1、 Table of Contents Foreword . 1 Introduction . 1 1 Scope 2 2 Parameters 2 Annex A Bibliography 3 Foreword SMPTE (the Society of Motion Picture and Television Engineers) is an internationally-recognized standards developing organization. Headquartered and incorporated in the United States of America,
2、 SMPTE has members in over 80 countries on six continents. SMPTEs Engineering Documents, including Standards, Recommended Practices and Engineering Guidelines, are prepared by SMPTEs Technology Committees. Participation in these Committees is open to all with a bona fide interest in their work. SMPT
3、E cooperates closely with other standards-developing organizations, including ISO, IEC and ITU. SMPTE Engineering Documents are drafted in accordance with the rules given in Part XIII of its Administrative Practices. SMPTE Engineering Guideline EG 432-2 was prepared by Technology Committee DC28. Int
4、roduction For interoperability of digital cinema equipment used to deliver LFE channel audio to the playback equipment in D-Cinema environments, standardized electrical frequency response for the playback LFE channel is needed. The necessary characteristics are turnover frequency, slope and deviatio
5、n. Page 1 of 3 pages EG 432-2-2006 SMPTE ENGINEERING GUIDELINE Digital Source Processing D-Cinema Low Frequency Effects (LFE) Channel Audio Characteristics Copyright 2007 by THE SOCIETY OF MOTION PICTURE AND TELEVISION ENGINEERS 3 Barker Avenue, White Plains, NY 10601 (914) 761-1100 Approved Decembe
6、r 29, 2006 EG 432-2-2006 Page 2 of 3 pages 1 Scope This guideline addresses interoperability of equipment from the standpoint of the frequency response of filters used in the playback or monitor path in the theater LFE channel for digital cinema. This response curve will create standardization of th
7、ese filters without specifying their design. 2 Parameters 2.1 Turnover Frequency The turnover frequency is defined as the point at which the response of the filter is at 3 dB from the passband reference. The LFE channel shall have a turnover frequency of 125 Hz. 2.2 Filter Slope The filter slope of
8、the LFE Channel shall be as per the Reference Filter Response Table (section 2.4) from the turnover frequency of 125 Hz. 2.3 Deviation Deviation within the passband shall be 1 dB and the deviation of the turnover frequency ( 3 dB point) shall be 5 Hz. 2.4 Reference Filter Frequency Response Table Fr
9、equency Hz Attenuation dB 25Hz 0dB 31.5Hz 0dB 40Hz 0dB 50Hz 0dB 63Hz 0dB 80Hz 0dB 100Hz 0dB 125Hz -3dB 160Hz -45dB 200Hz -102dB EG 432-2-2006 Page 3 of 3 pages Annex A (Informative) Bibliography SMPTE 202M-1998, Motion-Pictures Dubbing Theaters, Review Rooms and Indoor Theaters B-Chain Electroacoustic Response SMPTE RP 200-2002, Relative and Absolute Sound Pressure Levels for Motion-Picture Multichannel Sound Systems Applicable for Analog Photographic Film Audio, Digital Photographic Film Audio and D-Cinema