Last Updated: 20050916, saj
Monday, October 10, 10:00 am — 12:00 pm
Chair: Gilbert Soulodre, Communications Research Centre - Ottowa, Ontario, Canada
P17-1 Stereo and Multichannel Loudness Perception and Metering—Gilbert Soulodre, Michel Lavoie, Communications Research Centre - Ottowa, Ontario, Canada
Much research has been conducted in recent years on loudness perception and metering. This has been motivated by an ITU-R effort to identify a loudness measure suitable for broadcast applications. The initial ITU-R effort focussed exclusively on mono signals, and a simple loudness meter based on a weighted energy sum [Leq(RLB)] was shown to perform best. In the present paper the work on loudness perception was extended to the stereo and multichannel cases. Formal subjective tests were conducted using typical broadcast material to derive a subjective database to evaluate the performance of new loudness meters. The results were used to examine the requirements for a loudness meter for mono, stereo, and multichannel signals.
Convention Paper 6618 (Purchase now)
P17-2 The Influence of Stereophony on the Restitution of Timbre by Loudspeakers—Mathieu Lavandier, Benjamin Guyot, Sabine Meunier, Philippe Herzog, Laboratoire de Mécanique et d'Acoustique - Marseille, France
In a previous study [Lavandier et al., AES 117th Convention, 2004 Paper 6240], the restitution of timbre by loudspeakers was evaluated by perceptual and physical measurements, in order to find the link between these two parallel approaches. An experimental protocol was built that consists of recording the sound radiated by single loudspeakers in a room and then submitting the recorded sounds to listening tests under headphones. Even if the spatial dimension of sound reproduction is not investigated here, the stereophony might also influence the restitution of timbre by loudspeakers. A panel of loudspeakers is recorded in both monophonic and stereophonic reproductions. The recordings are submitted to listening tests revealing the influence of the stereophony on the perceived differences between loudspeakers. This influence turns out to be minor, and the perceptual spaces resulting from multidimensional scaling analysis of the perceived differences were not affected by the change of the reproduction configuration.
Convention Paper 6619 (Purchase now)
P17-3 Audio Processor ICs for Advanced TV—Johan Mansson, et al., Analog Devices, Inc. - Limerick, Ireland
A family of fully integrated advanced audio processors for advanced TV applications implemented in deep sub-micron complementary metal oxide semiconductor (CMOS) will be presented. These are mixed signal designs with integrated data converters and digital signal processing to enable rich acoustic experience for cost-sensitive systems. Digital performance, in terms of speed and large memory, in conjunction with low cost required by the application, calls for the use of a small geometric CMOS process. It is technically challenging to design high performance converters on such sub-micron CMOS, particular due to substrate noise and flicker noise. To overcome these issues, continuous-time converter architectures have been developed and designed.
Convention Paper 6620 (Purchase now)
P17-4 Noise Shaping in Time-Domain Quantized LFM—Malcolm Hawksford, University of Essex - Colchester, Essex, UK
SDM binary code can be derived from linear frequency modulation (LFM) using zero crossing detection and time-domain quantization. However, the jitter-like nature of this quantization process does not generally yield well-structured noise shaped characteristics compared to conventional time domain coders. The problem of improving the frequency domain performance of the error resulting from an LFM-based model is studied, and further observations are made on the relationship between SDM and quantized LFM.
Convention Paper 6617 (Purchase now)
