US2096113A - Sound recording and reproducing - Google Patents

Description

J. R. KlEL V SOUND RECORDING AND REPRODUCING Oct. 19, 1937.

3 Sheets-Sheet 1 Filed Sept. 19, 1935 Oct. 19, 1937.

J, R. KIEL SQUID RECORDING AND REPRODUOING Filed Sept. 19, 1935 3 Sheets-Sheet 3 jaw/m- Patented on. 19, 1937' I UNITED STATES PATENT OFFICE sown anconnnve AND ammo John Ripley me, Chicago. at,

c p ra Chicago. Ill, a at tion, Illinois -01 Ripley Application September 19, 1935, Serial No. 41,189

zzclaims.

An oblect oithis invention is to provide an improved apparatus tor recording sound by means of a groove on along strip or ribbon. hereinafter referred-to as a film, of a suitable permanently dc- 5- i'ormable material, whether -coated or uncoated. and for reproducing sound therefrom. Another oblect is to provide an improved film carrying a plurality of parallel grooves by which a continuous sound record is. made reading in op.- posite directionsln alternate grooves.

' These and other objects, as will hereinafter appear. are accomplished by this invention which is fully described in the following specification and shown'in the accomp nyin drawings, in which- Figure l is a front elevation oi a machine embodying this invention:

Fig. 2 is a partial enlarged vertical section on theline 2 o! l'ig. l:

mdisaverticalsectiononthelinel orr'ig.2;'

Iao l'imdisai'rontelevationoiastripoffilmhav- 26 tionary anvil beneath;

fig. 6 iso partial enlarged vertical section on ing sound grooves produced by paratiu; I

'Ilg.5 -isancnlargedsectionotfiimonthe line.

showingthesta-- I of m. 4 and'line coring. '1,

. thelineiotlignand l 'ig. 'lisaverticaisectionontheline'lotl 'lmd.

This in. continuation in portal my pending an.

80 plications Serial No. 859.838, filed March 3, 1933. showing a rigid. stationary support over which the film is slid at the print record n and Serial No. 685,145, flied August 14, 1933, showing a mechanism tor propelling an endless him having a plu- 36 rality 01 parallel sound grooves therein past a reproduces pick-up. together with means operated by notches on the sides of the film (or controlling. the movuneut oi the film'and for shifting thereproducer pick-up from one groove in the film to of cellulose acetate. cellulose nitrate. orother permanently deicrmable material, either with, or

without an emuisiom'aa for motion pic film,

and with or without perforations for driving the film.-'lhefihnshownhasperiorationsbutnotan emulsion The embodiment momma comprises a cabinet I. having a trout panel il in front of which 50 much oi amounted.- Ingeneral.afilm II, showninl 'lgrhiswoimd at its twoiends on we reels (not shown) which may be driven in anymannen-weli known in thisart loastom'aintain-thetwoendsoitheiilmshcwn. 55 in l'ig-l ata moderate'des'iee oi'tension. That the recording aparound the drlvingdrum another. 'lhisfilmmaybeafiatelongatedstrip.

semi.- as best shown in m. a,

- versed. A recording head 0 and a reproducer pick-up D are carried on the panel and are operably connected so as to move in andout, as will later be described. so that a recording stylus C and an electric reproducer needle D always lie in the same plane and the needle can'operate in the groove just after it is formed. it so desired. lit each reversal oi the him the stylus and needle are advanced the spacing oi one groove. Thus the reproducer needle adapted to operate in the groove previously formed can be connected to a.

suitable amplifier Dand head phones orto a loud speaker D to render audible the sound which has just been recorded. so that an observer can check the recording as it is done. Thus any errorgn recording can be instantly caught and, if desired,

that portion of the recording can he retaken at once. Thus thefilm i! from the firstreel (notshown) passes around idler rolls it, it, li i0 and II,

p indicated generally as 1A, thence around an idler roll i-I, then is slid aroundapreierably stationary recordlngdrumor' I other arcuate anvil indicated generally as B,

thence under idler roll i8. over the driving drum QA, around idler rolls ",7". M ind 2| wthe second reel (not shown), The above mentioned rolls are all journaled on; suitable pins'or studs carriedby the front panel ii. An electric recording head 0 having a recording stylus C and an electric reproducing pick-uplD' having ai'eproducer needle so H D ar'e so mounted adiacent the'recording drum that either the stylus or needle; or hath can be brought into engagement with a film passing around the drum. a 4 ,ThedrivingdrumAwillnowbedesci-ibedin A shalt I2 is iournaled' in suitable hearings in the cahinet -l'l andinthetrontpanel li,-anddrivenatana diustable constant speed by any suitable'aource This shalt-has keyed-so 01' power (not shown), thereon adriving drum 28 which has anouter cylindrical surface in which are mounted spaced motion bands as. and has an annualsho'ulder is. The film nengms: the friction bands.

which maybe otrubber preferably s5 55 the I 6.

aoea is slightly above the cylindrical surface of the pass through the front panel. "A shift lever 68 Q drum for greater traction, and the film when pressed laterally against the shoulder extends I slightlybeyond the outer edge of the drum opposite the shoulder.

A thin spring sheet metal disk- 26 is pressed against a hub 23 on the pulley by means of a hub 21 on a nut 21 which is screwed on the threaded outer end of the shaft 22. The hub 2l' projects slightly farther than the overhanging portion of the film so that when no pressure is' applied to the disk, it'has a tendency to stand away very slightly from the film. A finger plate 22 is journaled on the hub 21 and has along the upper edge a series of axially drilled holes 20, in each of which is placed a plunger carrying as'mall leather finger 2| which is normally pressed against the outer surface of the disk 26 by means of an inserted spring 32. Two or more similar spring-pressed fingers 22 are placed at the opposite side of the finger plate. Friction between the j finger plate 28 which, during recording vis normally stationary, and the nut 21 which rotates,

is minimized by means of suitable ball bearings 34. The finger. plate is provided at its periphery with pins 25, 36 (Figs; 1 and 2) which are adapted to engage-a stop 31 carried by the front, panel. It will be,understood from the foregoing,,that "when the shaft 22 is rotated in a counte ock-, wise direction (Fig. 1) the pin 35 will be, ought into engagement with the upper side of the stop 31, and will remain in this position until the direction of motion of the shaft 22 is reversed. During this time the large number. of fingers in the holes 20 press the spring metal plate 28' against the-overhanging edge of the film which is held at the opposite side by means of the shoulder 25, so that it is driven in the direction indicated by an arrow 11, thereby pulling the film around the recording drum, which will later i be described. At the same time the fingers in the holes 33, shown at the'bottom of thedriving drum, give the film a slight amountof push so i that it will not. have, a tendency to bind too much as it around the-stationary recording an- Above and below the 22 are located arcuate shoes ll,- which are mountedonhinge pins III, II, respectively, and which are pressed;

by. springs (not shown), thefpins being by the front panel. These shoes are norm spaced a small distance from the filmby' means of adiusting screws 29 which bear against pins. 29'' in the front panel.. These shoes prevent the film from buckling under the side-pressure of when the direction of motion of the shaft 22 is reversed 'to a clockwise direction as dicated by the arrow b, the finger plate 2l will be carried around with-the shaft 22 and its associated parts until the pin strikes the under side ofth'e stop 21, during which time the finger platewill have made almost one-half a revolution. The lar e number of fingers in the holes n'will-then be at the bottom of thedriving and will the film around the recording drum in the opn site direction, and the film will be taken from the right-hand or second jreel (not/shown) and red on to the left-hand or first re'el{-(not shown).- The recording anvil, shown in'detail in Figs; 5, "6 and '1,- is' rotatably mounted upon a stud 42 carried by. the. front panel. On this stud is mounted-aneccentric-sleeve 43] which a shouldered ledge N on which is mounted a stationary, rigid anvil member 45, which isretained against the {shoulder by means of a ring 4 which is held in place by a series of screws 41 which the recording anvil that .is secured to the sleeve 58 bymeans of screws 40, and has an adjustable stop screw 00 by means, of whichlthe position ofthe lever 4. is regulated. The anvil 0 includes athiniannularf 5 anvil element 45' which I find may advantageous- 1y be about .03" in thickness for faithful recording of high notes. The film-supporting annulus is slightlyresilient in itself and yet rigidly;

mounted to preclude vibration, and said rigid l0 mounting is preferably stationary by reason of the mechanical diiliculty of obtainingv vibrationless rigidity in a rotary mount.

.The member I! also has an outer shoulder ll". member assuu bears against the shoulder m, the anvil being of such a breadth that that! overhangs it by about -.0l"-, .A shoe "of considerable weight in the-form of an. -annulus is, Y pressed against the overh'angingedge ofthe film 2o by means of a springll which abuts'a'spllt washer l2xseated-in an annularslot "in the sleeve 42. The-outer end of the stud 42 is threaded to receive a-lock-nut whichis providedwith a handle I! for easy operation. 25

mass of the shoe III is sufficient to insure the'fllm remaining steady, under the lateral vibration-of the. recording stylus. g v At the side of the recording anvil is the recording head 0,: I stylus Of which, as will later'be described-is pressed into the-film and is "vibrated laterally by electrical imp'arted t01the head bysounds received as bya microphone (J and amplified by an amplifier C in a well known manner, and serves to form, asound groove in thefilm as'it passes beneath the stylus.- depth of the sound groove is regulated by'the lever 48 and this lever by the screw Above the recording anvil v 'up D carrying a reproducer needle D, weferably in line with the recording one function. of the recording anvilis tomove the of the eccentric 48' into and out of vccntact with the recording stylus'C'. l 'or ordinary reproduction after the recording is -done,,,the needleD' alone is in contact with sound groove "of the film while the filmis held out of contact with the stylus C'.

It will be understoodfrom thedescrlption .cf' 50 handle so as to move it.out of. contact with! the sleeve; 42, the sleeve will be freeto on the shaft "and may be turned by means the shift lever is from'the full line positionol i I Fig. 7, wherein thefilm I2 is in withthe; recording stylus tothe dotted line position where in thefilm is outoficontact'with the recording .stylus. The anvilmay be locked in either these positions by means .of the locking handle: 00 z 5| which serves t: anvil-member s! 'm'm. we thepoint ofrecordin'gunder me u recording stylus c'.-; The mm-i with'r i a series of notcheaehannelsordepressions 62 I which are equally spaced, and which.

extend entirely" d the anvil at all points itouched 'b'y thefilm; findthat for this purpose The film I! around thevthin anvil 15 the, recording so is a reproducer 'pick- 4o thatsbown 7s the stylus is operating.

Thereproducer pick-upD is carried by an arm I and described in my co-pending application Se rial No. 685,145, serves to move the recording head C outwardly a distance equal to the spacing of the depressions 45 at each actuation which is accomplished by means of reversing mechanism operated by two switches, one of which is-actuated at a time by a cutout l2, near one end of the film, and the other by a cutout l2 near the other end of the film.

This same mechanism serves to reverse the direction of rotation of the shaft 22 which then continues to propel the film in a given direction until the mechanism is again reversed and the recording head moved over to a pos tion immediately over the next recording notch or depression 45. Thus during recording the recording stylus is vibrated. laterally, as indicated by the dotted lines of Fig. 5, -and forms a V-shaped sound groove l2. Beneath this groove a ridge i2 is embossed on the opposite side of the film by the material displaced into the depression as the groove is formed.

The depression or channel may be of V-section or U-section, or variations thereof, it being important only that the capacity of the channel be such as readily to accommodate the ridge of material embossed thereinto by the recording stylus without contacting the apex of the ridge, and that the edges of the channel, slightly rounded, serve to support the film and define the overall width of the embossment. The width of the channel and of the embossed ridge will depend upon the thickness of the film to be employed and the depth and width of the cut or sound groove, the dimensions of the channel being a 1 function of the film thickness and the sound groove width. Advantageously, the depression or channel may have a width substantially equal to that of the sound groove, plus the thickness of the film employed or -a width slightly more thantwice that of the groove. This precludes interference by the channel edges with the free displacement of the film material in the extreme amplitude range of the recording stylus;

.The recording head is 'slidably mounted on a stationary guide 56 and carries an indicator mechanism 51 which is movable beneath a pointer58 to indicate'the depressionin the anvil over which '59 which is mounted on pivots Ill, and has a; pin Si in line with-thereproducer needle D, the pin engaging an arm 62 on the recording head 0. The arm 59 is supported by a screw' by means of-which the needle D is adjusted with respect to the anvil 45. Thus any movementin or out of the recorderhead causes a corresponding movement of the reproducer needle," thereby serving to keep the neetfle and stylus. always over the depression ln the anvil. Thus at any time the anvil can be shifted-by means of a the shift lever 48 from the recording position to the non-recordin position, or vice versa, the po-' sition of the anvil being fixed by the knurled nut 48' which serves as a stop. By a suitable reversing mechanism (not shown) the film can be stopped and. run backward toany given point and then fed in the same direction as that during which recording was previously done in order toplayanyportionoftherecordwhichhasbeen 'made in the film. a

The edges 'of the the surface of the anvil rolled or polished tore vduce to a minimum the noiseproduced by afilm' slidins thereover. I have found that by thus recordingsound on a strip of film as'it slides over a stationary arcuate anvil having aseries of depressions therein, as shown, a record is produced which for fidelity of tone and freedom from foreign noise of all kinds is very much superior. In'the apparatus as shown in Fig. 1,

the reproducer needle D lies in the record groove made by the, recording stylus-C when the film is traveling around the anvil 45'- in a counterclockwise direction. Thus the quality of the recording can be instantlychecked by an operator listeningto the recording as it is done. Thus any imperfections of recording can be instantly caught and that portion of the record can be repeated until it is satisfactory. A second reproducer pick-up maybe used on the opposite side of the recording stylus, so that one pick-up needle can a lways be placed in the groove just after it is formed .by the recording stylus. The

pick-up E may be supported and held in contact with the film on the anvil in any well known manner and the output-current may be amplified as in the pick-up D by means of a suitable amplifier. It will be understood that one or more such sound grooves can be formed in the untreated or smooth face of amotion picture film, and the sound thus recorded will be synchronized with the picture by means of the therein in a well known manner.

Dragging or sliding the strip of film over the opposed convex face of the anvil will insure intimate contact between the two at the point of sound recording by reason of the relative movethem between the two at such point whether or not the anvil be absolutely stationary.

I claim:

1. A film having asubstantially V-shaped support over which the film passes, means for sliding the film over the support at substantially a uniform rate, a recording tool adapted to be vibrated and to be pressed into the film to 'form a sound groove therein, the'support having a depression opposite the recording tool andparsprocket holes allel to the direction of motion of the film to .enable the tool to force the film into the depression so as to produce a ridge on the film opposite the. sound groove, and means for pre;

venting lateral motion at the point'of recordings 3. Apparatus 'forforming a sound groovetiri a face of a film comprising a rigid, stationary sup-.

port over which the film passes, means for sliding the film over the support at substantially a uniform rate, a recording tool adapted to be vibrated and to be pressed into the film to form a; sound groove therein, the support having a depression opposite the recording tool and par allel to the directioncf motion of the film to enable the tool toforce the film into the depression so as to produce a ridge on thefilm opposite the sound groove, a shoulder atone side of the support, a shoe at the other sideof the support-and a spring for the shoe inwardly so asto firmly guide thefilm, to prevent its lateral movement recording.

4. The methodof forming a. substantially-V'- shaped laterally-undulating sound groove in a at the point of the film passes over the support, thereby em- 4 strip of film comprising sliding the film over a rigid stationary support having a longitudinal deandguiding the film at therecording point to prevent its lateral movement.

5. The method of forming a sound groove in it strip of film comprising sliding the film over a rigid stationary arcuate support having a longitudinal depression formed therein, pressing a viil,0 96,118 I v bossment under theaction of the vibratory rebrating recording tool against the film over the depression'to form the sound groove therein while bossing the material of the film into the depres sion on the opposite side of the film from the adapted to be vibrated and to be pressed into sound groove, and guiding the film at the recording-point to prevent its lateral movement.

the film to form a sound groove therein as the filmis moved, the support having a groove there in oppositethe recording tool to enable "the tool to emboss the film so as to produce a ridge on ,the film opposite the sound groove. i

7. Apparatus for forming a sound groove in a face of a motion picture film comprising a rigid, j

stationary, arcuate support overwhichthefilm passes, means for sliding the film over the.sup-' port at substantially a uniform rate, and a rcording tool adapted to be vibrated and tobe pressed into'the film to form a sound groove therein, the support having a depression opposite the recording tool and parallel to the direction of motion of the film to enable the tool ,to force the film I into the groove so as to produce aridge on the film opposite the sound groove. r v

8.. Apparatus for'producing a sound record in a strip of suitable material comprising a soundactuated vibratory tool, a rigid support disposed adjacent the tooland spaced therefrom. and having formed therein a depression in register with the tool, means to draw the strip over the support between the tool and the depression whereby to form a sound groove in one face thereof and to emboss the displaced material into the depression, the width of the depression definitely defining the width of thematerial embossed into the depression, and means to hold the strip against lateral movement of the vibratory tool.

'9; Apparatus'for producing a sound record in a strip of suitable material comprising around-- actuated vibratory tool, a rigid,,arcuate support disposed adjacent the-tool and Wed therefrom, andhaving formed therein a depression in register with the tool, means to draw the strip over the support between the tool andthe depression whereby to form a sound groove in one face. thereof and to emboss the displaced material into the depression,the depression marginally defining and fixing the embossment as to widthand itself oi sufficient width and depth to permit lateral shifting therein of the medial portion of the em,-

cording tool. v

'10. Apparatus for producihg a sound recordin astrip of permanently deformable material in the form of a sound groove, said apparatus com prising arigid, arcuate support having a depres sion therein, a sou'nd-actuated vibratory tool held rigidly in register with thedepression in the supn port" and at'a substantially fixed distance therefrom, means for drawing the stripsaround the ment at the point of recording, the, width of the depression being a function of the sound groove widthand or ,the sheet thickness. I 11. Apparatus for producing asound record-in a strip of permanently deformable material in the form-of a sound: groove, said apparatus comprising a rigid, arcuate-support having a depression therein, a sound-actuated'vibratorytool hem rigidly in register with the depression in the support and at a substantially fixed distance therefrom, means-for'drawing the strip around the support at a uniform rate between the tool and depression to form a sound 8. 0ve therein,

and means for holding the strip against lateral movement at'the point of recording, the width of the depressionlbeing, more than twice the width of the sound groove; i i

I 12. The method of forming ,an undulatory" sound groove in, a strip of permanently deformable material comprising moving the strip over' support at a uniform rate between the tool and y f depression to form a soundgroove therein, and, 1 means for holding the strip against lateral movee is I sound groove inone face thereofand ,to emboss' the material into thedepression to form a ridge .on the side opposite the sound groove, the depressi'on having a width defining by contact the a face of a'strip of mm comprising a rigidly mounted arcuate support over which the film moves, means for moving the film over the supe port at substantially a uniform rate, a recording "width of the embossment but sumciently greatertool adapted to be vibrated and to be pressed into the'film to form a sound groove therein as the film is moved, the support having a de'- pression thereinopposite the recording tool; to enablethe tool to emboss the film so as to produce a ridge on the film opposite thefsound groove, and means for preventing lateral movement of the film at said int. 1 l

14. Apparatus forfforming a sound groove in a-face ,of.a strip'of film comprising a rigidly mounted stationary, arcuate support over which the film slides, means for slidingithe film over the support at substantially a uniform rate,la

recording tool adapted to be vibrated and to be pressed into the filmat any-one of a pluralityof laterally spaced points to form a pluralityQof sound grooves in, the film paralleltoeach'other v andtotheedgesofthefilmasthefilmismoved, the support having aplurality of similarly spaced depr'essionstherein opposite the recording tool to enable the tool to embossthe filmseas to 7 produces plurality oi' ridses" on the film opposite the sound grooves, and meansv for preventing the 1 lateral movement of the filmat'said point. r

i5. Apparatus-for forming a sound groove ins aooaua face of a strip of film comprising a rigidly mounted stationary, arcuate support over which the film slides, means for slidingthe film over the support at substantially a uniform rate, a recording tool adapted to be vibrated and to be pressed into the film at any one of a plurality of laterof similarly spaced depressions therein opposite the recording tool to enable the tool to emboss the film so as to produce a plurality of ridges on the film opposite the sound grooves, and means for preventing the lateral movement of the film at said point, the depressions extending around the support at all points touched by the film.

16. Apparatus for forming a sound groove in a face of a strip of film comprising a rigidly mounted stationary, arcuate support having a thickness of about .03 over which the film slides, means for sliding the film over the support at substantially a. uniform rate, a recording tool adapted to be vibrated and to be pressed into the film to form a sound groove therein as ,the film is moved, the support having a depression therein opposite the recording tool to enable the tool to emboss the film so as to produce a ridge on the film opposite the sound groove,

.and means for preventing lateral .movement of the film at said point.

17. Apparatus for forming a sound groove in a face of a strip of film comprising a rigid, stationary support over which the film slides, means for sliding the film over the support at substantially a uniform rate, a recording tool adapted to'be vibrated and to be pressed into the film to form a sound groove therein as the film is moved, the support having a depression therein opposite the recording tool to enable the tool to emboss the film :so as to produce a ridge on the film opposite the sound groove, means for preventing lateral movement of. the film at said point, a reproducer pick-up having a needle in alignment with the groove, and means for adjustably posia face of a strip of comprising a rigidly mounted stationary support overwhich the film slides, means for sliding the film over the support at substantially a uniform rate, a recording tool adapted tobe vibrated and to be pressed into the film at any one of a plurality of laterally spaced points to form a plurality of sound grooves in the film parallel to each other and to the edges of the film as the film is moved, the support having a plurality of similarly spacedv depressions therein oppositethe recording tool to enable tioning the support so as to bring the film thereon selectively into or out of engagement with the recording tool, and means for moving the re producer. needle into and out of the groove.

"18. Apparatus for forming a sound groove in a face .of a strip of film comprising a' rigid, sta- I tionary support over which the film slid'es, means -for sliding the film over the support at substantially a uniform rate, a recording tool adapted to be vibrated and tobe pressed into the film to form a plurality of sound grooves the film parallel to each other and-to the es of the film as thefiim ismoved, the support having a plurality of similarly spaced depressions therein opposite-the recording tool toenable the tool to emboss the film so as to produce a plurality of ridges on the film opposite the sound grooves.

means for preventing the lateral movement of the film at said point. a reproduc'er pick-up having a needle operably associatedwlth the re- -cording tool so into operate in the groove made by the tool, means, for positioning the support.

so"asto move'a film thereon into or out of envancing' and retracting the reproducer needle into andout of the sound groove, an element carrying both the recording tool and the pick-up, and

'm'esns for positioning the recordingtool over ga'gement with the recording tool, means forad- .being tensioned about the I former, whereby a rearward drag and hugging the tool to emboss the film so as to produce a v plurality ofridges on the film opposite the sound grooves, and means for preventing the lateral movement of the film at said point, the edges of the depression being rounded and the surface of the support polished to reduce to a minimum the noise of the film sliding thereover.

20. A methcd'of sound recording including the steps of inducing. relative surface movement be-- tween, a record strip of permanently deformable material and an arcuate support having a chanj nei in its arcuate face, the strip being tensioned' about the arcuate face of the support, whereby a dragand hugging contact of -;the strip with the support.is maintained, and bringing a vibrato'ry sound-actuated recording stylus. into pressure engagement with the strip in line with the channel to emboss stylus into the channel.

21. A method of sound recording including the steps of inducing relative'surface movement between a record strip of permanentlyfleformable material and an arcuate support having a plurality of substantially parallel channels in its opposed-face, the strip being tensioned about the arcuate face of the support, whereby a drag and hug ing contact of the strip with the support is maintained, bringing a vibratory sound-actuated recording stylus into pressure engagement with the strip in line with one of the channels to emboss material displaced bythe stylusinto said channel, and bodily shifting the stylus into line with an adjacent channel to produce a second sound record groove adjacent and parallel to the first. I v

22. Apparatus for recording sound including an arcuate support having in the face thereof a channel, a sound-actuated vibratory recording stylus mounted above and in line with the channel, means to slide a strip of permanentlydeformable material over and in contact with the channeled face of the support beneath the stylus, the coacting faces of the support and the strip having relative surface movement and the latter curved face of the action is. imparted to'the'strip, means-to impart by the stylus pressure upon the strip concurrently with the sound-actuated vibration of the stylus whereby to emboss the material of the strip into the channel to produce an undulatory sound groove in the upper face of the strip and the cor-' 'w nding ridge upon the lower face.

23. Apparatus for recording sound including an arcuate suppo t havingin 'the face thereof a plurality of substantially parallel channels, a sound-actuated vibratory recording stylus mounted aboveand.in line with one of the channels, means to slide a strip of permanently deformable material over and in contact with the channeled face of thesupporhbeneath the stylus, thecoacting faces of the support and the strip having relative surface movement and the latter being tensioned about the curved face of material displaced by the the former, whereby a rearward drag and hugglng action ls imparted to the strip, means to impart by the stylus 'pressure upon the strip concurrently-with the sound-actuated vibration of'the' stylus whereby to embosa the material of the strip into the channel to produce an'un- 3,090,118 V dulatory sound groove lnthe upper face otthe v strip and the eorrespondlna rldk umnthe lower face, and means to bodily lhlftithe reoonllnl stylus laterally or the support'and strip tuba-In: the stylus into line with a dlflerent channel.

JOHNNY. m

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