1、f-?,- - EIA 38b 71 m 3234600 00b700L 7 m EIA STANDARD Recommended Measurement Method for Phonograph Rumble RS-386 Engineering. Department EIA 38b 71 W 3234b00 00b7002 9 -* . 1s NOTICE EIA engineering standards are designed to serve the public interest through eliminating mis- understandings between
2、 manufacturers and purchasers, facilitating interchangeability and improve- ment of products, and assisting the purchaser in selecting and obtaining with minimum delay the proper product for his particular need. Existence of such standards shall not in any respect pre- clude any member or non-member
3、 of EIA from manufacturing or selling products not conforming to such standards, nor shall the existence of such standards preclude their voluntary use by those other than EIA members whether the standard is to be used either domestically or internationally. Recommended standards are adopted by EIA
4、without regard to whether or not their adoption may involve patents on articles, materials, or processes. By such action, EU does not assume any liability to any patent owner, nor does it assume any obligation whatever to parties adopting the recommended standards. . Published by ELECTRONIC INDUSTRI
5、ES ASSOCIATION Engineering Department 2001 Eye Street, N.W., Washington, D. C. 20006 Electronic Industries Association 1971 Ail rights reserved PRICE: $1.00 Printed in U.S.A. /- EIA 386 71 M 3234600 0067003 O RS-386 Page 1 RECOMMENDED MEASUREMENT METHOD FOR PHONOGRAPH RUMBLE (From Standards Proposal
6、 No. 1 O 70, formulated under the cognizance of EIA Working Group P-8.2 on Phonograph Components and Records.) (References: I. “NAB Standard, Disc Recording and Reproducing, March, 1964” 2. German DIN 45-538139 DIN 45-544) I. SCOPE 1.1 The purpose of this standard is to describe a method of phonogra
7、ph rumble measurement for purposes of correlation and specification of phonograph rumble level on a laboratory basis. The measurement reflects the electrical effect, not necessarily the aural annoyance value, of phonograph rumble. 2. DEFINITIONS 2.1 Phonograph Rumble is the vibrational motion as mea
8、sured by the cartridge with the stylus engaging an unmodulated record groove and caused by the phonograph operating mechanism. 3. TEST EQUIPMENT 3.1 Rumble Test Stand. The Rumble Test Stand shall comprise a mounting arrangement such that the phonograph mechanism can be mounted by the normal means pr
9、ovided to a fixture isolated from strong electric and magnetic fields and from excessive airborne or building vibrations. 3.2 Rumble Test Record. The Rumble Test Record shall be a 12 inch 33-1/3 rpm record conforming to EIA Standards and having an unmodulated area near the outer edge for rumble meas
10、urement. In addition, the record may contain right, left, and lateral signals for reference purposes, or different records may be used to establish reference levels. 3.3 Rumble Measuring Equipment 3.3.1 Rumble Curve. A wave analyzer, of approximately 1/10 octave band pass, shall be used to produce a
11、 rumble response curve from 20 to 500 Hz with a suitable graphic level recorder. Pen speed shall be sufficiently high and sweep time sufficiently long, that any periodic peak shall be accurately recorded in level and frequency. O .- EIA 38b 71 3234600 00b7004 2 RS-386 Page 2 3.4 Signal Reference Lev
12、els. Shall be established on the curve with the wave analyzer in an “all pass” posit ion. 3.5 Noise Level. The Rumble Measuring Equipment Noise Level, with phonograph pickup, amplifier if used, and wave analyzer connected, must be at least 20 dB below the rumble curve between 20 and 500 Hz. 4.1 4.2
13、4.3 4.4 4.5 4.6 5.1 4. TEST PROCEDURE Mount phonograph mechanism as designed. Place rumble test record on spindle with concave side if any, toward turntable. Connect power and signal cables. Phonograph mechanism must be at or above 68 deg. F. Start phonograph and cycle, where applicable, to start te
14、st. Set reference levels and read out rumble in any portions of outer 1/2” margin or record grooves. 5. REPORTING DATA Equipment Specification. For correlation purposes all items pertinent to rumble must be specified, such as wave analyzer used, line voltage, cartridge, electrical loading, phonograp
15、h options and rumble reference level. 5.2 Frequency Response. A curve or tabulation of the phonograph frequency response in the range of interest. Identify the test record used for this measurement. 5.3 Noise Response. A curve of the noise in the range of interest with the phonograph motor running a
16、nd the tone arm in the rest position. 5.4 Rumble and Reference Level. A curve of the Rumble in the range of interest preceded or followed by a recording of the rumble reference level. State the frequency of the rumble reference level signal. Note: It is recommended that the reference frequency be 1 O0 Hz.
