AES 東京コンベンション 2009
Paper Session A4

A4 — ディジタルオーディオ機器とメディア

Saturday, July 25, 9:15 — 10:35
座長: 守谷 健弘 (NTT)

A4 - 1   サンプリングジッタのリアルタイム測定ソフトウェア

西村 明(東京情報大学)
This paper presents a real-time software of sampling jitter measurement. The software is programed on the MATLAB environment using the data acquisition toolbox to get analog-to-digital converted audio signals in real-time. It can display a jitter waveform and its spectrum. It can also display an amplitude fluctuation waveform and its spectrum, which is often observed as a result of conversion process in a DAC or an ADC. The beneits of the real-time jitter measurement are discussed in terms of the factors truly or not truly affecting jitter and the professional use of the digital audio equipments.

A4 - 2   MPEG−4 ALSによるライブハウスにおける演奏音のロスレス伝送

鎌本優(日本電信電話株式会社,NTT コミュニケーション科学基礎研究所), 原田登(日本電信電話株式会社,NTT コミュニケーション科学基礎研究所), 守谷健弘(日本電信電話株式会社,NTT コミュニケーション科学基礎研究所), 金順暎(日本電信電話株式会社,NTT 未来ねっと研究所), 藤井竜也(日本電信電話株式会社,NTT 未来ねっと研究所)
This paper reports an experimental result of lossless transmission of sound data. Sixteen-channel acoustic signals compressed losslessly by MPEG-4 ALS were transmitted from the live house to the cafeteria via IP network in order to provide high-quality music. At the cafeteria, received sound data were decoded perfectly and appropriately remixed for adjusting to the environment of the location. Combination of high-definition video and audio data enables more fans to enjoy the performance of the musicians not only in live house but also in any other places at the same time. The experimental result shows that sound data are successfully compressed to around 38% of its original size losslessly, and the ALS can save the data rate about 11 Mbps.

A4 - 3   Audio Archive Technology: Now and the Future

Matthew J. O'Donnell (BSkyB R&D)
Audio and broadcast archive warehouses require scalable storage technology which is expandable, robust and with fast enough access for synchronous read, write and transmit operations. The archive technology chosen by an organization is likely to be a multi-tiered system comprised of different storage mediums, each with their own strengths. This paper investigates the storage options for broadcast and audio archiving, and details opportunities for the future.

A4 - 4   M/S Techniques for Stereo and Surround

Helmut Wittek (SCHOEPS Mikrofone GmbH, Karlsruhe, Germany)
Coincident microphone setups are well known for their unique flexibility in terms of stereophonic imaging. How-ever, their reputation in terms of their spatial reproduction is bad. This prejudice was produced both by non-optimal setups having insufficient signal separation and non-optimal microphones of the 60s and 70s. These shortcomings nowadays can well be avoided. Coincident setups and, in particular, M/S setups for Stereo and Surround exist that are popular for their outstanding practicability. When care is taken regarding parameters like directional imaging and diffuse field correlation, a coincident setup can compete with spaced setups also regarding the spatial reproduc-tion. A particular look is taken on the Double M/S technique for Stereo and Surround.

Last modified: Mon Jun 22 20:48:00 2009