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Publication numberUS1396402 A
Publication typeGrant
Publication dateNov 8, 1921
Filing dateJun 22, 1920
Priority dateJun 22, 1920
Publication numberUS 1396402 A, US 1396402A, US-A-1396402, US1396402 A, US1396402A
InventorsBristol William H
Original AssigneeBristol William H
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Sound-selecting apparatus
US 1396402 A
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Description  (OCR text may contain errors)



Specification of Letters Patent. I Patented Nm, 8, 1921.

- Appiieatioa fueii June 22, 1920. serial No. 390,910.

.dent of lvaterbury.

.lie it known that I, "innmrr Bizs'i'ox.,

a eitizen of lthe United States, and a resiin the eounty of New Haven and State of Connecticut,have in- -gvented certainnei'v and useful Improvements in Sound-Selecting Apparatus, of y:which the following is a specification.

` The invention relates to the reproduction ot' sound., particularly when under amplificatiomgand either direetlyf or through the thermionio' and other', amplifiers in combimedium of 'a pei'yfmanent record 'and a reproduction apparatus therefor;

..."lhe. invention is 'oneerned morepespeciallv with sound renroduetioninvolving thel use offsuper-sensitive devices such as nation-with telephonie transmitting means, for example. as more particularly set forth in my eo-pending application Serial No. 330119. In the reproduction of sound in this manner, it heeomes necessary as a result of the (extreme sensitiveness of the amplifying means to exclude all extraneous sounds, echoes and relier-tions. To this end it has lheretofiu'e been found necessary to suitably pad the walls and ceiling of the `room inv which desired Sound Waves were produced .for .recording purposes. iVhile this expedient may be satisfactory for some purposes. it of course excludes the making of records for example in auclitoi-iums churches, court-rooms and under various other conditions where it would be desirable to obtain a record of a speaker or speakers or of musical selcetions.

vwith l have found that by locating the electrical transmitting mechanism employed at the rear of a suitable protector box, which is lined with sound deadcuing material. as heavy felt or like material, that the expensive and troublesome lining of the walls and ceiling. formerly necessary. may bedispensed with and the desired sounds selected so that entirelyY satisfactory records may be obtained under conditions which have heretofore precluded the making of sueh records. l

The nature'l ol' the invention will best be understood when described in connection tho accompanying drawings. in which- Figure 1 illustrates in peijspeetire a scetional proti'ator box lor the transmitting apparatus.

Fig. 2 is a vertical section thereof. i

Similar characters of reference designate clirrespondingv parts throughout the 'Several views. '1

lefcrring to the drawings, y1() 'designates a suitably` shaped receptacle,preferably tapering. and closed throughout exceptat the. front 11 which is shown 'r'ullyfopened This reeeptacle may'he of 'various shapes, butlhave y found the fia-ring type herein illustrated particularly suitablefor the purpose. .Moreover, the box'maybe built up of removable sections, as illustrated. to readily aecommodatethe apparatus to different Con-y ditions `by 'providing the size best suited thereto. it being understood that sections V12 ai-e t0 be addedA orremoved aslrequired.

Aswill lie-noted, the'rear'of the receptacle -V is closed; and substantially at this point and in the axis of the receptacle there is located telephonie transmitting apparatus 13 of any well-known or special type. From the telephonie apparatus 13 extend leads 14 to suitable amplifying apparatus (not shown) by which the intensity of the sound is magnified to the desired extent and either reproduced directly through suitable receivers or recorded on a'phonographic disk or like member. as is well understood and which forms no particular part of the present invention.

l am aware that horns and similar' sound re.

eeiving devices have been employed` for this purpose;.but the present inventionconsists in the combination ot' a telephonie transmitter. employed in ronnertion with super-sen'- sitive amplifying apparatus. with a roteetor box or receptacle having a soun( -deadening lining such as heavy felt or similar material 15, whereby extraneous sounds will he `eliminated in the reproduction and only those desired reproduced.

ree-ted more or less toward the opening of said receptacle, although the distance from same is, within reasonable limits, variable. l have found that suitable reproduction may he obtained at convenient distances ranging, for example. from 6 to 20 feet or more from the opening of the receptacle; and in this manner it. is possible to reproduire or directly malte records as of speeches. eourt proceedings. testimony and music in the regular rooms. balls and the like in which the same are produced and without in any Way altering these places, Infact, the receptacle It is understood.' that the soumis to be reproduced will be div nl 11 is in the nature of a miniature room in which only the desired sound Waves are per v`aitted. to strike the transmitter, the others either not entering the small opening 11 at all; or, if so, beingr not reiiected to- Ward the Said .transmitter owing to the nayneous photographic reproductions oitl'e scenes accompanying theI sounds and thus admit of Synchronized reproduction of both.

I claim: 1. Apparatus for use in phonographic recording, comprisingna Haring receptacle open at the front and closed at the inner end, saidv receptacle being lined substan` tially throughout with material which will not reflect sound,'and a telephone transmitter located at theV inner end of said receptacle and acoustically independent thereof.

2. Apparatus for use in phonographic recording, comprising a flaring built-up, sectional receptacle open at the front and closed at the inner end, said receptacle being lined substantially throughout with material which will not reflect sound,`and a. telephone transmitter located at the inner end of said receptacle and acoustically independent thereof.

3. Apparatus for use in phonographic recording, comprising a flaring receptacle open at thefront and closed at the inner end, said receptacle beingjli-ned substantially,throughout with material which will not reflect sound, and a telephonie transmitter loc-ated at the inner end of said re.

ceptacle, acoustically independent thereof and its diaphragm beingwof. appreciably smaller area than the opening at the front of the receptacle. j

Signed at New York, in the .county of New York and State 'of New York, this 18th day of June` A. D. 1920. WILLIAM H. BRISTOL.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US4463453 *Dec 22, 1981Jul 31, 1984The Boeing CompanyAcoustic intensity measurement apparatus and method including probe having ambient noise shield
US4768614 *Nov 28, 1986Sep 6, 1988Case Eliot MUnidirectional enhancer for microphones
WO1988004125A1 *Nov 23, 1987Jun 2, 1988Eliot M CaseUnidirectional enhancer for microphones
U.S. Classification181/151, 181/198
International ClassificationH04R1/32, H04R1/34
Cooperative ClassificationH04R1/342
European ClassificationH04R1/34B