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PHONOGRAPH (Gr. c&JP , sound, ypacbew...

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Originally appearing in Volume V21, Page 471 of the 1911 Encyclopedia Britannica.
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PHONOGRAPH (Gr. c&JP , See also:sound, ypacbew, to write) , an See also:instrument for imprinting the vibrations of sound on a moving See also:surface of tinfoil or See also:wax in such a See also:form that the See also:original sounds can be faithfully reproduced by suitable mechanism. Many attempts had been made by earlier experimenters to obtain tracings of the vibrations of bodies emitting sound, such as tuning-forks, membranes, and See also:glass or metallic disks. In 1807 See also:Thomas See also:Young (Lectures, i. 191) described a method of recording the vibrations of a tuning-See also:fork on the surface of a See also:drum; his method was fully carried out by Wilhelm Wertheim in 1842 (Recherches sur l'elasticite, ii" mem.). Recording the vibrations of a membrane was first accomplished by See also:Leon See also:Scott in 1857 by the invention of the " phonautograph," which may be regarded as the precursor of the phonograph (Comptes rendus, 53, p. 1o8). This instrument consisted of a thin membrane to which a delicate See also:lever was attached. The membrane was stretched over the narrow end of an irregularly-shaped See also:funnel or drum, while the end of the lever or marker was brought against the surface of a See also:cylinder covered with See also:paper on which See also:soot had been deposited from a See also:flame of See also:turpentine or camphor. The cylinder was fixed on a See also:fine See also:screw moving horizontally when the cylinder was rotated. The marker thus described a See also:spiral See also:line on the blackened surface. When sounds were transmitted to the membrane and the cylinder was rotated the oscillations of the marker were recorded. Thus tracings of vibrations were obtained.

This instrument was much improved by Karl See also:

Rudolph See also:Konig, of See also:Paris, who also made with it many valuable observations. (See Nature, Dec. 26, 1901, p. 184). The mechanism of the recording lever or marker was improved by See also:William See also:Henry See also:Barlow, in 1874, in an instrument called by him the " logogriph " (Trans. See also:Roy. See also:Soc., 1874). The next step was Konig's invention of manometric flames by which the oscillations of a thin membrane under sound-pressures acted on a small See also:reservoir of See also:gas connected with a flame, and the oscillations were viewed in a rotating rectangular See also:mirror, according to a method devised by See also:Charles See also:Wheatstone. Thus flame-pictures of the vibrations of sound were obtained (Pogg. See also:Ann., 1864, cxxii. 242, 66o; see also Quelques experiences d'acoustique, Paris, 1882). See also:Clarence See also:Blake in 1876 employed the drum-See also:head of the human See also:ear as a logograph, and thus obtained tracings similar to those made by artificial membranes and disks (Archie.

See also:

fur Ophthalmol., 1876, v. I.). In the same See also:year Sigmund Theodor See also:Stein photographed the vibrations of tuning-forks, See also:violin strings, &c. (Pogg. Ann., 1876, p. 142). Thus from Thomas Young downwards successful efforts had been made to See also:record graphically on moving surfaces the vibrations of sounds, but the sounds so recorded could not be reproduced. This was accomplished by T. A. See also:Edison in 1876, the first patent being dated See also:January 1877. In the first phonograph a spiral groove was cut an a See also:brass drum fixed on a See also:horizontal screw, so that when the drum was rotated it moved from right to See also:left, as in the phonautograph. The See also:recorder consisted of a membrane of See also:parchment or See also:gold-beater's skin stretched over the end of a See also:short brass cylinder about 2 in. in See also:diameter.

In the centre of the membrane there was a stout See also:

steel See also:needle having a See also:chisel-shaped edge, and a stiff See also:bit of steel See also:spring was soldered to the needle near its point, while the other end of the spring was clamped to the edge of the brass cylinder over which the membrane was stretched. The recorder was then so placed beside the large cylinder that the See also:sharp edge of the needle ran in the See also:middle of the spiral groove when the cylinder was rotated. The cylinder was covered with a See also:sheet of soft tinfoil. During rotation of the cylinder, and while the membrane was not vibrating, the sharp edge of the marker indented the tinfoil into the spiral groove; and when the membrane was caused to vibrate by sounds being thrown into the short cylinder by a funnel-shaped opening, the See also:variations df pressure corresponding to each vibration caused the marker to make indentations on the tinfoil in the bottom of the groove. These indentations corresponded to the sound-waves. To reproduce the sounds the recorder was See also:drawn away from the cylinder, and the cylinder was rotated backwards until the recorder was brought to the point at which it started. The cylinder was then rotated forwards so that the point of the recorder ran over the elevations and depressions in the bottom of the groove. These elevations and depressions, corresponding to the variations of pressure of each sound-See also:wave, acted backwards on the membrane through the See also:medium of the marker. The membrane was thus caused to move in the same way as it did when it was made to vibrate by the sound-waves falling upon it, and consequently movements of the same See also:general See also:character but of smaller See also:amplitude were produced, and these reproduced sound-waves. Consequently the sound first given to the phonograph was reproduced with considerable accuracy. In 1878 Fleeming Jenkin and J. A.

See also:

Ewing amplified the tracings made on this instrument by the sounds of vowels, and submitted the curves so obtained to See also:harmonic See also:analysis. (Trans. Roy. Soc. Edin. See also:xxviii. 745). The marks on the tinfoil were also examined by P. F. F. Griitzner, See also:Mayer, See also:Graham See also:Bell, A. M. Preece, and See also:Lahr (see The See also:Telephone, the Microphone, and the Phonograph, by See also:count du Moncel, See also:London, 1884; also The Speaking Telephone and Talking Phonograph, by G.

B. See also:

Prescott, New See also:York, 1878). The tinfoil phonograph, however, was an imperfect instrument, both as regards the medium on which the imprints were taken (tinfoil) and the general mechanism of the instrument. Many improvements were attempted. From 1877 to 1888 Edison was engaged in working out the details of the wax-cylinder phonograph. In 1885 A. G. Bell and S. Tainter patented the " grapophone," and in 1887, Emile Berliner, a See also:German domiciled in See also:America, patented the " See also:gramophone," wherein the cylinder was coated with lampblack, and the See also:friction between it and the stylus was made See also:uniform for all vibrations. Incidentally it may be mentioned that Charles See also:Cross deposited in 1877 a sealed packet with the Academie See also:des Sciences, Paris, containing a See also:suggestion for reproducing sound from a Scott phonautograph record. The improvements made by Edison consisted chiefly (i) in substituting for tinfoil cylinders or disks made of a waxy substance on which permanent records are taken; (2) in substituting a thin glass See also:plate for the parchment membrane; (3) in improving the See also:mechanical See also:action of the marker; and (4) in See also:driving the drum carrying the wax cylinder at a uniform and rapid See also:speed by an electric motor placed below the instrument. In the first See also:place, permanent records can be taken on the wax, which is composed of stearin and See also:paraffin.

This material is brittle, but it readily takes the imprints made by the marker, which is now a tiny bit of See also:

sapphire. The marker, when used for recording, is shod with a chisel-shaped edge of sapphire; but the sapphire is rounded when the marker is used for reproducing the sound. The marker also, instead of being a stiff needle coming from the centre of the membrane or glass plate, is now a lever, weighted so as to keep it in contact with the surface of the wax. A single vibration of a pure See also:tone consists of an increase of pressure followed by a diminution of pressure. When the disk of glass is submitted to an increase of pressure the action of the lever is such that, while the wax cylinder is rotating, the point of the marker is angled downwards, and this cuts deeply into the wax; and when there is diminution of pressure the point is angled upwards, so as to See also:act less deeply. In reproducing the sound, the See also:blunt end of the marker runs over all the elevations and depressions in the bottom of the groove cut on the wax cylinder. There is thus increased pressure transmitted upwards to the glass disk when the point runs over an See also:elevation, and less pressure when the point runs over a depression on the wax cylinder. The glass disk is thus, as it were, pulled inwards and thrust outwards with each vibration, but these pulls and thrusts follow each other so rapidly that the ear takes no See also:cognizance of the difference of phase of the vibrations of the glass plate in imprinting and in reproducing. The variations of pressure are communicated to the glass plate, and these, by the medium of the See also:air, are transmitted to the drum-head of the ear, and the sound is reproduced with remarkable fidelity. It is necessary for accurate See also:reproduction that the point of the marker be in the centre of the groove. In the older phonographs this required accurate See also:adjustment by a fine screw, but in newer forms a certain amount of lateral oscillation is allowed to the marker, by which it slips automatically into the groove. Two other improvements have been effected in the construction of the instrument.

A powerful triple-spring motor has been substituted for the electric motor, and the circumference of the wax cylinder has been increased from 68 in. to 15 in., whilst the disk is 12 in. in diameter. The cylinders make about two revolutions per second, so that with the smaller cylinder the point of the marker runs over nearly 14 in. in one second, while with the larger it runs over about 30 in. The marks corresponding to the individual vibrations of tones of high See also:

pitch are there-fore less likely to be crowded together with the larger cylinder, and these higher tones in particular are more accurately reproduced. In a form of instrument called the zoo-See also:thread See also:machine See also:motion of the drum bearing the cylinder was taken off a screw the thread of which was 5o to the See also:inch, and by a See also:system of gearing the grooves on the cylinder were 200 to the inch, or aka of an inch apart. It was somewhat difficult to keep the marker in the grooves when they were so See also:close together; and the See also:movement is now taken directly ofa screw the thread of which is too to the inch, so that the grooves on the cylinder are Th of an inch apart. Thus with the large cylinder a spiral groove of over 300 yds. may be described by the recorder. and with a speed of about two revolutions per second this distance is covered by the marker in about six minutes. By diminishing the speed of revolution, which can be easily done, the See also:time may be considerably lengthened. In the plate machine the disk is fixed to a table which is rotated at a fixed speed of about 76 revolutions a See also:minute. The speed of the lateral movement of tlfe table is also uniform, and by a See also:regular progression brings the wax See also:blank under the sound-See also:box to the sapphire cutting point, which detaches a fine unbroken thread of wax as it cuts into the surface of the blank to a See also:depth of 31-to 4-thousandths of an inch, beginning at about See also:half an inch from the circumference and continuing the spiral groove to within a couple of inches of the centre, according to the length of the See also:music to be recorded. The essential difference between the disk and cylinder machine is that in the former the waves are recorded by horizontal motion over the disk, while in the latter the waves are recorded as indentations. The following is the modus operandi of making a record. The See also:person making the record sings or plays in front of a See also:horn or funnel used for the purpose of focusing the sound-waves upcn the See also:diaphragm.

The artist and the funnel are on one See also:

side of a See also:screen and the recording apparatus in See also:charge of an operator on the other. The arrangement of the various See also:instruments in the recording See also:room at proper relative distances from the horn is of the utmost importance in See also:order to preserve the See also:balance of tone. At about 4 ft. from the horn are grouped the violins and the See also:wood See also:wind (flutes, oboes and clarinets) ; behind the brass wind (horns, trumpets, trombones and tubers), and right at the back the violoncellos and See also:double basses and the See also:kettle-drums and other instruments of percussion which may be required. On the other side of the screen is the sound-box and the recording cylinder or disk. Cylinder records are duplicated by taking a See also:plaster See also:cast, See also:electroplating, and then using it as a See also:matrix. The disk record admits of similar treatment. After dusting with See also:graphite it is electroplated to about '9 mm. thick. This forms the permanent or See also:master record, from which the working negatives are made by taking wax impresses of it and obtaining See also:copper electros in turn from them. The matrix is then See also:nickel-plated and polished and is ready for use in pressing out the commercial records by means of an See also:hydraulic See also:press, the material used being a tough and elastic substance containing shellac and other compounds such as wood See also:charcoal, See also:barium sulphate, earthy colouring matters and See also:cotton See also:flock. There is still a defect to be overcome in the gramophone, and that is the hissing of the needle produced by friction both during recording and intensified in reproduction. In cne See also:device for remedying this the stylus acts like a stylographic See also:pen, depositing on a polished surface a fine stream of some liquid which solidifies and hardens very rapidly, forming a sinuous See also:ridge instead of a groove in a wax blank. A negative is taken of the record and the matrix is made from it in the usual way.

jilllIIIIIIIIIIIMEMi-ifdiIlCUjpjVU101>n jlVIII ~(C If'See also:

ill~~ The auxeto-gramophone or auxetophone, patented by Short in 1898 and improved by the Hon. C. A. See also:Parsons, is similar in See also:scope to the gramophone but attains its results in a different manner. In the Parsons-Short sound-box there is no diaphragm, but a See also:column of compressed air is controlled by a delicately adjusted grid-See also:valve consisting of a See also:metal See also:comb rigidly connected to the stylus See also:bar, so that as the needle moves the metal comb moves with it, following the lines of vibration fixed on the record and opening or closing the slots in the valve seat. The column of compressed air to which the valve gives See also:access thus receives See also:series of minute pulsations identical with those which originally produced the sounds recorded. In connexion with the sound-box is the apparatus for supplying compressed air, consisting of a See also:sixth-See also:horse See also:power electric motor dnving the See also:compressor, an oil See also:filter, a reservoir and a dust See also:collector to keep the air absolutely See also:free from See also:foreign substances likely to interfere with the action of the valve. The See also:practical possibilities of the gramophone are being realized in many countries. Matrices of the records of well-known artists have been deposited at the See also:British Museum and at the See also:Grand See also:Opera in Paris. See also:Austria established a public phonogram record See also:office in 1903, in which are collected folk-songs and records of all kinds for enriching the See also:department of ethnography. The same See also:idea is being carried out in See also:Germany A O by private See also:societies and by royal museums. In See also:Hungary records of the various dialects have been secured.

The possibilities of the gramophone as a teacher are far-reaching, not only in the domain of music but in learning See also:

languages, &c. To understand how the phonograph records and reproduces musical tones, it is necessary to remember (I) that pitch or frequency depends on the number of vibrations executed by the vibrating See also:body in a given See also:period of time, or on the duration of each vibration; (2) that intensity or loudness depends on the amplitude of the movement of the vibrating body; and (3) that quality, timbre or clang, first, depends on the form of the individual vibrations, or rather on the power the ear possesses of appreciating a See also:simple pendular vibration producing a pure tone, or of decomposing more or less completely a See also:compound vibration into the simple pendular vibrations of which it is composed. If we apply this to the record of the phonograph, we find that, given a See also:constant and sufficiently rapid velocity of the record, a See also:note or tone of a certain pitch will be heard when the marker runs over a number of elevations and depressions corresponding to the frequency of that note. Thus if the note was produced by 200 vibrations per second, and suppose that it lasted in the music for of a second, 20 marks, each made in s of a second, would be imprinted on the wax. Consequently, in reproduction, the marker would run over the 20 marks in rof a second, and a tone of that frequency would be reproduced.4.69 The loudness would correspond to the depth of each individual See also:mark on the cylinder or the width on the disk. The greater the depth of a series of successive marks produced by a loud tone, the greater, in reproduction, would be the amplitude of the excursions of the glass disk and the louder would be the tone reproduced. Lastly, the form of the marks corresponding to individual vibrations would determine the quality of the tone or note reproduced, by which we can distinguish the tone of one instrument from another, or the sensation produced by a tone of pure and simple quality, like that from a well-bowed tuning-fork or an open See also:organ See also:pipe, and that given by a See also:trumpet or an See also:orchestra, in which the sounds of many instruments are blended together. When the phonograph records the sound of an orchestra it does not record the tones of each instrument, but it imprints the form of impression corresponding to the very complex sound-wave formed by all the instruments combined. This particular form, infinitely varied, will reproduce backwards, as has been explained, by acting on the glass plate, the particular form of sound-wave corresponding to the sound of the orchestra. Numerous instruments blend their tones to make one wave-form, and when one instrument predominates, or if a human See also:voice is singing to the See also:accompaniment of the orchestra, another form of sound-wave, or rather a complex series of sound waves, is imprinted. When reproduced, the wave-forms again exist in the air as very complex variations of pressure; these act on the drum-head of the human ear, there is transmission to the See also:brain, and there an analysis of the complex sensation takes place, and we distinguish the See also:trombone from the See also:oboe, or the human voice from the violin See also:obbligato. Many efforts have been made to obtain graphic tracings of wave-forms imprinted on the wax phonograph records.

Thus J. G. M'Kendrick took 13 (1) celloidin casts of the FIG. 3. surface, and (2) micro- photographs of a small portion of the cylinder (Journ. of Anat. and Phys., See also:

July 1895). He also devised a phonograph recorder by which the curves were much amplified (Trans. Roy. Soc. Edin., vol. xxxviii.; Proc. Roy. Soc. Edin., 1896-1897, Opening Address; Sound and Speech Waves as revealed by the Phonograph, London, 1897; and Schafer's Physiol., vol. ii., " Vocal Sounds," p.

1229). As already mentioned, so See also:

long ago as 1878 Fleeming Jenkin and Ewing had examined the marks on the tinfoil phonograph. See also:Professor Ludimar See also:Hermann, of See also:Konigsberg, took up the subject about 189o, using the wax-cylinder phonograph. He obtained photographs of the curves on the wax cylinder, a See also:beam of See also:light reflected from a small mirror attached to the vibrating disk of the phonograph being allowed to fall on a sensitive plate while the phonograph was slowly travelling. (For references to Hermann's important papers, see Schafer's See also:Physiology, ii. 1222.) Boeke, of See also:Alkmaar, has devised an ingenious and accurate method of obtaining curves from the wax cylinder. He measured by means of a See also:microscope the transverse diameter of the impressions on the surface of the cylinder, on different (generally equidistant) parts of the period, and he infers 3 2 e 165 VD. 4 264 VD C 132 V.D. 1,91 VD. 6 7 9 10 A11 12 /327V.D.169,4VD2012 2 25, 6VD 16 15 from these measurements the depth of the impressions on the same spot, or, in other words, he derives from these measurements the See also:curve of the vibrations of the tone which produced the impression A 0 (Archiv. f. d. ges. Physiol. See also:Bonn, Bd.

1, S. 297; also Proc. Roy. Soc. Edin., 1898). From a communication to the Dutch Otorhinolaryngological Society Dr Boeke has permitted the author to select the accompanying illustrations, which will give the reader a See also:

fair conception of the nature of the marks on the wax cylinder produced by various tones. Fig. 2 shows portions of the curves obtained by Hermann, and enlarged by Boeke one and a half times. The See also:numbers 1 to 4 refer to periods of the vowel A (as in " hard "), sung by Hermann on the notes c e g c'. Numbers 5 to 8 show the curves of the vowel o (as in " go ") sung to the same notes. The number of vibrations is also noted. Boeke measured the marks for the same vowels by his method, from the same cylinder, and constructing the curves, found the relative lengths to be the same.

In fig. 3 we see the indentations produced by the same vowels, sung by Hermann on the notes c e g c', on the same phonograph cylinder, but delineated by Boeke after his method. The curves are also shown in linear See also:

fashion beside each See also:group of indentations. From these measure-ments the curves were calculated and reproduced, as in fig. 4. Thus the curves of the same vowel sounds on the same cylinder are shown by two methods, that of Hermann and that of Boeke. In fig. 5 we see the indentations on the vowel a, sung by Dr Boeke, aged 55, on the notes c d e f gab c', and near the frequencies of 128, 144, 16o, 170•6, 192, 213.3, 240 and 256. The numbers 33 to 40 show the marks produced by the same vowel, sung by his son, aged 13. It will be seen that the boy sang the notes exactly an See also:octave higher. Fig. 6 shows the marks produced by some musical e's 44 42 ,43 244 45 46 4 67 545e I 4 4.5S 1Y 4 sounds.

Each shows on the right-See also:

hand side the curve deduced from the marks, and under it a graphical See also:representation of the results of its harmonic analysis after the theorem of See also:Fourier, in which the ordinates represent the amplitude of the subsequent harmonic constituents. No. 41 is the period of the sound of a pitch-pipe giving a' (425 double vibrations per second), No. 42 the period of a Dutch pitch-pipe, also See also:sounding a' (424.64 double vibrations per second). No. 43 is a record of the period of a sound produced by blowing between two strips of indiarubber to imitate the vocal cords, with a frequency of 453 double vibrations per second. No. 44 is that of a telephone pipe used by Hermann (503 double vibra- tions per second). Nos. 45 and 46 show the marks of a See also:cornet sounding the notes a oft 400 double vibrations per second, and e of 300 double vibrations per second. In fig. 7 are shown a number of vowel curves for the vowels o, oE, A, E and i.

Each curve has on the right-hand side a graphical representation of its harmonic analysis. The curves are in five See also:

vertical columns, having on the d e f g m be. c' c d e' f 191 t' b' c~ 427 W. 453 V.D.475V.D. `t4 ) 3 f7 /8 19 27 C 21 132 VD. e 22 165 VD. 9 23 188 VD. Cl 2¢ 26¢ V.D. 0 A Da/AA ?O D (and u, JJ A0CLlC4 5 V J M al 52j, 49 oe 2J u J 7 ` 40 45 _ German v v ` JJ El ILdIL o v 8 la„dll I Dutch D u,uao: pp 7.9~Mr..w.,.~_ ~ 69 N 17 AI. 6711/~M^n..,. \ ..."°•"fill 536dti^^^ S 6 a g ef~n~-ti.._ I sic,• p Il...nl~. .1k. V N NiN ._ `7 111 7 Js See also:French .n..AL..

.,,itllll i left-hand side of each drawings, by Boeke's method, of two periods of the marks of the vowel. The marks are shown for the Dutch, German, See also:

English and French languages. The sounds of the vowels are o, like o in " go " oe, like oo in " too "; u, like the German it in " Fiihrer " a, like a in " hard ' e, like a in " take " ij, not in English words, but somewhat like e in " bell "; and i, like ee in " See also:beer." The first See also:section contains only Dutch vowel sounds, either sung or spoken by Boeke or members of his See also:family. The second section contains curves from the voice of Professor Hermann, the third from the voice of the author from a cylinder sent by him to Dr Boeke, and the See also:fourth from the voice of See also:Mons. H. Marichelle, professeur de l'Institut des Sourds-Muets, also forwarded by him to Dr Boeke. Thus curves and marks of the same vowel are shown from the voices of men of four nationalities. On the construction of the gramophone, see L. N. Reddie, Journ. Soc. Arts (1908).

End of Article: PHONOGRAPH (Gr. c&JP , sound, ypacbew, to write)

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