1、v i m EIA 331 bb = 3234600 00b5b35 T /- /e-=- EIA STANDARD Polarization of Stereophonic Headphones with 3- Contact Plugs RS-331 a December 1966 Engineering Department ELECTRONIC INDUSTRIES ASSOCIATION NOTICE EIA engineering standards are designed to serve the public interest through eliminating mis-
2、 understandings between 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 a
3、ny member or non-member of EIA from manufacturing or selling products not conforming to such standards. Recommended standards are adopted by EIA without regard to whether or not their adoption may involve patents on articles, materials, or processes. By such action, EIA does not assume any liability
4、 to any patent owner, nor does it assume any obligation whatever to parties adopting the recommended standards. Published by ELECTRONIC INDUSTRIES ASSOCIATION Engineering Department 2001 Eye Street, N.W., Washington, D. C. 20006 0 Electronic Industries Association 1966 AU rights reserved Price $.O P
5、rinted in U.S.A. I EIA 331 bb 3234600 ilOb5617 3 H c_ RS-33 1 PAGE 1 POLARIZATION OF STEREOPHONIC HEADPHONES WITH 3-CONTACT PLUG O (From Standards Proposal No. 831 formulated under the cognizance of Subcommittee P-8.5 on Loudspeakers and Loudspeaker Parts) 1. BACKGROUND Some stereophonic headphones
6、are constructed, because of the shape of the ear cushions, to fit the wearer only one way. That is, left phone fits the left ear, and right phone fits the right ear. It is intended that each stereo channel, left or right, be reproduced at the corresponding ear. Even where the cushions may fit either
7、 ear, it is desirable that the user know which channel either phone reproduces in operation. 2. SCOPE This Standard is intended to specify the jack and plug wiring for proper polarization and channel reproduction. It is also intended to specify phones marking for left and right when they are marked.
8、 This Standard covers only headphones using a 3-contact plug similar to Figure 1. It does not apply as such to amplifier, tuner and other equipment using the jack, but these equipments must be wired correspondingly if phones are to reproduce left and right channel, with proper polarization, at corre
9、- sponding left and right ear. 3. STANDARD CONNECTIONS The following connections are standard: Barrel Ring TiP Common Left phone Right phone 4. STANDARD POLARIZATION The following polarization is standard: The individual phones shall be polarized so that diaphragms move toward the listeners ear when a positive potential is applied to tip or ring, with negative return to the barrel. 7/13 Figure 1 (No tolerances are specified here.)
