1. Chair of Vibroacoustics of Vehicles and Machines, Boltzmannstrasse 15, Technical University of Munich, Garching, Bavaria 85748, Germany
2. SBS Bühnentechnik GmbH, Bosewitzer Strasse 20, Dresden, Saxony 01259, Germany
3. CADFEM-CIS, Kondrat'yevskiy Prospekt 15, Saint Petersburg, Northwestern Federal District 195197, Russia
4. Applied Mechanics Group, University of Applied Sciences, Kornmarkt 1, Zwickau, Saxony 08056, Germany
5. Centre for Audio, Acoustics and Vibration University of Technology Sydney, 15 Broadway, Sydney, New South Wales 2007, Australia
6. School of Engineering and Information Technology, University of New South Wales, Northcott Drive, Canberra, Australian Capital Territory 2612, Australia