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A study of 3-dimensional sound field reproduction technique based on the reflective audio spot

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Yutaro Sugibayashi$Sota Kurimoto$Masanori Morise$

Takanobu Nishiura$Fumihisa Shibata$and Hideyuki Tamura

1) )?[gXgX! })X&fJ

J) 525-8577 "l)pETn)l 1-1-1K

Abstract : We have constructed a audio-visual mixed reality (MR) system with headphones%In

this paper, we try to construct a new 3-dimensional sound field reproduction technique, named

”acoustic planetarium” with several parametric loudspeakers. Parametric loudspeaker can emit the

acoustic sound wave to a particular area. Furthermore, acoustic sound image is perceived on the

wall, provided that the emitted sound wave arrives at listeners through the wall. Utilizing proposed

technique, the users can experience 3-dimensional sound fields without headphones. We carried

out evaluation experiments for the proposed technique. And we confirmed the effectiveness of the

proposed technique.

Key Words: Mixed Reality, 3-Dimensional Sound Field Reproduction, Parametric Loudspeaker

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Loudspeaker amp. YAMAHA$P2500S

Microphone amp. audio-technica$AT-MA2

D/A converter Roland$UA-101

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