AES Budapest 2012
Paper Session P4
P4 - Sound Reinforcement and Studio Technologies
Thursday, April 26, 11:00 — 12:30 (Room: Liszt)
Chair:
Diemer de Vries
P4-1 Full Room Equalization at Low Frequencies with Asymmetric Loudspeaker Arrangements—Balázs Bank, Budapest University of Technology and Economics - Budapest, Hungary
For rectangular rooms with symmetric loudspeaker arrangements, full room equalization can be achieved at low frequencies, as demonstrated by previous research. The method is based on generating a plane wave that propagates along the room. However, often the room is not rectangular, and/or a symmetric loudspeaker setup cannot be assured, leading to a deteriorated equalization performance. In addition, the performance of the method drops significantly above a cutoff frequency where a plane wave cannot be generated. These problems are addressed by the proposed method by prescribing only the magnitude in the control points, while the phase is determined by an iterative optimization process starting from the plane wave solution. A true “magnitude-only” variant of the method is also presented. Comparison is given to the plane-wave based methods by introducing asymmetries to the loudspeaker setup in a simulated environment, showing that the new methods result in smaller average magnitude deviations compared to the previous plane-wave based approach.
Convention Paper 8593 (Purchase now)
P4-2 Linear Mixing Models for Active Listening of Music Productions in Realistic Studio Conditions—Nicolas Sturmel, Université Paris Diderot - Paris, France; Antoine Liutkus, Telecom ParisTech - Paris, France; Jonathan Pinel, Laurent Girin, GIPSA-Lab, Grenoble INP - Grenoble, France; Sylvain Marchand, Université de Bretagne Occidentale - Brest, France; Gaël Richard, Roland Badeau, Telecom ParisTech - Paris, France; Laurent Daudet, Université Paris Diderot - Paris, France
The mixing/demixing of audio signals as addressed in the signal processing literature (the “source separation” problem) and the music production in studio remain quite separated worlds. Scientific audio scene analysis rather focuses on “natural” mixtures and most often uses linear (convolutive) models of point sources placed in the same acoustic space. In contrast, the sound engineer can mix musical signals of very different nature and belonging to different acoustic spaces, and exploits many audio effects including nonlinear processes. In the present paper we discuss these differences within the strongly emerging framework of active music listening, which is precisely at the crossroads of these two worlds: it consists in giving to the listener the ability to manipulate the different musical sources while listening to a musical piece. We propose a model that allows the description of a general studio mixing process as a linear stationary process of “generalized source image signals” considered as individual tracks. Such a model can be used to allow the recovery of the isolated tracks while preserving the professional sound quality of the mixture. A simple addition of these recovered tracks enables the end-user to recover the full-quality stereo mix, while these tracks can also be used for, e.g., basic remix / karaoke / soloing and re-orchestration applications.
Convention Paper 8594 (Purchase now)
P4-3 Capturing Height: The Addition of Z Microphones to Stereo and Surround Microphone Arrays—Paul Geluso, New York University - New York, NY, USA
As surround systems with height channels become more commonplace, new microphone techniques to capture sound in 3-D are needed. In order for the height channels to be effective, they must contain sonic information that is compatible with the 5.1 surround channels in order to improve the listener’s sense of three-dimensional sound imaging, space, and immersion. Complex height information can be captured by pairing horizontally oriented microphones with vertically oriented bi-directional microphones. In this paper the author presents a rationale, methodology, and preliminary evaluation of a microphone technique based on this concept.
Convention Paper 8595 (Purchase now)
