Saturday, May 20, 09:30 — 12:30 (Gallery Window)
P03-01 Analysis of the Subgrouping Practices of Professional Mix Engineers
David Michael Ronan (Presenting Author), Hatice Gunes (Author), Joshua D. Reiss (Author)
Subgrouping facilitates the simultaneous manipulation of a number of audio tracks and is a central aspect of mix engineering. However, the decision process of subgrouping is a poorly documented technique. This study sheds light on this ubiquitous but poorly defined mix practice and provides rules and constraints derived from a questionnaire that could be used in intelligent audio production tools. We prepared an online questionnaire consisting of 21 questions testing nine assumptions and identifying subgrouping decisions, such as why a mix engineer creates subgroups, when they subgroup and how many subgroups they use. We analyzed responses from 10 award winning mix engineers. Thematic analysis enabled us to discover five themes: Decisions, Subgroup Effect Processing, Organization, Exercising Control, and Analogue versus Digital. By analyzing the themes and each respondent’s quantitative data we were able to show that eight out of nine assumptions could be accepted to be true.
Convention Paper 9700
P03-02 Combining Preference Ratings with Sensory Profiling for the Comparison of Audio Reproduction Systems
Tim Walton (Presenting Author), Michael Evans (Author), David Kirk (Author), Frank Melchior (Author)
One aim of perceptual audio evaluation is to understand the relationships between individual sensory attributes and overall quality of experience. This paper discusses one perceptual evaluation method by which this can be realized. Open Profiling of Quality (OPQ), a method first introduced in the field of visual and audiovisual evaluation, involves psychoperceptual evaluation, sensory profiling, and external preference mapping stages and is suitable for use with naïve listeners. Here, a methodological case study is presented in which we discuss the implementation of this method and its adaptation for the comparison of audio reproduction systems.
Convention Paper 9701
P03-03 The Audience Effect on the Acoustics of Ancient Theaters in Modern Use
Gino Iannace (Presenting Author), Amelia Trematerra (Author)
Ancient theaters are used in modern contexts for different types of shows. When ancient theaters are used for musical performances, the audience criticizes the acoustics due to either not being able to understand what is spoken or the weakness of the music. An important aspect is the presence of the audience in the cavea, with it being important to understand whether it can have a negative role. Since it is not possible to take acoustic measurements during theater performances, the evaluation of the effects of the presence of the audience on the acoustics is carried out virtually through the software, “Odeon,” in which the presence of the audience is simulated by changing the absorption coefficient value of the cavea.
Convention Paper 9702
P03-04 Evaluation of Training to Improve Auditory Memory Capabilities on a Mobile Device Based on a Serious Game Application
György Wersényi (Presenting Author), Hunor Nagy (Author)
Capabilities of the auditory memory system were tested in a serious game application developed for the Android mobile platform. Participants played the well-known game of finding pairs by flipping and remembering objects on cards arranged in a matrix structure. Visual objects were replaced by iconic auditory events (auditory icons, earcons). Total time and different error rates were recorded and the effect of training was also evaluated. Results indicate that training contributes to a better performance and human voice samples are the easiest to remember.
Convention Paper 9703
P03-05 Conversational Speech Quality in Noisy Environments
Michal Soloducha (Presenting Author), Stefan Bleiholder (Author), Frank Kettler (Author), Alexander Raake (Author)
The present study reports on a conversation test conducted to reveal insights on how telephony users perceive speech transmission quality in a noisy environment. For this purpose, a telephony setup has been built to simulate different degradations typical of real-life situations. A range of different conditions has been presented during the subjective test including usage of different terminals, environmental noises, and a noise suppression algorithm. A noise reproduction system has been installed on one side of the telecommunication channel to create an immersive noisy environment. Special focus of this paper is on the influence of different terminal devices and their signal processing on subjective quality. Moreover, more generic conclusions regarding conversational quality testing are provided.
Convention Paper 9704
P03-06 Acoustic Room Modelling Using a Spherical Camera for Reverberant Spatial Audio Objects
Luca Remaggi (Presenting Author), Trevor J. Cox (Author), Adrian Hilton (Author), Richard J. Hughes (Author), Philip J. B. Jackson (Author), Hansung Kim (Author), Ben Shirley (Author)
The ability to predict the acoustics of a room without acoustical measurements is a useful capability. The motivation here stems from spatial audio reproduction, where knowledge of the acoustics of a space could allow for more accurate reproduction of a captured environment, or for reproduction room compensation techniques to be applied. A cuboid-based room geometry estimation method using a spherical camera is proposed, assuming a room and objects inside can be represented as cuboids aligned to the main axes of the coordinate system. The estimated geometry is used to produce frequency-dependent acoustic predictions based on geometrical room modelling techniques. Results are compared to measurements through calculated reverberant spatial audio object parameters used for reverberation reproduction customized to the given loudspeaker set up.
Convention Paper 9705
P03-07 Estimating the Diffuseness Level of the Acoustic Field—Reverberation Chamber Under Study
Bartlomiej Chojnacki (Presenting Author), Artur Flach (Author), Tadeusz Kamisinski (Author), Adam Pilch (Author)
A reverberation chamber is a widely used type of a laboratory room for widespread usage of standards like a ISO 354, ISO 17497-1 or ISO 3741. Chambers' shapes and types vary a lot around the world and so do the results of the sound absorption coefficient measurements, even though they meet the standard criteria. Verification of the ISO standards parameters is required, also introducing extra parameters describing the level of sound field diffuseness. Model studies have been conducted using the ray-tracing method in order to verify the level of sound field diffuseness in varying versions of irregular reverberation chamber, further rated with kurtosis of room normalized impulse response and sound field diffuseness coefficient, in order to assess the geometries under study.
Convention Paper 9706
P03-08 Environmental and Technical Problems in Acoustical Scaled Models
Aleksandra Majchrzak (Presenting Author), Katarzyna Baruch (Author), Bartlomiej Chojnacki (Author), Jaroslaw Rubacha (Author)
Using acoustical scaled models provides numerous theoretical and practical issues. After formulating theoretical requirements regarding the sound field in a given object, one should also conduct considerable amount of measurements of acoustical properties of materials to be used in a construction or the sound source. The paper discusses difficulties met during performing acoustical measurements in a scaled reverberation chamber in Technical Acoustics Laboratory AGH, such as utilized sound sources and the ways of adjusting atmospheric conditions (relative humidity and temperature). The paper particularly concerns the ideas of changing the conditions of measurement environment, sound sources being in use and the frequency range of the performed measurements.
Convention Paper 9707
P03-09 OpenAirLib: A JavaScript Library for the Acoustics of Spaces
Damian Murphy (Presenting Author), Kenneth Brown (Author), Matthew Paradis (Author)
The possibilities for creating online sonic art and virtual acoustic environments have been increased by the introduction of audio Application Programming Interfaces, libraries, and online resources of acoustic impulse responses (which encapsulate the acoustics of real or imaginary spaces.) This paper presents the OpenAirLib JavaScript library that extends the capabilities of the World Wide Web Consortium Web Audio API, facilitating the incorporation of three-dimensional acoustics of spaces into web audio projects. It enables first-order ambisonic material from the Open Acoustic Impulse Response Library (OpenAIR) website to superimpose the acoustics of one space onto synthesized or recorded material from another space. An example is then described which uses these technologies to produce instances of generative online sonic art from OpenAIR data.
Convention Paper 9708
P03-10 Measurement and Visualization of Sound Intensity Vector Distribution in Proximity of Acoustic Diffusers
Adam Kurowski (Presenting Author), Bozena Kostek (Author), József Kotus (Author)
In this work, we would like to present analyses and visualizations of sound intensity distribution measured in proximity of an acoustic diffuser. Such distribution may be used for estimation of basic acoustic parameters of a diffuser. Measurement is performed with the use of a logarithmic sine sweep that allows for the analysis of waves scattered by the diffuser and rejecting the direct sound signal component. Pressure and sound intensity vector impulse responses are measured simultaneously. The measurement is carried out for a grid of 37 points arranged at equal intervals lying in a semicircle. To investigate the impact of objects evaluated on the sound wave propagation diffusion coefficients and sound intensity vector distributions are then compared.
Convention Paper 9709