US1719339A - Talking-machine record - Google Patents

Description

July 2, 1929- N. REDDIE E1 AL TALKING HACHINE RECORD Filed Nov. 18, 1925 Patented July 2, 1929.

UNITED STATES v 1,719,339 PATENT OFFICE.

LOVELIa NEWTON REDDIE OF LONDON, ANI) BRENCHLEY ERNEST GEORGE MITTELL, 0F IVER, ENGLAND, ASSIGNORS TO VICTOR TALKING MACHINE COMPANY, OF CAMDEN, NEW JERSEY, A CORPORATION OF NEW JERSEY.

TALKTNG MAGHINE RECORD.

Application filed November 18, 1925, Serial No. 69,847, and in Great Britain December 24, 1924.

This invention relates to improvements in and relating to talking machine records.

It is known that a record upon a wax cylinder gives in some respects a more faithful reproduction of the recorded sounds than a record out upon a disc, and the proposal has been made to record sounds upon a'wax cylinder, by the usual or any known method,

and to transfer the record so obtained from the c linder to a disc. It has been proposedto e eat this transfer operation by mechanical means such as a lever, one end of which traces in the sound line out on the wax cylinder whilst the other end of the lever is furnished with a cutting tool whereby a record is cut in a wax disc. From the wax disc a matrix is made in the usual or any suitable way and from the matrix a number of recordscan be pressed.

In this transferring operationit has been proposed not only to transfer an up and down out from a cylinder and to obtain an up and down out on a disc, but it has been proposed also to convert the up and down out on the cylinder into a lateral cut of uniform depth on the disc.

There are certain difiiculties in performing this mechanical transfering operation. It is desirable that the tracing point and the recording tool should both rest quite lightly on the surfaces with which they respectlvely cooperate and it is diflicult to arrange a cylinder and a disc sufficiently closeto one another to enable the transferring mechanism to be sufliciently light and at the same time sufficiently rigid. The movements of the tracing point and cutting point are necessarily very rapid, where sounds of high frequency are being transferred, and this is ill true even thou h in the transferring operation the cylinder and disc are rotated at much lower speeds than those at which the cylinder was first recorded and the disc record will be played. If the transferring mechanism possesses any considerable mass,

4 it will be understood that these rapid movements result in the tracing point and recording tool respectively performing movements which do not accurately correspond to the sound record cut onthe wax cylinder. If in the transferring operation an up and down out on the cylinder has to be converted into a lateral'cut on the disc the difficulties as referred to above are increased.

is of the well One of the objects of the present inventlon is to remove these difficulties in the operation of transferring from one recorded surface to another.

According to the present invention, in the transformation of a sound record of one knid into a sound record of a different kind, the sound after being recorded is converted into electrical oscillations which are adapted to operate a recording device.

Further, according to.the present invention' a sound record of any kind may be transferred to a sound record cut in a solid body, that is to say.a record adapted to be reproduced. by mechanical means, by converting the first sound record into electrical oscillations which are caused tocut the rec- 0rd in the solid body.

Means may mg the electrical oscillations either to-accentuate or to diminish certain ranges of frequency or to alter the amplitude of the whole, and to permit'of the adjustment of these controlling means a reproducer or loud speaker may be connected in such a manner as to reproduce the electrical oscillations in the form in which they are being recorded.

One method of carrying out the invention will now be described, by way of example, with reference to the accompanying drawmg in which is shown diagrammatically a method of transferring a sound record, of either up and down or lateral cut type, from a cylinder to form'a record, of either up and down or lateral cut type, upon a disc.

A reproducing stylus a traces lightly in and is oscillated by the sound line upon the rotating cylinder 6 and thereby generates feeble oscillating currents in the primary 0 of the input transformer d. The reproducing device e may be of any known or suitable form. The oscillating electromotive forces set up in the secondary f of the transformer d are impressed upon the grid circuit of a thermionic valve which is the first valve of an amplifier which may comprise any desired number, of valves although, in the present example, three are shown. .The intervalve coupliiiggillustratecl known resistance-capacity type. The oscillating currentsfrom the last amplifying valve b are passed'through the primary 6 of an output transformer j and currents generated in the secondary k of this also be provided for modifytransformer pass to the recording device Z,

lines as the reproducing device 6. The

stylus m of the recording device 1 cuts a record upon the rotating disc at. i

Control of the volume and quality of the sound transmitted is obtained by the following means: The primary 0 and the secondary f of the input transformer (13 are made so that their inductances are variable either by means of suitable tappings or otherwise and a variable condenser 0 is connected in parallel with the secondary k of the output transformer j. Adjustment of each of these three controlling means will alter both the amplitude and the wave form of the electrical oscillations but in the main it may be said that adjustment of the primary c and of the condenser 0 serves to control the wave form of the oscillations whilst adjustment of the secondary f mainly affects the amplitude of the oscillations since the currents flowing in the grid circuit are only those due to inter-electrode capacity and are consequently very small compared with the currents flowing in the circuits of the reproducing device 6 and of the recording device Z. In order that the operator may be able to listen to the sounds in the form in which they are being recorded and so make any necessary adjustments during the process of transference, a loud speaker p is provided and is connected across a small portion of a resistance 9 which is shunted across the secondary k of the output transformer j, the currents required to operate the recording device I being in general much greater than those required to operate the loud speaker satisfactorily.

The record upon the cylinder may be made b the direct action of sound waves upon a diaphragm connected with the recording tool or the sound waves may be allowed to strike a microphone, or equivalent means for converting sound oscillations into electrical oscillations, and to produce electrical oscillations in a circuit containing a suitable thermionic amplifier, the amplified oscillations being used to operate an electrical recording device, or the record on the'cylinder ma be produced in any other known or suitab e manner.

The tracin point and also the recording tool used in t e transferring process may be made very light and the transferring may take place at a speed considerably lower than that at which the record was originally Y made so that the movement of the oscillating parts can be made to correspond very accurately with the sound record cut on the cylinder. In order to still further reduce the possibilities of distortion due to the inertia of moving parts a record may first be made by anyknown process, such as that employing a cathode ray oscillograph device, in

which all oscillating parts are substantially inertia-free and this record may then be transferred by the method according to the present invention, at a reduced speed, to a record which is in the most convenient form for reproduction. In the case of the production of a wax record, the speed may be adjusted so thatsubstantially no distortion is introduced owing to the mass of the oscillating stylus and the most suitable cutting speed for the wax may also be taken into consideration.

The present invention, therefore, is not confined to the operating of transferring a sound record from a wax cylinder to a disc. Sound records are well known in the form offilms, for example, on which a photographic record is made, a beam of light which falls on the film being moved, or its intensity being varied, by and in accordance with sound waves, or the photographic sound record may be produced by a cathode ray oscillograph device. From these photographic records, sound has been reproduced in a variety of ways, as for example b passing light through them, whilst in motion, on to a light-sensitive cell, from which a variable current is derived, and this current, after amplification by means of thermionic valves for example, is used to actuate a loud speaking telephone; or the photographic film may be used to provide a variable capacity, to vary an electric current in accordance with the sound waves recorded.

Sound records are also known which are recorded by effecting the variable magnetization of metal bodies such as wire, metal ribbons, or metal discs, and from these records variable electric currents are derived by suitable means which, after amplification by thermionic valves, actuate a loud speaking telephone.

Sound records in the form of films, ribbons or wire are not easily handled, and the apparatus for reproducing therefrom is of a delicate and highly technical nature and 110% 1of a kind suitable for use by the general pu 1c.

The present invention may be applied to the purpose of obtaining, from sound records of the above mentioned type, or frpm whatever type of record constitutes an" accurate and faithful record of the sounds which-it is i desired to reproduce, electrical currents or,

current impulses' which after amplification by thermionic valves, are used to operate a recording tool to cut a record in a body of a. convenient form for handling, such as a cylinder or disc, which gor duplicates of which) can be reproduce with a talking machine, that is to say, can be reproduced by mechanical means.

A further application of the present invention is in the preparation of a new wax blank from an existing talking machine matria or record. There are matrices which have been in existence for several years and possess considerable historical and musical value, but may have some imperfections due possibly to the less perfect recording method in use when they Were made. A suitably formed tracing point can be made to track on these matrices, or on a record made therefrom, the currents thereby produed are am,- plified as above described and anew Wax blank is cut. During the transferring process the amplification of any imperfect passages can be modified, as for example by reducing the amplification of a passage that is too loud, by increasing momentarily the resistance in some part of the circuit, or the quality of certain passages can be altered (e. g. to bring out the overtones) by using a variable condenser in series in the circuit to or from the amplifier, the overtones being emphasized by reducing the capacity.

lFVe claim:

1. The method of transforming a mechanically recorded sound record into an electromechanically recorded sound record which consists in employing the sound record to be transformed for producing mechanical vibrations, converting said vibrations into feeble oscillating currents in an electrical circuit, audibly reproducing said currents, variably controlling both the amplitude and the Wave form of said currents according to the audible reproduction to render the same more pleasing, transferring the currents so a controlled into mechanical vibrations, and

recording said mechanical vibrations on the other record ltatent I la. lfillhdd h lt la herehr eertilied that error anaem a in ahove nurnhererl patent requiring retraction as follows: 2, atrihe out the word "by"; same page, line 61, claim caarrrrea'ra or GORREGTION WWN REDDIE ET AL.

2. The method of transferring sound mechanically recorded on by a sound record onto a recording surface which consists in moving said sound record at a speed considerably lower than that at which said sound record Was originally made, employing said slowly moving record for producing feeble oscillating currents in an electric circuit, audibly reproducing said currents, variably controlling both the amplitude and wave form of said currents according to the audi ble reproduction to render the same more pleasing, and transferring the currents so controlled onto said recording surface.

3. The method of transferring a sound record from a cylinder onto a disk which consists in moving said cylinder at a speed considerably lower than that at which said sound record Was originally made, employing the sound record to be transferred for producing mechanical vibrations, converting said vibrations into feeble oscillating currents in an electrical circuit, audibly reproducing said currents variably controlling both the amplitude and Wave form of said currents according to the audible reproduction to render the same more pleasing, trans ferring the currents so controlled into me-v chanical vibrations and recording said mechanical vibrations on said disk.

In testimony whereof, We have signed our names to this specification at London, England, this third and fourth days of November, 1925, respectively.

LOVELL NEWTON REDDIE. BRKENCHLEY ERNEST GEORGE MITTELL.

Granted my 2, 1929, to

the printed specification of the Page 3, line 39, claim 3, after the word "currents" iuaert a comma; and that the said Letters Patent should be read with corrections thereia that the same we in. the Patent lhllice,

y conform to the record of the case 7 hianerl hurl aealerl this llith ray of hotelier, A, l) I M, J. Moore, hating Commissioner of Patents.

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