US1820996A - Sound amplifying system - Google Patents

Description

Sept. 1, 1931. M. WEIL 1,820,996

SOUND AMPLIFYING SYSTEM Filed Dec. 8, 1925 5 Sheets-Sheet 1 fl'j-Z INVENTOR gwh B il WK.

.MATTORNEYS Sept. 1, 1931. M. WEIL 1,820,996

SOUND AMPLIFYING SYSTEM Filed Dec. 8, 1925 5 Sheet-Sheet '2 Sept. 1, 1931. M. WEIL 1,820,996

SOUND AMPLIFYING SYSTEM Filed Dec. 8 1925 5 Sheets-Sheet 5 5 7 i i i A a 1 5 i I 21 23 In 41 m ATTORNEY5 Sept. 1, 1931. M. WEIL SOUND AMPLIFYING SYSTEM 1925 5 Sheets-Sheet 4 Filed Dec.

wfimfik $510M 1 w ATTORNEYS Sept. 1, 1931. M. WEIL 1,820,996

SOUND AMPLIFYING SY STEM Filed Dec. 8 1925 5 Sheets-Sheet 5 rllu'allhmlllllm VIIIIIII'IIIIIIIII/ W wwa Mo ATTORNEYS Patented Sept. 1', 1931 UNITED STATES MAXIHILIAN WEIL, on NEW Yonx, N. Y.

SOUND AMPLIFYING SYSTEM Application filed December 8, 1925. Serial No. 74,031.

My present invention has among its objects to provide a sound amplifying system, which will faithfully amplify vibrations corresponding to the human voice or to soft 5 or loud instrumental or other selections, without partial or complete suppression of any qualities, which will avoid any mu'filed,

. tubby, throaty or crowded effect or other distortion, and which will realistically pro-v 1 phonograph or radio loud speaker cabinets,

without alteration of the external proportions or dimensions of any of these cabinets and without the need for doing away with or reducing the volume of the record compartment or the radio panel compartment commonly employed in cabinet constructions of the types referred to.

Accordingto my invention, the amplifying system within the cabinet is enlarged by the use of doors or wings preferably at the side walls of the cabinet, which may open outward to form an enlarged amplifier mouth, greater in width than the cabinet. The instrument being placed obliquely in the corner of a room as usual, the open doors will subtend the angle between the walls that form the corner of the room, so that the wave front will spread substantially uniformly throughout the volume of the room.

Preferably, the wings aredoors hinged at the side walls of the cabinet, and flush therewith when closed, to provide a cabinet of-conventionaldimensions. It is desirable to provide these doors with end pieces which close the gap between the cabinet side walls and the upper and lower edgs of said wings in any open position, thereby providing a substantially continuous wall for the mouth of the amplifier system in any and'all ad- 'justments, in which it may be desirable to use the instrument.

My system in its preferred application is of the type which includes anamplifying horn and an amplifying reflector, the latter facing the mouth of the former. According to my invention, the mouth of the horn has one dimension much larger than the other and the .reflector which preferably extends at least the full length or width or the longer dimension of the horn mouth diverges out- Wardin the direction of the smaller dimension of the horn mouth. In one preferred embodiment, the horn is rectangular in crosssection and has its main divergence in a vertical direction or dimension, while the amplifying reflector has its divergence in horizontal direction. The wave front expands in two phases, first in one direction or dimension and then in the direction or dimension at right angles thereto.

In the accompanying drawings in which are shown one or more of various possible embodiments of the several features of the invention,

Fig. 1 is a perspective view with parts broken away showing one application of the invention with the Wings open,

Fig. 1a shows the appearance of the instrument when the wings are closed, so Fig. 2 is a View thereof in longitudinal cross-section on a larger scale,

Fig. 3 is a plan view with the cover removed,

Fig. 4 is a sectional view on a reduced scale taken along the line 4-4 'of Fig. 2,

Fig. 5 is'a sectional view on a reduced scale taken along the line 55 of Fig. 2, but showing the wings open,

Fig. dis a sectional view on a reduced scale taken along the line 66 of Fig. 2, also showing the wings open, and indicating in dot and dash lines the throat of the amplifier,

Fig. 7 is a sectional view taken along the line 77 of Fig. 5,

Fig. 8 is a view similar to Fig. 6 of a modification,

Fig. 9 is a front View of another embodiment, primarily for radio application,

Fig. 10 is a fragmentary view similar to Fig. 2 showing another application for phonographic use,

Fig. 11 is'a section on a reduced scale taken on the line 11-11 of Fig. 10, and;

Fig. 12 is a perspective view indicating an ap lication as a radio loud speaker.

11 Figs. 1 to 7, I have illustratively shown a preferred embodiment'of sound amplifying system adapted for and employed in a phonograph construction of substantially conventional external dimension. The phonograph shown may be provided illustratively with doors 10 commonly used, or their equivalent, at the upper part of its front wall 11 and includes the rear wall 12, side walls 13 and the hinged cover 14, which, when open, discloses the motorboard 15 with the turntable 16 and the tone arm 17 thereon.

The amplifying system within the cabinet includes a horn it having its throat 18 immediately below the motorboard near the rear thereof, said horn extending downward substantiall along said rear wall and thence dia onally orward as shown at 19 and prefera ly diverging therebeyond at an increased angle as best shown in Fig. 2 with its mouth near the rear of the cabinet and opening rearwardly. a

In a preferred embodiment, the horn is rectangular in cross-section and comprises preferably a pair of vertical plane side walls 20 and 21 connected by .a pair of transverse walls, both straight in transverse section and curved in longitudinal section, the upper and forward one of said walls being shown at 22 and determining the upper border 22' of the rectangular mouth, the lower and rear one of sai greater length, as shown, its outer edge 23' determining the'lower border of the mouth of the horn. Preferably, the jointsor con-,

nections between the walls are substantially tight throughout the length thereof, so that no sound leaka will take place by way of the corners o the. horn. The transversewalls of the horn may be designated cylindrical since they are determined each by a straight generatrix moving along a curved pa As shown in the drawings, the curved transverse walls of the horn diverge widely from the throat to the month, while the vertical plane walls .20 and 21 have but little diver ence as best indicated in Fig. 6, the mout of the horn being thus in the form of a rectangle of substantial height but of small width.

The horn delivers into an amplifying reflector 24 facing and to the rear of the mouth of the horn, said reflector having a median vertical cusp 25 and having a vertical wall of generally arcuate horizontal cross-section terminatin at the side walls 13 ofthe cabinet. Pre erably, but a small walls 23 being of considerably gap in the order of a couple of inches is left between-the vertical edges of the mouth of the horn and the surface of reflector 24. Doors 26 are hinged at the side walls of the cabinet at the outer ends of the fixed reflector portions and when in normal or closed position extend flush with or constitute parts of the side walls of the cabinet, which then has the conventional appearance, size and dimensions of an ordinary phonograph cabinet.

When the doors 26 are opened, as best indicated in Figs. 5 and 6, the lengths thereof constitute extensions or wings of the amplifying reflector wall with advantages that will appear hereinafter. It is preferred to form rigid with the doors, horizontal end pieces 27 and 28 both at the top and bottom thereof, which as best shown in Fig. 7 slip into corresponding slides therefor in the cabinet wall. Preferably, the cabinet for this purpose is provided with a floor immediately above its legs Z consisting of two parallel partitions 29 and 30, leaving a space 31 therebetween into which the lower door ends 28 are adapted to extend and similarly there are provided a pair of parallel transverse partitions 32 and 33 immediately above the amplifying reflector 24 leaving therebetween a space 34 somewhat wider than that between the bottom partitions to accommodate a stop cleat or enlargement 35 formed at the inner edges of the upper door ends'and arrested by the inner face of the corresponding fixed cabinet side walls to limit the opening of the doors.

As best shown in Fig. 2, the arrangement described aii'ords ample room above the partition 33 for a record compartment with vertical partitions 36 accessible by opening the front doors 10, the upper part of the horn extending well. to the rear of the record compartment. The honograph motor 37, as best indicated in Fig. 4, would be disposed in a compartment therefor preferably midway between the record housing compartments.

The partitions 32 and 33 must, of course,

be provided with openings through which the horn It extends. These preferably afford a small clearance 38 with respect to rectangular panels are easlento make, easier' to install and afiord a more substantial mechanical support for the curved transv 29, the lateral verse walls 22 and 23 that are secured therebetween, than would panels cut or formed to follow the curvature of said transverse horn walls. For additional mechanical support, a sustaining wall orstr-ut is provided, extending across and secured at the forward edges of thepanels 20 and 21 and attached at its upper end to the outermost curved part of the rear wall 23 of the horn. In order to avoid resonance in the wedge shaped air space enclosed between the floor anels 20 and 21, the transverse wall 23 o the horn and the sustaining wall 40, the latter is preferably provided with a series of apertures 41.

The tone arm 17 may be of conventional construction, including a pivot or' swivel mount at the motorboard. It is desirable to form this swivel mount substantially airtight, for which purpose, I employ a tone arm base 42 with integral internal circumferential ridges 43 which encircle the bearing shank 44 of the tone arm with a close but low-friction fit.

The tone arm is illustratively shown in Fig. 3 of curved construction and has mounted at the outer end thereof, the gooseneck construction 45 carrying the sound box 46 and illustratively pivoted in place by providing the tone arm with an enlarged cup portion 47 affording a snug but low-friction fit about the end of the goose neck. A set screw 48 extends through a slot 49 in the tone arm and into a corresponding de- -l= pression (not shown) in the goose neck and serves to prevent the latter from coming off.

By my invention, a substantial efl'ective length of horn is accommodated within the conventional cabinet, as set forth, without increasing the Width, depth or height thereof, by dividing said born into two elements affording successive stages of amplification, the mouth of the horn h extending, and delivering into the amplifying reflector 24 and, moreover, coacting therewith in the final-stage of amplification, in the manner already set forth. The doors or wings 26 open in the wedge space availablev between the side walls of the cabinet and the walls of the room, to afford a mouth far wider than the width of the cabinet. When the instrument is out of use, the wings or doors are closed flush with the side walls of the cabinet, which then has the conventional compactness of an ordinaryclosed phonograph cabinetn In use of the instrument with the doors 26 open, the wave front of the sound vibrations from the tone arm, passes downward through the horn h and thence rearward through the mouth thereof. The wave impinges, as best shown in Fig. 6, directly upon the central part of the amplifying reflector 24, dividing at the cusp-25 thereof and thence the wave front diverges and advances in a generally horizontal direction into the room. 4

When, as usual, the instrument is placed diagonally in a corner of the room, the open wings or doors constituting the mouth of the amplifier system, subtend practically the entire angle of the corner of the room, so that the sound is projected into the room, along and throughout the angle between the walls of the room that form the corner. Thus, regardless of where the auditor may be positioned in the room, he always is in line with the open mouth of the amplifier and becomes aware of no noticeable differences in volume at different parts of the room. The sound, accordingly, does not appear to come from a restricted source, but the expansive or space effect of an orchestra or a band, for instance, is realistically reproduced, the sound appearing as in the original production, to have its source over a wide area. I

WVith my amplifying system, selections of all types, vocal or instrumental are ampli' fied substantially without distortion, and suppression of any of the tones is obviated.

While, as noted, the best results are obtained more especially in playing a powerful selection, for instance, one including many instruments, when the doors 26 are opened wide, as best shown in Fig. 6, yet with selections of lesser volume, although the doors may with good results be kept wide open, the user of the instrument can vary theposition or setting of the doors and with soft selections for instance, violin solos, it may even be desirable to close the wings or doors entirely, for minimum width of amplifier mouth and minimum divergence I the angle of divergence between the lateral walls of the mouth of the system.

It have thus provided an amplifier system operative in itself, even where the doors or wings are closed, the latter serving as a superadded structure for enlarging the width of amplifier mouth and the divergence between the walls of said mouth with the re: sults already noted.

It will be-noted that the outer faces of the side walls 20 and 21 of the horn within the amplifying reflector diverge with respect to the reflector wall and the wings thereof,

to form a horn with walls diverging in a horizontal plane, the floor ,29 with the lower door end piece 28 forming the lower wall of 1 the side walls. of the horn and the reflector merge in the cabinet in front of the horn wall 23.

The reflector wings 26, it will be noted, are of height somewhat greater than the central or stationary part of the reflector, and the edges of the fixed top and bottom walls of said reflector are preferably beveled as shown, to provide a slight divergence in a vertical direction from the cusp of the reflector to the end pieces of the reflector wings.

The wave front from the tone arm to the mouth of the cabinet, is caused to advance for divergence first essentially in one plane or in one dimension of its area, in this case vertically, and then to diverge essentially in the plane or dimension at right angles thereto, in this case, horizontally.

An instrumentactually constructed in accordance with the disclosure of Figs. 1 to 7 was found to perform in actual practice according to the foregoing description.

In Fig. 8 is shown a modification in which the rear corners of the phonograph cabinet are beveled at 60, so that whenthe instrument is in its usual corner position, the

doors 61 when open would not only as in Fig. 1 subtend the angle between the walls forming the corner as shown, but they extend as shown, substantially parallel to or along the walls of the room rather than merely approximately so, the walls of the room constituting extensions of the reflector wallor wing. While, as shown in this embodiment, wings or panels 61 may be employed devoid of the end pieces. shown at 27 and 28 in Fig. 7, the results are in gencral superior when "such pieces are present. Except as above specifically described, the embodiment of Fig. 8 may be identical with that of Figslto 7. a p

In .Fig. 9 is shown an application of my sound amplifying system in a radio receiving set embodied illustratively in this case in a highboy type of cabinet. This cabinet has the amplifying reflector as in Fig. 1 with wings or. doors 71 in the side walls. The radio panel 72 is mounted above the reflector as shown immediately below the top of'the cabinet. To the rear of the radio panel is mounted the telephonic element 73 which is secured in sound-tight relation to the throat of the horn 74 .correspondingto the horn h indicated merely in dotted lines extending forward, thence curvin back to deliver rearward into the ampli ying reflector, through a rectangular mouth 74 of height corresponding to that of the reflector 70-as in the embodiment of Figs. 1 to 7.

In Figs. 10 and 11 is shown illustratively a phonographic application of alternative construction in which the record compartment 75 is at the lower part, being separated by transverse partitions 16 from the amplijacent the tone arm 83, the desired length of horn is accommodated in the small space 71 available by extending the small or throat end 84 of the horn lengthwise through the space 85 between the rear wall 86 of the cabinet and the cusp of the reflector.

The horn curves forward and upward from below the reflector and partitions 76 to near the front wall of the cabinet, and thence diverges to a narrow rectangular mouth as in Fig. 1, of substantially the height of the reflector, and opening rearward to deliver thereinto. As in theembodiment of Figs. 1 to 7, the lateral walls 88 of the horn are preferably plane, and the transverse walls thereof curved into cylindrical surfaces, the outer part of the lower curved wall being sustained by a strut or panel 89 correspondi112 to strut 40 in Fig. 1.

In Fig. 12-is shown a pers ective view of an application of my amplig'ing s stem to a ca inet type of radio'loud spea er. In this case, the rectangular cabinet 90, as in the other embodiments, is provided with the hinged doors or wings 91 of an am lifying reflector 92. The telephonic spealier element 93 is near the front of the cabinet and the horn 94 extends horizontally rearward from its throat and thence is sharply curved forward at 95 toward the front of the cabinet and from there doubles back again with substantial divergence in the direction of the height of the cabinet to a month which opens rearward to deliver against thecus (not shown) of the reflector. The mout of the horn in this case as in Figs. 1 to 7 has preferabl its maximum dimension of the eight 0 the amplifying reflector 92 which, in turn, is of the maximum height available within the cabinet. As in Fig. 1

a strut 96 sustains the outer part of the longest wall of the horn.

In all of the embodiments, I have shown a horn rectangular in cross-section, with flat panels forming the larger dimension of the cm near the switch. thereof. This construction is preferred because it economizes materlal and labor and producesusatisfactory results- It is possible, however, within the scope of my invention from its broader aspects, to employ a.-horn of a wide variety of cross-sections angular or curved.

\Vhile in all embodiments, have shown the horn with lateral walls diverging slightextensions.

ly, it will be understood that these could be made parallel so that all of the divergence of the horn is in one direction, the amplif ing reflector thereupon producing the ivergence of the wave front in a direction at right angles thereto.

Any of the phonograph constructions shown may be used as radio loud speakers for which purpose, the sound box would merely be replaced by a telephonic element, although other special constructions not requiring replacement could be used to advantage.

I claim:

1. A sound amplifying system including a sound reproducer, an amplifier horn having a small inlet and diverging to a mouth materially larger in one dimension than in the other and delivering into a reflecting amplifier section having walls diverging mainly in a plane substantially at right angles to the plane of larger dimension of said mouth.

2. A sound amplifying system including an amplifier horn having a small inlet and diverging to a mouth -materially larger in 'one dimension than in the other and a reright angles to thatof the maximum dimension of said mouth.

4. A sound amplifying system including a sound reproducer, a horn communicating therewith including a pair of plane panels forming opposite walls of the mouth portion thereof and a reflector facing the mouth of said' horn and having diverging walls presenting an apex at the mouth of the horn to divide the wave front for further amplification of the sound waves emanating from said horn, said reflector walls having movable 5. A sound amplifying system including a sound reproducer, a horn communicating therewith including a pair of diverging plane walls forming the lateral walls of the mouth portion thereof, a reflector facing the mouth of said horn, said reflector being of substantially the height of said mouth shaped to divide the wave front and having laterally diverging movable walls for further amplification of the sound waves emanating from said horn, the outer faces 7. In a generally rectangular sound amplifying cabinet, a sound reproducer, an amplifying system communicatin therewith and including a horn extending substantiall the length of one dimension of the cablnet and a diverging flat walled month portion in sound conducting relationship with the larger end of said horn, said mouth portion including a wall opening outward from one of the walls of the cabinet and including end pieces at right angles thereto adapted to slide within t e cabinet.

8. In a sound amplifying cabinet, a sound reproducer, an amplifylng system communicating therewith and having a horn structure extending substantially the height of said cabinet and a diverging flat walled mouth portion in sound conducting relationship with the large end of said horn structure, said mouth portion including a wall opening outward from the side wall of said cabinet.

9. In a sound am lifying cabinet, a sound reproducer, an amp ifying system communicating therewith and having a fixed horn structure and a diverging mouth element in sound reflecting relationship with the larger end of said horn structure, said mouth portion including a pair of movable extensions openin outwardly from the lateral walls of said ca inet.

10. A sound amplifying system including a cabinet, a sound reproducer near the top of said cabinet, an amplifier horn having a pair of plane vertical lateral walls and a pair of curved diverging walls extending therebetween anddetermining a mouth of substantial height and of small width opening to the rear of the cabinet, and an amplifylng reflector in back of the mouth of said horn, said reflector having a pair of wings ada ted to be disposed in the plane of the cabinet wall and to be opened to providean outlet in operation of width greater than that of the cabinet.

11. A sound amplifying system including a horn generally'rectangu ar in cross-section having a pair of plane vertical side walls diverging symmetrically and upper and lower curved walls of substantial divergence, a cylindrical amplifying reflector of symmetrical form havin its middle part facing the mouth of sai amplifying horn and affording small clearance with res ect to the vertical walls thereof, said amplify- -3 of said mouth of height substantially that of said mouth and including an outer pivoted laterally adjustable wing to vary the area of the mouth of said reflector.

13. A phonograph cabinet including a e a motorboard, a tone arm pivoted thereto,

an amplifying horn connected with said tone arm and extending downward therefrom' and having a mouth opening rearward, an amplifying reflector 1n sald cabinet extendi ing in backof said mouth and having adjustable wing panels pivoted at the side walls of said cabinet.

' extending in back of said mouth and having adjustable wing panels, pivoted at the side walls of said cabinet, said wings having slide portions at right angles thereto extending into corresponding spaces therefor provided within the cabinet.

15. A phonograph system including a cabinet, a motorboard, an amplifying horn of substantially the height of said cabinet ex tending from said sound reproducer, said horn including a pair of vertical diverging plane panels determining the lateral walls of the outer or month end of the horn, said horn including upper and lower curved walls of substantial divergence, extending at their 1 outer parts in sound-tight relation between said vertical walls, a symmetrical amplifying reflector in said cabinet of substantially the height of said mouth extending at itsv central portion in back of said mouth and 5; diverging forward therefrom to the side walls of the cabinet, and diverging panels extending outward from the side walls of the cabinet and constituting wings gfisaid reflector, a

cabinet having a motorboard, a tone arm pivoted thereto, a sound amplifyingsystem including a horn having a throat in substantlally sound-tight connection with said B66 tone arm, said horn extending generally downwardly substantially the entire height of the cabinet and having a rearwardly opening mouth at the lower part of said cabinet, and an amplifying reflector in said cabinet of substantially the height of the mouth of said horn and having forwardly opening diverging walls, and a record com:

partment betweenthe motorboard and the amplifying reflector. I

17. A sound amplifying system including a cabinet, a motorboard, an amplifying horn of substantially the height of said cabinet extending downwardly from said motorboard, said horn including a pair of vertical diverging panels determining the lateral walls of the outer or mouth end thereof, said horn including an upper and a lower curved wall of substantial divergence ex-' tending at their outer parts in sound-tight relation between said vertical panels, a symmetrical amplifying reflectorin said cabinet and of substantially the height of said mouth extending at its central portion in back of said mouth and diverging forward therefrom to the side walls of the cabinet, and hinged doors constituting wings of said amplifier when in open position, said/doors adjustable in position to vary the effective width of the outer part of the reflector.

18. In a sound amplifying cabinet, in combination, a sound reproducer, an amplifying system for the sound waves emanating therefrom, said system including an ad]ustable diverging mouth, comprising a pair of hinged wings extending flush with opposite walls of the cabinet when closed and including end pieces extending rigid therewith at right angles thereto to determine corresponding walls of the mouth when the wings are open, said cabinet havin pairs of spaced transverse partitions a ording slides for said wings, and a stop for limiting outward movement of the wing.

19. In a sound amplifying cabinet, in combination, a horn having a mouth opening rearward, an amplifying reflector of substantially the height of said mouth having its central portion in back of said mouth,

said reflector including adjustable lateral wlngs constituting when in closed position parts of the side walls of the cabinet, said wings having slide portions at right angles thereto determining the upper and lower walls of the reflector, said cabinet having transverse pairs of partitions determining spaceswithin which said slide portions are guided and lodged.

20. In a sound amplifying system, in com- I a bination, a horn having a diverging neck 16. Aphonograph structure inehdl'iiga' portion and a more widely diverging mouth portion unitary therewith, said horn being rectangular in cross-section and including a pair of rectangular vertical lateral walls and a pair of curved walls extending therebetween and secured thereto in sound-tight relation and having substantial divergence therebetween, a sustaining panel between said vertical walls supporting the outermost portion bf the longer curved wall, said panel hav ng one or more ports therethrough to obviate resonance efiects.

21. In a phonograph cabinet, in combination, a motorboard, a transverse partition spaced below the motorboard and defining the bottom of a record compartment, and the top of an amplifying reflector compartment, and an amplifying horn extending downwardly from said motorboard in back of said record compartment transversely through said partition and having a mouth opening rearwardly to deliver into the amplifying reflector, the wall of said horn being spaced from said transverse partition.

22. In a phonograph cabinet, in combination, a motorboard, a transverse partition, a record compartment between said motorboard and said partition, an amplifying reflector compartment below said partition, an amplifying horn extending downward from said motorboard in back ofsaid record compartment transversely through said transverse wall and having a mouth opening rearwardly to deliver into the amplifying reflector, the wall of said horn being spaced from the transverse partition, said amplifying reflector including a pair of adjustable lateral wings constituting in closed position parts of the side walls of the cabinet.

23. A sound amplifying cabinet structure including a sound re roducer, an amplifying system within said cabinet, and a pair of hinged wings at the sides of said cabinet, determining the outer part of mouth of the amplifying system, the rear wall of said cabinet being beveled along its vertical edges so that when the apparatus is disposed crosswise 1n the corner of a room and the wings are open, the latter will extend substantially parallel with the corresponding walls of the room.

24. In apparatus of the character described, in combination, a generally rectangular cabinet, a sound amplifier within said cabinet having a mouth opening forwardly of said cabinet and a pair of wings at the side walls of said cabinet adapted to be opened for enlarging the effective width of the mouth of the amplifier, whereby with the cabinet standing in the corner of a room, the open amplifier mouth will subtend substantially the full angle of the corner of the room and the wave front from the apparatus will advance with substantially uniform intensity throughout the area of the room.

25. In apparatus of the character described, in combination, a generally rectan- 26. In apparatus of the character described, in combination, a generally rectangular cabinet, a sound amplifying system therein having a mouth opening forwardly of the cabinet, side walls having hinged wings or panels substantially flush therewith, constituting substantially the lateral walls of the mouth and adapted to be moved outward through a variable angle for widening the effective mouth of the amplifier system and varying the angular relation between said wings at will, and means movable with the upper and lower edges of said wings to close the gap between the same and the stationary side walls of the cabinet in all settings of said wings.

27. A sound amplifying system including a stationary amplifying horn and a reflector having three sections, including a fixed central section facing the mouth .of said horn and wing sections movablefor varying the angular relation thereof with respect to the stationary horn.

28. A sound amplifying rectangular cabinet having an amplifying horn therein with a rearwardly extending mouth, a stationary reflector in said cabinet facing said mouth,

parts of the side wall of said cabinet adjacent said reflector being hinged and adapted to be opened outwardly to form extension wings of said reflector.

29. In an amplifying system, in combination, a cabinet, an amplifying horn therein, a reflector including fixed sections facing the mouth of said horn, wing sections larger than said fixed sections and including end pieces substantially straddling the stationary reflector wall therebetween.

Signed at New York in'the county of New York and State of New York.

. MAXIMILI'AN VVEIL.

gular cabinet,-a sound amplifying system therein having a mouth opening forwardly of the cabinet, side walls having hinged wings on panels substantially flush therewith, constituting substantially the lateral walls of the mouth and adapted to be moved outward through a variable angle for widening the effective mouth of the amplifier system and varying the angular relation between said wings at will.

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