International Symposium On Musical and Room Acoustics 

Pavel Zahorik

Using psychoacoustic approaches to understand and predict perception of sound in rooms

Room acoustics critically shape our perceptual listening experience. They can make or break musical performances or be the difference between successful and unsuccessful speech communication. Scientific study of room acoustics has identified a variety of metrics that describe various physical acoustic properties of rooms (e.g., ISO 3382), and many of these metrics have subsequently been shown to be associated with specific perceptual aspects of sound in rooms. Because the associations are complex and multidimensional, it is often difficult to conclusively link physical room-acoustic metrics to perception, however. Over the past half century, the field of psychoacoustics has developed and validated computational modeling techniques that describe and predict the function of the human auditory system at various mechanistic levels. The purpose of this talk is to suggest and to show that incorporating psychoacoustic modeling techniques into the associative process between physical room acoustics and perception can be hugely beneficial. A primary advantage of this approach is that it inserts a level of automaticity into the associative process that allows for many more associations to be explored and predicted. Additional advantages include the ability to flexibly examine effects of different source materials, dynamics, and listener characteristics, including the effects of hearing impairment and listening with hearing devices.

Pavel Zahorik is a Professor in the School of Communication Sciences and Disorders at the University of Central Florida, where he is proud to be part of a dynamic and growing research team at the Communication Technologies Research Center. From 2003 to 2023, Pavel was a faculty member at the University of Louisville, where he held the Heuser Hearing Research Professorship since 2013. He has studied human perception and performance in sound-reflective environments for over 25 years and has been funded by the NIH, the Air Force Office of Scientific Research, and Sonova. He is a Fellow of the Acoustical Society of America (ASA) and is currently the Associate Editor for the Journal of the Acoustical Society of America – Psychological Acoustics Technical Area.

Trimpin

Engaging the room: Contraptions for Art and Sound

Trimpin is an internationally renowned artist and composer whose work integrates sculpture and sound across a variety of media including fixed installation, live music, theater, and dance performance. His ingenious sound art installations, which typically feature the acoustics of everyday objects with computer controlled actuators, have been commissioned throughout Europe and North America. Based in the Pacific Northwest, Trimpin is a regular artist in residence at the California Institute of the Arts, Stanford’s CCRMA, and the MIT Center for Arts, Science, and Technology. He has collaborated with the playwright Samuel Becket, composer Conlan Nancarrow, and the Kronos Quartet, among others. He is a MacArthur Fellow and the subject of the 2011 Peter Esmonde documentary “Trimpin: the Sound of Invention”.

Margriet Lautenbach

Room acoustics for classical halls: Practice, theory and music

Room acoustics as a science is relatively young. When the Concertgebouw in Amsterdam was designed in the 1880’s, it wasn’t possible to hire an acoustician to join the design team. Knowledge about room acoustics started only a decade or so later, with the investigations of the well known W.C. Sabine.

More than a century later it still feels that there is a lot to gain in the knowledge of room acoustics, especially for non-amplified music. In a hall for classical music, room acoustics is the main tool to transfer the music form the musicians on stage to the listeners in the hall in the most beautiful way possible.

In this talk I want to reflect on different room acoustic aspects from the consultant (practical) point of view, being the bridge between musical goals and acoustical science. The design of a hall starts and ends with music. A client will emphasize his or her musical goals like sound quality, playing conditions on stage, surround sound and intimacy, presence and definition. In the design process the acoustic consultant has to mould these goals into numbers, parameters and models in order to transfer the musical goals into architectural requirements and solutions. With reference to the design process of recently finished concert halls like Kulturpalast Dresden and Casals Forum Kronberg we will compare these musical goals with the available acoustical knowledge from standards and literature, recent investigations and possible ways to think about acoustics and reflection patterns where proven knowledge still fails us.

Margriet Lautenbach is a room acoustic consultant for over 20 years. She has been investigating the use of calculation and scale models research as design tools. She was lead acoustician, or collaborated, in the design for the renovation of several theatres, opera halls and concert halls, such as Royal Theatre Carré Amsterdam, De Doelen concert hall Rotterdam, the Concertgebouw Amsterdam, the state opera in Berlin and the opera in Cologne. The experience from renovation projects with their possibility to compare models with the existing halls through measurements was of great advantage for the design of new concert halls as The Kulturpalast in Dresden, Parkzaal Musis in Arnhem and Casals Forum in Kronberg (Frankfurt).

Margriet has worked at Peutz from 2003 until 2022. In 2024 Margriet founded her own company Acoustic Reflections, as part of a not for profit organization with the mission: “More trees, more silence and more music”. Since 2019 Margriet is president of the Netherlands Acoustical Society and she teaches
room acoustics at the Higher Course in Acoustics in Antwerp.

Anders Friberg

Swing timing in a jazz ensemble: measurements and models

The groove or the swing is an important and unique aspect of classic jazz, debated and discussed among musicians and listeners based on the aural perception of the music. In the last decades there has been several objective timing studies showing that timing in a jazz ensemble follows an intricate pattern. The most well-known timing characteristic is the long-short pattern of consecutive eighth notes. However, it is varying for the instruments and is dependent on tempo. The instruments are also interlocked in a specific way, implying lack of synchronization on the downbeat. The soloist is typically playing behind the other instruments on the downbeat leading to what has been referred to as a “laid-back” playing. Intriguingly, some details of this interaction are often not even known to the jazz musicians themselves.

In this presentation I will give an overview of jazz timing measurements as well as presenting our recent models for controlling the timing in a jazz ensemble. The latter will be centered around four ensemble recordings of swing selected for their specific style led by Buddy Rich, Wynton Marsalis, Keith Jarrett and Peter Erskine. The role of these timing patterns as a tool for expression and possible usage of the models will be discussed.

These intricate timing patterns has presumably been developed in small jazz clubs in which the musicians are placed near each other and near the audience. Notably, jazz is still primarily performed in this way, thus enabling the utilization of micro-timing variations that can be perceived both by the musicians and the audience. Certainly, jazz concerts can also be appreciated in larger rooms with more reverberation but how this is perceived by the audience appears to be an open question.

Anders Friberg is Professor in music communication at KTH Royal Institute of Technology, Stockholm. He has been working mainly with the synthesis and analysis of music performance, leading to the rule system Director Musices translating the score to a performance. He has also been focusing on automatic extraction of music parameters from audio and its relation to emotional/motional expression. Recent works includes models for jazz timing, a model for dynamics in piano playing, and a model of immanent accents in music. On his free time, he is playing piano in several jazz groups.

Stefan Weinzierl

Generative design as a solution for room acoustic problems

In generative acoustic design, numerical methods are not used to test the acoustic behavior of a given scene, but rather to identify an acoustic scene that optimally produces a sound field with certain predefined characteristics. While this is a well-established practice in other disciplines such as architecture or structural design, it is only recently that several approaches have been explored in the field of room acoustics. These include (a) combining a generator with forward simulation and iterative optimization, (b) implementing differentiable geometric acoustic simulation and backpropagation from a target design, and (c) optimizing a wave-theoretic numerical solution to infer the geometry and boundary conditions that optimally generate a desired sound field. The talk will give examples of each of these approaches, discuss the challenges, and highlight the future potential for room acoustic design.

Stefan Weinzierl is head of the Audio Communication Group at the Technische Universität Berlin. His research focuses on audio technology, virtual acoustic reality, room acoustics, and musical acoustics. He coordinates a master’s program in Audio Communication and Technology at TU Berlin. With a diploma in physics and sound engineering, he received his Ph.D. in musical acoustics from TU Berlin. He has coordinated international research consortia in the fields of virtual acoustic reality (SEACEN) and music information retrieval (ABC_DJ), and is a valued consultant for room acoustics in the construction and renovation of theaters and concert halls.