Signal Processing and Speech Communication Laboratory
hometheses & projects › Measuring Reverberation Time In Acoustic MIMO Systems

Measuring Reverberation Time In Acoustic MIMO Systems

In work
Master Project
Announcement date
03 Feb 2021
Clemens Frischmann
Research Areas


In room acoustics a versatile approach becomes more and more mandatory due to the variety of events in one venue. Adjustable acoustic conditions can be accomplished with traditional methods by, for instance, adjustable absorbers and coupled rooms, or in a more modern approach by active acoustics or acoustic enhancement systems. To implement, calibrate and maintain such active systems, room acoustic and electroacoustic measurements have to be conducted. Therefore engineers and measurement equipment have to be brought in, to carry out these essential measurements. This is both time- and cost-intensive. So why not use the existing infrastructure of such systems and conduct measurements with the existing hardware? The aim of this work is to implement a measurement tool into an existing acoustic enhancement system (Amadeus Active Acoustics) to verify both the condition of elektroacoustic equipment and reverberation time. Therefore it has to be verified, if measurements conducted within the sytems infrastructure are at all usefull. The first part of the thesis to this abstract will consist of a comparison between measurements carried out with the systems infrastructure and the standardized measurement procedure (ISO 3382-1). Because no measurements have been conducted yet, this part will not be discussed in detail here. The second part is concerned with the implementation of the measurement algorithm. For an averagely sized system, consisting of about 60 loudspeakers and 30 microphones, the number of measurements and so the measurement time can grow enormously. Therefore it is key to minimize time consuption. This can be done by measuring less loudspeakers, if the results allow so. In this document two main approaches are discussed, multiple exponential sweep method (MESM) and an adaptive filter approach. There are drawbacks and advantages in both approaches. It should be evaluated which approach suits the existing system.