftsmen. The acousticians of Empa are investigating their influence on the playing characteristics and on the radiated sound. The reconstructions of German orchestral trombones built in the course of this applied research will ultimately be presented in concert.
Contact: Armin Zemp
Project Funding: CTI
Duration: 2015–2018


The goal of the project OST is the development of tool to simulate railway rolling noise. The different steps from the excitation mechanisms to vibration propagation to sound radiation and propagation shall be modelled as close to physics as possible. The tool shall be used in a later step to develop acoustically optimized track constructions. The project is financed by FOEN and FOT and is conducted in collaboration with the technical universities of Berlin and Munich.
Contact: Jean Marc Wunderli
Project partner: TU Berlin, TU München
Project funding: BAV, FOEN
Duration: 2015 - 2017

Listening tests to assess the annoyance of helicopter noise compared to wing-mounted propeller driven aircraft
Listening tests are performed in the lab to determine the annoyance rating of helicopters and wing-mounted propeller driven aircraft in different procedures (take-off, landing, cruise). On this basis a source-specific level correction relative to the A-weighted sound exposure level (LAE) shall be deduced for small aircraft.
Contact: Beat Schäffer
Project funding: FOEN
Duration: 2016 - 2017


Participation in the interdisciplinary project SiRENE (Short and Long Term Effects of Traffic Noise Exposure), which investigates acute, short- and long-term effects of road, railway and aircraft noise exposure on annoyance, sleep disturbances and cardiometabolic risk. SiRENE is funded by SNF-Sinergia and is supported by the Federal Noise Abatement Commission EKLB as well as the Federal Office for the Environment FOEN.
Contact: Jean Marc Wunderli
Project partner: Uni Basel, Swiss TPH, n-Sphere, FOEN
Project funding: SNF, FOEN
Duration: 2013 - 2016

In the SiRENE project a nationwide assessment of road, railway and aircraft noise exposure was conducted and a socio-acoustic study with 5600 participants was performed. SIAS is a follow-up study in which interviews with about 100 participants of the SiRENE study are carried out at their homes to elucidate – among others – the role of open windows for the well-being of the inhabitants. On that occasion on the one hand short-term measurements are performed to determine the inside-outside level difference for different window positions (closed, tilted, open). On the other hand sound-level meters are flush mounted on the outer face of the closed window to record A-weighted equivalent sound pressure levels in a temporal resolution of 1 s during one week. The first measurements are used to establish a model for inside-outside level differences, the second to validate the exposure modelling of SiRENE.
Contact: Jean Marc Wunderli
Project partner: Swiss Tropical and Public Health Institute, Basel; n-Sphere, Zürich.Project funding: FOEN
Duration: 2016 - 2017

Neue Untersuchungen zum Messverfahren zur Simulation haustechnischer Benutzungsgeräusche mit dem Pendelfallhammer gemäss Schweizer Norm SIA 181 „Schallschutz im Hochbau"
Mit der Neufassung der Schweizer Norm SIA 181 „Schallschutz im Hochbau“ im Jahr 2006 wurde ein Messverfahren zur Simulation von Benutzergeräuschen bei Badewannen, Duschwannen, Waschbecken etc. mit einem Pendelfallhammer eingeführt. Trotz den nicht bezweifelten Vorteilen der Messmethode tauchten in den letzten Jahren vermehrt Fragen zu verschiedenen Problemstellungen auf. Die Eigen-schaften des Pendelfallhammers sind in der Norm nur unzureichend spezifiziert und es mangelt an ei-nem Verfahren, um diese periodisch zu überprüfen. Das Messverfahren ist zu wenig detailliert be-schrieben, so dass sich z.B. je nach Wahl der Anregungspunkte unter Umständen sehr unterschiedliche Resultate ergeben können. Es werden auch keine Angaben zur Messunsicherheit gemacht. Die Norm gibt  für verschiedene Anregungssituationen Korrekturpegel zur Berücksichtigung der Unterschiede zwischen dem Pegel der Originalgeräusche und dem mit dem Pendelfallhammer erzeugten. Diese Kor-rekturwerte werden zum Teil in Frage gestellt. Zudem wird behauptet, dass der durch Schallabstrahlung vom untersuchten Bauteil übertragene Luftschallanteil, je nach baulicher Situation, zu hoch sei und das Messergebnis verfälschen kann. Im Projekt werden die Fragen geklärt und ein Input zur Revision der Norm SIA 181 geleistet.

Ansprechpartner: Kurt Eggenschwiler
Projektförderung: suissetec, BAFU
Projektdauer: 2017-2018


Annoyance caused by wind turbine compared to road traffic noise
On behalf of FOEN listening tests are performed in collaboration with the Catholic University of Eichstätt-Ingolstadt (D) in which participants rate the annoyance caused by different acoustic situations of wind turbine and road traffic noise. With these tests, the (increased) noise annoyance caused by wind turbine compared to road traffic noise can be investigated and quantified. In addition, in a separate experiment special acoustic characteristics of wind turbines are investigated which can influence noise annoyance (e.g., amplitude modulation).

Contact: Beat Schäffer
Project funding: FOEN
Duration: 2014 - 2016

In the frame of the Eureka project Ecovehicle, methods to identify and promote environmentally friendly road and rail vehicles are developed together with foreign partners. The work of the Swiss project team: Empa labs Road Engineering / Sealing Components, Automotive Powertrain Technologies and Acoustics / Noise Control and Quantis is funded by Bafu, ASTRA and ARE.
Contact: Kurt Heutschi
Project partner: Empa, Road Engineering / Sealing Components Laboratory, Empa, Automotive Powertrain Technologies, Sciotech Projects, UK, TDC Systems, UK, SVUM, CZ, Kistler, CH
Project funding: FOEN
Duration: 2014 - 2017

On behalf of Bafu the existing road traffic noise emission model is updated. The model will fit to the properties of the new vehicle fleet and will allow for investigating in greater detail parameters that influence noise emission.
Contact: Kurt Heutschi
Project funding: FOEN
Duration: 2015 - 2017


Within the framework of the sonAIR project we are developing a new calculation model with which low-noise landing and take-off procedures can be computationally validated and acoustically optimized.
Contact: Jean Marc Wunderli
Project partner: n-Sphere, BeSB, SciTracks
Project funding: FOCA, FOEN, Canton of Zurich, airports Zurich and Geneva, skyguide
Duration: 2013 - 2016

Development and maintenance of the shooting noise model sonARMS.
Contact: Jean Marc Wunderli
Project funding: FOEN, Canton of Zurich, Canton of Graubünden
Duration: 2012 - 2016

In the Marie-Curie project SONORUS early stage researchers are educated as “Urban Sound Planers”. In the context of this project a tool to auralise aircraft noise will be developed.
Contact: Kurt Heutschi
Project partner: Chalmers Tekniska Högskola, Chalmers, Sweden, Eindhoven University of Technology, TUe, The Netherlands, Seconda Università degli Studi di Napoli, SUN, Italy, The University of Sheffield, USFD, UK, Ghent University, UGENT, Belgium, Müller-BBM, MBBM, Germany, The Italian National Institute for Environmental Protection and Research, ISPRA, Italy, SP Technical Research Institute of Sweden
Project funding: EU Marie Curie
Duration: 2012 - 2016

Automatic speaker recognition systems identify humans by their voice.
Contact: Ulrike Glavitsch
Project funding: Gebert Rüf Stiftung
Duration: 2014 - 2016

Shockwave propagation in urban environments
On behalf of armasuisse a model is developed to numerically simulate and predict explosions and the subsequent nonlinear shockwave propagation in urban environments. The simulations will form a basis to determine safety distances.
Contact: Kurt Heutschi
Project funding: armasuisse
Duration: 2014 - 2016

Traffic Noise Auralisator: Within the research project TAURA, a traffic noise auralisator will be developed that covers road traffic and railway noise. The key element is a synthesizer that simulates the acoustical emission of a great many of different vehicles, operating on a wide variety of surfaces and under different operating conditions. To obtain the corresponding steering parameters, a hierarchic synthesizer structure with core parameters and global parameters is proposed. Together with the simulation of sound propagation phenomena and a multi-channel reproduction system, complex traffic noise scenarios can be artificially generated and ultimately listened at.
Contact: Reto Pieren
Project funding: SNF
Duration: 2014 - 2016

PhD Thesis  “Direct and Flanking Transmission in Combined Heavyweight and Lightweight Structures“
The aim of this work is to significantly extend calculation techniques for determining sound transmission in wooden structures. This will allow the accuracy of predictions to be significantly increased in comparison to the current, unsatisfactory methods.
PhD Student: Claire Churchill
Supervisor: Prof. Carl Hopkins, Acoustics Research Unit, University of Liverpool


Investigation of low frequency building acoustic measurements in small rooms
Contact: Stefan Schoenwald
Project funding: BAFU

Investigation of ground vibration caused by railway-turnout interactions
Contact: Armin Zemp
Project funding: SBB

Noise emission model for parked trains
Contact: Barbara Locher
Project funding: BAFU, SBB

Optimizing PC-21 Noise Emissions
Contact: Beat Schäffer
Project funding: armasuisse

VisAsim - Visual-Acoustics Simulation for landscape impact assessment of wind farms
Contact: Kurt Heutschi, Reto Pieren
Project partner: ETH Zürich, PLUS (Projektleitung)
Project funding: SNF


Acoustic Panel System
Each architecture constitutes acoustic resonances. Although this is an important factor in the perception of architectural spaces, it is not properly regarded in the planning process. Generally, this leads to belated “acoustic cosmetics”, which are applied on finished architectures.
This project therefore investigates the possibilities offered by the use of digital design tools and robot based fabrication methods to implement acoustical needs at an early stage into the designprocess of a flexible panelsystem which therefore can be individually adapted to different locations and their specific needs.
Contact: Kurt Eggenschwiler
Project partner: Gramazio & Kohler, Architektur und Digitale Fabrikation, ETH Zürich (Projektleitung), REHAU Vertriebs AG, Jürgen Strauss
Project funding: KTI

ASTRA-Projekt: Nächtliche Immissionsprognosen von Strassenlärm (Hochleistungsstrassen)
Contact: Kurt Heutschi
Project partner: B + S Ingenieur AG
Project funding: ASTRA

Sound-Absorbing, Transparent and Lightweight Acoustic Textiles
The team of Annette Douglas, Weisbrod-Zürrer AG und Empa have succeeded for the first time in developing translucent, lightweight curtains which are also sound absorbing. The drapes, which have been created as part of a CTI sponsored project, are excellent absorbers of noise and can be used in a wide range of applications. Until now only heavy, opaque curtains were capable of absorbing high levels of noise – light, translucent curtains usable for this purpose did not exist. Annette Douglas, a successful designer and winner of many awards, recognized this gap in the market and launched a CTI-supported project together with the innovative textile company Weisbrod-Zürrer AG and Empa (in both St. Gallen und Duebendorf). The aim was to develop translucent, light, non-flammable curtains which would satisfy very high design requirements whilst simultaneously offering good sound absorbing characteristics. The Acoustics / Noise Reduction Laboratory developed a mathematical model which mapped both the microscopic pattern of the textile as well as its macroscopic structure. With the help of a large number of acoustic measurements taken on woven samples purpose-made by Weisbrod-Zürrer, a requirement profile for the acoustic optimization of the textiles was determined. Annette Douglas succeeded in transforming these new results into actual textile samples, following which Weisbrod-Zürrer AG were able to optimize their production processes to allow the required properties to be integrated into textiles manufactured on an industrial scale. The range of sound absorbing materials available has now been extended to include a product which has long been on everyone's "wish list". The new, light, transparent sound absorbing curtains are now on the market and will, in future, help to provide significantly better acoustics in innumerable rooms.
Contact: Kurt Eggenschwiler, Reto Pieren
Project partner: Annette Douglas Textiles AG, Weisbrod-Zürrer
Project funding: KTI


A new method of measuring walking noise on floors
To date in order to evaluate walking noise on a laminated floor the sound of a lady walking on it was directly measured. The aim of the project was to develop a measurement technique which did not require the use of a human subject and also avoided the disadvantage of the ISO tapping machine. A suitable method has been developed and this is been validated by means of a survey. Finally a novel impacting device has been developed which operates very quietly.


Study on the effects of church bells on sleep quality (together with ETH Zurich):
Brink, M., S. Omlin, C. Müller, R. Pieren, and M. Basner, 2011. An event-related analysis of awakening reactions due to nocturnal church bell noise. Science of the Total Environment 409, 5210-5220.

Shooting noise study to establish a scientific basis for Annex 9 of the Noise Abatement Ordinance (together with ETH Zurich)
Brink, M. and J.M. Wunderli, 2010. A field study of the exposure-annoyance relationship of military shooting noise. Journal of the Acoustical Society of America 127, 2301-2311.

Development of the calculation model sonRAIL on behalf of the Swiss Federal Office for the Environment (FOEN)