Tuesday, May 23, 09:00 — 10:30
Akio Ando (Chair)
P22-01 Optimization of Temporally Diffuse Impulses for Decorrelation of Multiple Discrete Loudspeakers
Jonathan B. Moore (Presenting Author), Adam Hill (Author)
Temporally diffuse impulses (TDIs) were originally developed for large arrays of distributed mode loudspeakers to achieve even radiation patterns. This initial investigation evaluates the performance of TDIs in terms of the reduction of low frequency spatial variance across an audience area when used with conventional loudspeakers. A novel variable decay windowing method is presented, allowing users control of TDI performance and perceptibility. System performance is modelled using an anechoic and an image source acoustic model. Results in the anechoic model show a mean spatial variance reduction of 42%, with a range of source material and using the optimal TDI generation methodology. Results in the image source model are more variable, suggesting that coherence of source reflections reduces static TDI effectiveness.
Convention Paper 9794
P22-02 Seamless Spatial Calibration of Multichannel Sound Systems
Antoine Peillot (Presenting Author)
In a multichannel audio setup, spatial calibration aims at delivering an optimal sound experience at the listening position. Since the listener is not expected to stand at the focal point between the surrounding speakers, usually arbitrarily placed, it is needed to focus the sweet spot at the listening position. To do so, proper gains and delays need to be applied to each channel composing the audio setup. The work presented in this paper provides a solution to automatically estimate and apply these parameters. It is based on joint user and speaker localization in a seamless way thanks to microphones embedded in surrounding speakers. A patent is currently pending for the spatial calibration method described in this paper.
Convention Paper 9795
P22-03 Extraction of Interchannel Coherent Component from 3D Multichannel Audio
Yuta Hashimoto (Presenting Author), Akio Ando (Author), Hiroki Tanaka (Author)
Extraction of interchannel coherent component is a useful method that is applicable to the improvement of blurry sound image and setting up an upmix system. In this paper we propose a new method that extracts the component from three-dimensional (3D) multichannel audio signal. Such a signal sometimes has a negative cross correlation among channels because it includes independent sounds propagated from different directions. To handle this problem, a new method is proposed to estimate the component of one channel signal by the other channel signals having positive correlations with the signal in each subband. The experimental result showed that the estimation of the component by selected channel signals brought better performance than that by all channel signals.
Convention Paper 9796