We have a PhD student opening in our team. The topic of the research is room acoustics modeling and optimization, and it is funded by this 4-year Academy of Finland project. The application deadline is Sept. 23rd.

Nine awards ($500 each) were given to best student papers in International Symposium of Room Acoustics (ISRA 2013) conference, held in Toronto June 9-11 2013.  The decisions were based on the quality of submitted full papers and the committee said that the quality of all awarded papers were high. Two out of these nine awarded papers were from our Virtual Acoustics team, namely:

[1] A Haapaniemi, A Southern and T Lokki. A finite-difference time-domain investigation of reflections from layered wall structures. In International Symposium on Room Acoustics (ISRA 2013). 2013. URL BibTeX / Info

@inproceedings{haa13isra,
	address = "Toronto, Canada",
	author = "A. Haapaniemi and A. Southern and T. Lokki",
	booktitle = "International Symposium on Room Acoustics (ISRA 2013)",
	date-added = "2013-03-13 17:35:54 +0200",
	date-modified = "2013-03-13 17:35:54 +0200",
	keywords = "Wave-based models, Concert hall acoustics",
	month = "June 9-11",
	title = "A finite-difference time-domain investigation of reflections from layered wall structures",
	url = "https://mediatech.aalto.fi/~ktlokki/Publs/isra2013_P039.pdf",
	year = 2013,
	bdsk-url-1 = "https://mediatech.aalto.fi/~ktlokki/Publs/isra2013_P039.pdf"
}

[2] A Kuusinen and T Lokki. Individual differences in quality judgments and preferences of concert hall acoustics. In International Symposium on Room Acoustics (ISRA 2013). 2013. URL BibTeX / Info

@inproceedings{kuu13isra,
	address = "Toronto, Canada",
	author = "A. Kuusinen and T. Lokki",
	booktitle = "International Symposium on Room Acoustics (ISRA 2013)",
	date-added = "2013-03-13 17:35:54 +0200",
	date-modified = "2013-03-13 17:35:54 +0200",
	keywords = "Concert hall acoustics",
	month = "June 9-11",
	title = "Individual differences in quality judgments and preferences of concert hall acoustics",
	url = "https://mediatech.aalto.fi/~ktlokki/Publs/isra2013_P019.pdf",
	year = 2013,
	bdsk-url-1 = "https://mediatech.aalto.fi/~ktlokki/Publs/isra2013_P019.pdf"
}
 

Congrats to Antti and Aki!

The awards were funded by equal contributions from the Acoustical Society of America (ASA), the International Commission on Acoustics (ICA), and ARUP.
 

Professor Tapio Lokki of the Virtual Acoustics team will get one of the most presitigous awards in the field of acoustics, the ICA Early Career Award. The award ceremony will take place in the International Congress in Acoustics in Montreal, Canada on June 5th. Tapio will get the award for his outstanding contributions to room acoustics, particularly for novel subjective and objective assessment methods of concert halls. 

This research attempts to explain why some concert halls sound better than others and what perceptual attributes contribute to the general opinion of extraordinary acoustics.  Subjective comparison of concert halls is not an easy task, because preferred acoustics depend on a number of elements. The music, the conductor, and the performance of the orchestra greatly affect the listening experience, and the contribution of the auditorium acoustics are hard to isolate with subjective surveys.

To overcome these challenges, we have developed several new technologies and techniques. The first is a loudspeaker orchestra, which standardizes the musical performance. The second is spatial sound field analysis, which allows us to evaluate the effect of the auditorium. And finally, sensory evaluation methodology borrowed from the food and wine industry allows us to evaluate the multidimensional perceptual aspects of the experience. The combination of sensory profiles and spatial analyses have resulted in an interpretation of what physical characteristics of the sound field result in the perception of great acoustics.  With these methods we have made major advances in room acoustic evaluation. More information on this research can be found here.

See also press releases in Finnish and in English.

10 members of the Virtual Acoustics Group are visiting three conferences in Canada in May and June. In total, we  have 12 presentations. You can find us in Vancouver (ICASSP 2013, 26-31 May), Montreal (ICA 2013 2-7 June) , and Toronto (ISRA 2013 9-11 June). The presentations include our most recent findings in room acoustics modeling, concert hall acoustic measurements and analysis, subjective preference of concert halls, as well as many other related research topics.

 Here is the list of presentations/papers.

[1] J Botts and L Savioja. Integrating Finite Difference Schemes for Scalar and Vector Wave Equations. In IEEE Int. Conf. Acoust., Speech, Signal Processing. 2013. BibTeX / Info

@inproceedings{Botts_ICASSP_2013,
	address = "Vancouver, BC, Canada",
	author = "Botts, J. and Savioja, L.",
	booktitle = "IEEE Int. Conf. Acoust., Speech, Signal Processing",
	title = "Integrating Finite Difference Schemes for Scalar and Vector Wave Equations",
	year = 2013,
	abstract = "Room acoustic simulation is the process of generating approximate solutions to either the linearized Euler equations or the scalar wave equation. As for the continuous equations, the discrete approximations of both are equivalent. The vector formulation is less efficient, but it can inform several unexploited features of the scalar formulation. This paper first demonstrates the equivalence of the two schemes and explores how the vector formulation may be integrated into the more efficient scalar formulation to produce local velocity estimates and velocity sources on the pressure grid."
}

[2] S Siltanen, A Southern and L Savioja. Finite-Difference Time Domain Method Source Calibration for Hybrid Acoustics Modeling. In IEEE Int. Conf. Acoust., Speech, Signal Processing. 2013. BibTeX / Info

@inproceedings{Siltanen_ICASSP_2013,
	address = "Vancouver, BC, Canada",
	author = "Siltanen, S. and Southern, A. and Savioja, L.",
	booktitle = "IEEE Int. Conf. Acoust., Speech, Signal Processing",
	title = "Finite-Difference Time Domain Method Source Calibration for Hybrid Acoustics Modeling",
	year = 2013,
	abstract = "Finite-difference time domain methods are commonly used for acoustics modeling of enclosed geometries. For large spaces and high frequencies, the computational requirements become prohibitive in practical use. Thus, geometric acoustics algorithms are used in those cases. The results of these two classes of algorithm can be combined to model the full acoustic response. To allow direct mixing of the results, the source strengths should be calibrated. This paper derives calibration factors for various finite-difference time domain methods. It is shown that the modelled acoustics responses can then be easily combined to synthesise wide-band hybrid responses."
}

[3] T Lokki. Sensory evaluation of concert hall acoustics. In the 21st International Congress on Acoustics (ICA'2013). 2013. URL BibTeX / Info

@inproceedings{lok13ica,
	address = "Montreal, Canada",
	author = "T. Lokki",
	booktitle = "the 21st International Congress on Acoustics (ICA'2013)",
	date-added = "2012-12-07 13:41:10 +0200",
	date-modified = "2013-01-14 00:20:30 +0200",
	keywords = "Concert hall acoustics",
	month = "June 2-7",
	note = "Plenary lecture",
	title = "Sensory evaluation of concert hall acoustics",
	url = "http://dx.doi.org/10.1121/1.4800481",
	year = 2013,
	bdsk-url-1 = "http://dx.doi.org/10.1121/1.4800481"
}

[4] S Tervo, J Pätynen and T Lokki. Spatio-temporal energy measurements in renowned concert halls with a loudspeaker orchestra. In the 21st International Congress on Acoustics (ICA'2013). 2013. URL BibTeX / Info

@inproceedings{ter13ica,
	address = "Montreal, Canada",
	author = {S. Tervo and J. P{\"a}tynen and T. Lokki},
	booktitle = "the 21st International Congress on Acoustics (ICA'2013)",
	date-added = "2012-12-07 13:37:09 +0200",
	date-modified = "2013-01-14 00:20:43 +0200",
	keywords = "Room acoustic analysis",
	month = "June 2-7",
	note = "Invited paper",
	title = "Spatio-temporal energy measurements in renowned concert halls with a loudspeaker orchestra",
	url = "http://dx.doi.org/10.1121/1.4799424",
	year = 2013,
	bdsk-url-1 = "http://dx.doi.org/10.1121/1.4799424"
}

[5] S Siltanen and A Southern. A hybrid acoustic model for room impulse response synthesis. In the 21st International Congress on Acoustics (ICA’2013). 2013. BibTeX / Info

@inproceedings{Siltanen:ICA:2013,
	address = "Montreal, Canada",
	author = "Siltanen, S. and Southern, A.",
	booktitle = "the 21st International Congress on Acoustics (ICA’2013)",
	title = "A hybrid acoustic model for room impulse response synthesis",
	month = "June 2-7",
	year = 2013
}

[6] Jonathan Botts. Nested sampling in practice. In 21st International Congress on Acoustics. 2013. BibTeX / Info

@inproceedings{Botts2013a,
	author = "Jonathan Botts",
	title = "Nested sampling in practice",
	booktitle = "21st International Congress on Acoustics",
	year = 2013,
	address = "Montreal, Canada",
	month = "{June 2-7}",
	note = "Invited"
}

[7] A Haapaniemi, A Southern and T Lokki. A finite-difference time-domain investigation of reflections from layered wall structures. In International Symposium on Room Acoustics (ISRA 2013). 2013. URL BibTeX / Info

@inproceedings{haa13isra,
	address = "Toronto, Canada",
	author = "A. Haapaniemi and A. Southern and T. Lokki",
	booktitle = "International Symposium on Room Acoustics (ISRA 2013)",
	date-added = "2013-03-13 17:35:54 +0200",
	date-modified = "2013-03-13 17:35:54 +0200",
	keywords = "Wave-based models, Concert hall acoustics",
	month = "June 9-11",
	title = "A finite-difference time-domain investigation of reflections from layered wall structures",
	url = "https://mediatech.aalto.fi/~ktlokki/Publs/isra2013_P039.pdf",
	year = 2013,
	bdsk-url-1 = "https://mediatech.aalto.fi/~ktlokki/Publs/isra2013_P039.pdf"
}

[8] P W Robinson, S Siltanen, T Lokki and L Savioja. Concert hall geometry optimization with parametric modeling tools and wave-based acoustic simulations. In International Symposium on Room Acoustics (ISRA 2013). 2013. URL BibTeX / Info

@inproceedings{rob13isra,
	address = "Toronto, Canada",
	author = "P. W. Robinson and S. Siltanen and T. Lokki and L. Savioja",
	booktitle = "International Symposium on Room Acoustics (ISRA 2013)",
	date-added = "2013-03-13 17:35:54 +0200",
	date-modified = "2013-03-13 17:35:54 +0200",
	keywords = "Concert hall acoustics",
	month = "June 9-11",
	title = "Concert hall geometry optimization with parametric modeling tools and wave-based acoustic simulations",
	url = "https://mediatech.aalto.fi/~ktlokki/Publs/isra2013_P038.pdf",
	year = 2013,
	bdsk-url-1 = "https://mediatech.aalto.fi/~ktlokki/Publs/isra2013_P038.pdf"
}

[9] S Tervo, J Pätynen and T Lokki. Spatial analysis of concert hall impulse responses. In International Symposium on Room Acoustics (ISRA 2013). 2013. URL BibTeX / Info

@inproceedings{ter13isra,
	address = "Toronto, Canada",
	author = {S. Tervo and J. P{\"a}tynen and T. Lokki},
	booktitle = "International Symposium on Room Acoustics (ISRA 2013)",
	date-added = "2013-03-13 17:35:54 +0200",
	date-modified = "2013-03-13 17:35:54 +0200",
	keywords = "Room acoustic analysis",
	month = "June 9-11",
	title = "Spatial analysis of concert hall impulse responses",
	url = "https://mediatech.aalto.fi/~ktlokki/Publs/isra2013_P049.pdf",
	year = 2013,
	bdsk-url-1 = "https://mediatech.aalto.fi/~ktlokki/Publs/isra2013_P049.pdf"
}

[10] J Pätynen, S Tervo and T Lokki. Binaural dynamic responsiveness in concert halls. In International Symposium on Room Acoustics (ISRA 2013). 2013. URL BibTeX / Info

@inproceedings{pat13isra,
	address = "Toronto, Canada",
	author = {J. P{\"a}tynen and S. Tervo and T. Lokki},
	booktitle = "International Symposium on Room Acoustics (ISRA 2013)",
	date-added = "2013-03-13 17:35:54 +0200",
	date-modified = "2013-03-13 17:35:54 +0200",
	keywords = "Concert hall acoustics, Room acoustic analysis",
	month = "June 9-11",
	title = "Binaural dynamic responsiveness in concert halls",
	url = "https://mediatech.aalto.fi/~ktlokki/Publs/isra2013_P046.pdf",
	year = 2013,
	bdsk-url-1 = "https://mediatech.aalto.fi/~ktlokki/Publs/isra2013_P046.pdf"
}

[11] A Kuusinen and T Lokki. Individual differences in quality judgments and preferences of concert hall acoustics. In International Symposium on Room Acoustics (ISRA 2013). 2013. URL BibTeX / Info

@inproceedings{kuu13isra,
	address = "Toronto, Canada",
	author = "A. Kuusinen and T. Lokki",
	booktitle = "International Symposium on Room Acoustics (ISRA 2013)",
	date-added = "2013-03-13 17:35:54 +0200",
	date-modified = "2013-03-13 17:35:54 +0200",
	keywords = "Concert hall acoustics",
	month = "June 9-11",
	title = "Individual differences in quality judgments and preferences of concert hall acoustics",
	url = "https://mediatech.aalto.fi/~ktlokki/Publs/isra2013_P019.pdf",
	year = 2013,
	bdsk-url-1 = "https://mediatech.aalto.fi/~ktlokki/Publs/isra2013_P019.pdf"
}

[12] T Lokki. Throw away that standard and listen: your two ears work better. In International Symposium on Room Acoustics (ISRA 2013). 2013. URL BibTeX / Info

@inproceedings{lok13isra,
	address = "Toronto, Canada",
	author = "T. Lokki",
	booktitle = "International Symposium on Room Acoustics (ISRA 2013)",
	date-added = "2013-03-13 17:35:54 +0200",
	date-modified = "2013-03-13 17:35:54 +0200",
	keywords = "Concert hall acoustics, Room acoustic analysis",
	month = "June 9-11",
	title = "Throw away that standard and listen: your two ears work better",
	url = "https://mediatech.aalto.fi/~ktlokki/Publs/isra2013_P040.pdf",
	year = 2013,
	bdsk-url-1 = "https://mediatech.aalto.fi/~ktlokki/Publs/isra2013_P040.pdf"
}
 

The researchers of the Virtual Acoustics Research group, Dr. Sakari Tervo, Dr. Jukka Pätynen, and PhD Philip Robinson, M.Sc. Antti Kuusinen, and M.Sc. Aki Haapaniemi, received the Matti Karjalainen-Trust Award for their research work on concert hall acoustics. The Matti Karjalainen-trust committee considered that the researchers have done an exceptional work on the development of the measurement and analysis tools for concert hall acoustics. The award was given to the researchers in 22nd of May 2013 in Turku in Akustiikkapäivät 2013, a Finnish Acoustical Society Meeting.  

Introduction

This spring, members of the Virtual Acoustics Team conducted a Media Technology Seminar: Applied Data Analysis and Visualization. The concept of the course was to explore new methods to visualize spatial acoustic room impulse responses. Students from the media technology and computer science departments, some without prior acoustics knowledge, brought diverse skills and expertise to the seminar and produced a variety of animated and interactive graphics to illustrate the high-dimensional data.  

The data set is a collection of acoustic room impulse responses that the Virtual Acoustics Team measured during a tour of 10 of Europe's great concert halls, in November of 2012. Measurements were conducted with 36 loudspeakers on the stage of each hall, and for multiple listening positions in the audience areas. The receiver was a 6 microphone array, which allowed post-processing to determine the direction of arrival of the sound at each instant in the impulse response.  This processing was conducted prior to handing the data over to the students. Thus, the data were multi-dimensional, at least 8 dimensions could be represented. Students were encouraged to explore visualizing source positions, receiver positions, three-dimensional spatial aspects, temporal development, frequency characteristics, and comparisons between halls.  

 While students were expected to have basic knowledge of computer graphics, their backgrounds were diverse. Some were members of the Virtual Acoustics Team and were well versed in room acoustics techniques, while others had no previous experience with acoustics, but brought programming, computer graphics, or other expertise to the group. For this reason, students were paired in an attempt to maximize synergies. Specific methods or software were not dictated in order to prevent limiting the possible outcomes. 

The first task for each student was to produce a 3D model of one of the concert halls. This exercise allowed the students to become familiar with the spaces the measured data were taken from, and the models provided a context for the data visualizations.  The students were encouraged to incorporate the visualizations into the models to provide an environmental context for the data, and this was accomplished with various degrees of success.

The second task was to create an animation or interactive graphic to represent the data.  The students produced several novel visualizations, which are displayed here.

Lateral plane energy distribution in octave bands. Aki Haapaniemi and Petri Leskinen

This visualization demonstrates the lateral energy, integrated over a given time window, and divided into octave bands. It is novel because, while time-frequency plots and, spatial energy plots have been utilized in the past, spatial frequency plots are much less common in room acoustics. The data disk is located within the hall at the receiver position, and the energy from each direction is highlighted in green. Octave bands are illustrated in concentric circles, with the lowest frequencies at the center. Interactive sliders allow the viewer to examine various time windows.

 

Nested tesselated spheres. Petri Leskinen and Aki Haapaniemi

Similar to the previous one, this visualization places a representation of the sound energy within the concert hall model, at the receiver location. Here, the data are represented in broadband, rather than in octave bands, but several time windows can be nested to examine the early and late sound responses simultaneously. The graphic is interactive to allow the viewer to fly around and zoom the response.

Dynamic sound arrivals. Morley Zan-Bi and Antti Kuusinen

This visualization is based on the open-source package Processing. The concept is to visualize the time and direction of arriving sound with parallelepipeds that converge on the listening position. In this image the sound source is to the right and the listener position is at the center. The direct sound is indicated in red, the early reflections in green, and the late reverberation in blue.  The size of each particle and its final distance from the receiver position represent the strength of the reflection at that particular time instant. The visualization is animated to allow the viewer to watch the development of the room response over time, and interactive to allow the user to pan and zoom around the response for a complete view.

Spherical Energy. Hannu Järvinen and Timo Rutanen

The final visualization takes a similar approach and animates the sound arrival strengths and directions. Frames include approximately 1 ms of data and are overlapped 50%. The particles are positioned at a distance from the receiver proportional to their strength and in the direction of their arrival.

 

 

Conclusion

 

A design studio approach to the data visualization course allowed the students to use their own creativity to illustrate a large database of high dimensional data.  The measured concert hall data provided and interesting and challenging context for this exploration. The resulting novel visualization techniques may have further utility for room acoustics research and are a tangible and useful course outcome. 

 

Virtual Acoustics Team is conducting a workshop Capturing the Acoustics of Concert Halls with a Loudspeaker Orchestra on Saturday, May 4, 10:30 — 12:30 in AES 134, Rome, in Auditorium Loyola

The workshop will include presentations from Prof. Lokki, and Drs. Pätynen and Tervo, on the subjective and objective evaluation of concert halls.

In the last 5 years, Virtual acoustics team has measured 20 concert halls with a loudspeaker orchestra, which consists of 34 loudspeakers. In the measurements, spatial room impulse responses are measured from the loudspeakers to a microphone array. These impulse responses are further processed for analysis and synthesis purposes. The presentations will include a detailed description of these techniques and practicalities related to the measurements.

 

The Virtual Acoustics team has recently worked hard to finalize six papers that will be presented next June in International Symposium on Room Acoustics (ISRA 2013). We are really looking forward to a great conference in Toronto, Canada.

Two of the papers deal with room acoustics modeling. Haapaniemi et al. [1] discuss about reflection of sound from layered structures often used in concert halls. The results show how sound is attenuated at some frequencies and how well such structures diffuse sound. Robinson et al. [2] introduce a project in which best shapes of side walls and side balconies are searched with automatic optimization of geometry. 

Tervo et al. [3] extend a recently published Spatial Decomposition Method to perform the analysis on frequency bands. The paper also shows visualizations on sound energy distribution in two concert halls. Pätynen et al. [4] show that when an orchestra plays in fortissimo the spectrum of sound is quite different than in pianissimo. Thus, the music has non-linear characteristics that are earlier neglected in room acoustics studies. Moreover, human (spatial) hearing is also highly non-linear, another aspect that should be considered seriously in concert hall acoustics studies.

Kuusinen et al. [5] analyse the behavior of individual assessors in our recent studies (IVP1 in 2011 and IVP2 in 2012) on concert hall acoustics with individual vocabulary profiling technique. The analysis reveals that subjects behave quite differently when they are creating individual discriminating attributes for comparison of concert halls. Finally, Lokki gathers, in his keynote paper [6], the current knowledge of the team by presenting some interesting time-frequency and spatiotemporal analysis of famous European concert halls that we have recently measured.

 

[1] A Haapaniemi, A Southern and T Lokki. A finite-difference time-domain investigation of reflections from layered wall structures. In International Symposium on Room Acoustics (ISRA 2013). 2013. BibTeX / Info

@inproceedings{haa13isra,
	address = "Toronto, Canada",
	author = "A. Haapaniemi and A. Southern and T. Lokki",
	booktitle = "International Symposium on Room Acoustics (ISRA 2013)",
	date-added = "2013-03-13 17:35:54 +0200",
	date-modified = "2013-03-13 17:35:54 +0200",
	keywords = "Wave-based models, Concert hall acoustics",
	month = "June 9-11",
	title = "A finite-difference time-domain investigation of reflections from layered wall structures",
	year = 2013
}

[2] P W Robinson, S Siltanen, T Lokki and L Savioja. Concert hall geometry optimization with parametric modeling tools and wave-based acoustic simulations. In International Symposium on Room Acoustics (ISRA 2013). 2013. BibTeX / Info

@inproceedings{rob13isra,
	address = "Toronto, Canada",
	author = "P. W. Robinson and S. Siltanen and T. Lokki and L. Savioja",
	booktitle = "International Symposium on Room Acoustics (ISRA 2013)",
	date-added = "2013-03-13 17:35:54 +0200",
	date-modified = "2013-03-13 17:35:54 +0200",
	keywords = "Concert hall acoustics",
	month = "June 9-11",
	title = "Concert hall geometry optimization with parametric modeling tools and wave-based acoustic simulations",
	year = 2013
}

[3] S Tervo, J Pätynen and T Lokki. Spatial analysis of concert hall impulse responses. In International Symposium on Room Acoustics (ISRA 2013). 2013. BibTeX / Info

@inproceedings{ter13isra,
	address = "Toronto, Canada",
	author = {S. Tervo and J. P{\"a}tynen and T. Lokki},
	booktitle = "International Symposium on Room Acoustics (ISRA 2013)",
	date-added = "2013-03-13 17:35:54 +0200",
	date-modified = "2013-03-13 17:35:54 +0200",
	keywords = "Room acoustic analysis",
	month = "June 9-11",
	title = "Spatial analysis of concert hall impulse responses",
	year = 2013
}

[4] J Pätynen, S Tervo and T Lokki. Binaural dynamic responsiveness in concert halls. In International Symposium on Room Acoustics (ISRA 2013). 2013. BibTeX / Info

@inproceedings{pat13isra,
	address = "Toronto, Canada",
	author = {J. P{\"a}tynen and S. Tervo and T. Lokki},
	booktitle = "International Symposium on Room Acoustics (ISRA 2013)",
	date-added = "2013-03-13 17:35:54 +0200",
	date-modified = "2013-03-13 17:35:54 +0200",
	keywords = "Concert hall acoustics, Room acoustic analysis",
	month = "June 9-11",
	title = "Binaural dynamic responsiveness in concert halls",
	year = 2013
}

[5] A Kuusinen and T Lokki. Individual differences in quality judgments and preferences of concert hall acoustics. In International Symposium on Room Acoustics (ISRA 2013). 2013. BibTeX / Info

@inproceedings{kuu13isra,
	address = "Toronto, Canada",
	author = "A. Kuusinen and T. Lokki",
	booktitle = "International Symposium on Room Acoustics (ISRA 2013)",
	date-added = "2013-03-13 17:35:54 +0200",
	date-modified = "2013-03-13 17:35:54 +0200",
	keywords = "Concert hall acoustics",
	month = "June 9-11",
	title = "Individual differences in quality judgments and preferences of concert hall acoustics",
	year = 2013
}

[6] T Lokki. Throw away that standard and listen: your two ears work better. In International Symposium on Room Acoustics (ISRA 2013). 2013. BibTeX / Info

@inproceedings{lok13isra,
	address = "Toronto, Canada",
	author = "T. Lokki",
	booktitle = "International Symposium on Room Acoustics (ISRA 2013)",
	date-added = "2013-03-13 17:35:54 +0200",
	date-modified = "2013-03-13 17:35:54 +0200",
	keywords = "Concert hall acoustics, Room acoustic analysis",
	month = "June 9-11",
	title = "Throw away that standard and listen: your two ears work better",
	year = 2013
}
 

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