US3023659A - Transposition apparatus for electrical musical instrument - Google Patents

Description

March 6, 1962 H. E. w. BODE 3,023,659 TRANSPOSITIQN APPARATUS FOR ELECTRICAL MUSICAL INSTRUMENT Filed July 11, 1960 United States Patent G 3,023,659 TRANSPOSHION APPARATUS FOR ELECTRICAL MUSIAL INSTRUMENT Harald E. W. Bode, Corinth, Miss, assignor to The gg rlitzer Company, Chicago, 111., a corporation of Filed July 11, 1960, Ser. No. 41,960 5 Claims. (Cl. 84-445) This invention relates to electronic musical instruments and more particularly to novel apparatus especially adapted for use with keyboard instruments such as electronic organs which enables the player of the instrument to transpose music to different key signatures without necessitating an involved mental process for each note so that each digital (key), actuated in normal manner, may produce a musical sound from a tone generator that is selectively displaced a desired and similar amount from the note indicated by the musical score, for example. Musical compositions are usually written in a particular key signature but as it is often desired to play the instrument in conjunction with other instruments or to accompany people in singing, for example, the key indicated on the score may not be suitable in particular instances and therefore a transposition either to a higher key signature or to a lower key signature is necessary. While transposition from one octave to the next, either higher or lower, is comparatively easy, such octave transpositions are of too large a magnitude in most if not all cases and it is necessary to operate digitals (including adjustment for sharps and flats) that are displaced a uniform amount from the digitals indicated on the score. This is often an arduous task for even the professional to perform easily and accurately and often is impossible for the amateur to play so that the expected and desired satisfaction is obtained from the performance.

Accordingly, it is an object of this invention to provide a simple key or pitch changing apparatus capable of easy manipulation so that even a layman may play music in any key signature by limiting himself to one and only one key (for instance the key of C).

Another object of the invention is to provide apparatus which enables a provision of a more versatile and improved electronic musical instrument.

A further object of the invention is to provide in an electronic musical instrument having a series of tone signal sources each of which is adapted to be associated with a frequency divider chain to provide the several difierent octaves of the note provided by that tone signal source, a switching circuit which enables selection in a simple and straightforward manner, an octave of tone signal sources corresponding to a key signature other than the one in which the music is scored and connecting these sources to the frequency divider chains so that the musical output will be transposed as desired without the necessity of operating digitals other than those indicated by the score for example.

A further object of the invention is to provide in an electronic musical instrument utilizing a series of tone signal sources, a switching arrangement in which the tone signal sources are selectively connected to the digitals so that the tones produced by the digitals may be varied in an effective transposition of the music as scored.

In the preferred embodiment of the invention, an electronic organ, there is provided a series of digitals in the form of a keyboard each of which keys the audio signal produced by tone signal source or frequency divider elements to produce the desired combination of musical notes. The digitals adjacent one another produce musical sounds that are a semitone apart. In the musical inice strument of this type, the highest octave of keys (twelve in number) is connected to a series of twelve tone signal sources or primary tone generators and each lower octave of keys is connected to secondary tone generators in the form of a set of aperiodic or nonresonant frequency dividers. The frequency dividers corresponding to each key are arranged in a chain and provide the requisite octave range of the instrument. In accordance with the invention in addition to the series of twelve primary tone generators there is provided an additional series of eleven (or twelve) tone signal sources, which will also be denominated primary tone generators in the following description, whose outputs are related to the principal series to form a continuation of the output tone spectrum. Interposed between the primary and secondary tone generators (the latter being aperiodic dividers) is a switch network inclding twelve bus bars (one for each note of the octave). Each bus bar also has a digital associated with it through which the highest octave of notes are played. Further, there is a set of swelve (or thirteen) ganged switches corresponding to at least the twelve possible key signatures that need to be available for transposition purposes. A thirteenth key may be provided in order to complete the octave by repeating as the highest key, the key at the low end, as is frequently found in the design of keyboards. Each switch set is arranged to selectively connect a series of twelve adjacent tone generators to the bus bars and each bus bar is fixedly connected to a corresponding one of the frequency divider chains. The switch sets are preferably interlocked so that only one of them can be in operated position at any one time. By operating a selected set of switches a series of twelve primary tone generators is connected to the bus bars and the secondary tone generator frequency divider chains. The series of primary tone generators connected to the bus bars and divider chains is easily varied to provide effective transpositions so that a musician may play the keyboard instrument in the easiest manner (in the key of C for example) and produce music transposed up a fifth, for example, to the key of G merely through an appropriate selection of a set of switches. The apparatus provides a simple, easily operated apparatus for accurately changing the key signature of the music so that a musician may adjust the musical output of the instrument to that of the associated instruments, voices or other equipment without any involved mental process of transposition. The apparatus of the invention thus enables the provision of an improved and more versatile electronic musical instrument.

Other objects and advantages of the invention will be seen as the following description of a preferred embodiment thereof progresses in conjunction with the drawing, in which the single figure is a schematic diagram of the primary tone generators, switching apparatus and secondary tone generator divider chains associated with the actuating key members in a preferred embodiment of the invention.

There is shown in the single figure of the drawing a series of primary tone generators 1i), twenty-three in number, which provide two octaves (minus one semitone) of musical tones in semitone intervals. The semitone provided by each generator is indicated by the key value on the block If that represents the tone generator.

Also associated with the musical instrument are twelve chains 12 of frequency divider circuits (indicated by blocks 14, 16, 18) connected in cascade and a series of twelve connector members or bus bars 20. These frequency dividers are of the aperiodic type in that they a0 curately generate output signals of one half the frequency of the input signal over a substantial range of input signal frequencies. Each frequency divider may be a bistable multivibrator, for example, designed to respond to signals applied to its complement input and to have a resulting output of suitable harmonic content. Each bus bar 26 is connected to a corresponding chain of frequency dividers. Thus the lowest bus bar is connected to the leftmost chain (C) of frequency dividers, the next higher bus bar is connected to the chain (C#) of frequency dividers immediately to the right of the C chain, etc. A suitable audio control or gating means, in the form of a key element 22, for example, which is actuated by a digital on the keyboard of the musical instrument is associated with each bus bar and with each secondary tone generator in the frequency divider chains. Thus the audio control key 24 associated with the lowest bus bar, when actuated, produces the highest note of a particular value (C); the audio control key 26 associated with the first frequency divider 14 in the leftmost chain, when actuated, produces the same note value but one octave lower; the key 28 associated with the next divider 16 when actuated also produces the same note in the next lowest octave and so forth. It will be understood that additional secondary tone generators may be added to the frequency divider chains so that the number of octaves of the instrument may be eX- tended as desired. As illustrated these keys 24, 26, 28 are positioned in the C location on the conventional keyboard arrangement. The second bus bar and the second chain of frequency dividers are actuated by keys in the C# keyboard location; the third bus bar and the third chain of frequency dividers are actuated by keys in the D location; etc.

The primary tone generators are adapted to be connected to the audio control mechanism through a switching arrangement which comprises a plurality of ganged switches 30, one switch corresponding to each key signature as indicated on the figure. Each switch element of the ganged switches 36" has a contact 32 permanently secured to the corresponding location on the proper bus bar so that when a ganged switch is operated the series of bus bars 20 are connected to a redetermined series of tone generators through contacts 32. Each primary tone generator is connected to one or more switches 30 so that each primary tone generator note value is connected to a total of twelve switches. Thus the primary tone generator for note E is connected to one switch contact of all twelve switches while the tone generator for the lower P note is connected to only one switch element while the higher F note generator is connected to a contact of each of the other eleven switches. In like manner the lower Fit generator is connected to the elements of two switches and the higher F# generator is connected to elements of the remaining ten switches. The switches 3t! may be perated by push buttons 34, or for instance by the keys of a little single octave keyboard with appropriate coloring of naturals and sharps, or by solenoids, foot controls or other suitable means. These switch operating means are preferably interlocked so that only one ganged switch is operated at any one time. Associated with each switch operator means is a suitable marking or other indication of the resulting degree of effective transposition as the arrangement enables the sound of the music to be shifted upwardly or downwardly as desired in accordance with which set of ganged switches is selected.

For example, if the leftmost ganged switch, denominated 'F, is depressed, as shown in the drawing, the left most primary tone generator F is connected to the C bus bar and the C chain of frequency dividers. Thus depressing any C digital on the keyboard to close the keying means 24, 26, 28 will sound the note F, its octave depending on which particular digital is depressed. Similarly the C# digitals will sound Fit notes, etc. The following table sets forth the various note transpositions which are achieved by operating various pitch selection switches, the body of the table indicating the note that is sounded by depressing the digital in the leftmost column when the horizontal A portion of the wiring and several switches in the central part of the switching arrangement have been omitted in order that a representative portion of the switching arrangement may be clearly illustrated. As the circuitries not shown in detail are connected in the same pattern as that shown it is believed that those of ordinary skill in the art will have no trouble in practicing the invention by following this teaching.

In summary there are twenty-three (or twenty-four) primary tone generators, twelve adjacent ones of which are connected through the switching arrangement to bus bars 29 and divider chains 12 when a single ganged switch 30 is operated. This simple arrangement enables the selcctive shifting of the tones produced as the keyboard digitals of the intsrument are operated through an entire octave in a transposing operation.

Thus it will be seen that the invention provides a very simple and straightforward apparatus which may be used for the selection of various key signatures so that a transposition effect may be easily obtained even by persons comparatively unskilled in the art of playing the electronic musical instrument. It will be understood by those having ordinary skill in this art that various modifications of the disclosed embodiment of the invention may be made therein. Therefore, while there has been shown and described herein a preferred embodiment of the invention it is not intended for the invention to be limited thereto or to details thereof and departures may be made therefrom within the spirit and scope of the invention as defined in the claims.

I claim:

1. In an electronic musical instrument, apparatus for enabling an effective transposition of output musical notes relative to music as scored without the actuation of digitals other than those indicated on the score comprising in combination, a plurality of sets of secondary tone generators, each set including a corresponding plurality of secondary tone generators connected in cascade arrangement, a bus bar conductor means connected to each said set of secondary tone generators, a series of primary tone generators greater in number than the number of sets of secondary tone generators, each said primary tone generator being adapted to generate an electrical signal adapted to produce a predetermined musical note and said primary" tone generators being arranged relative to one another to produce a continuous series of musical notes, ganged switch transposition means adapted to simultaneously connect said bus bar conductor means to a corresponding number of serially related primary tone generators to apply the electrical signals from said primary tone generators to said bus bars and the associated secondary tone generators, a multiplicity of digitals arranged in keyboard relationship in repetitive groups, the number of digitals in each group being equal to the number of bus bar connector means, audio keying means operable by a digital associated with each said secondary tone generator, and audio keying means operable by a digital in the highest group of said keyboard associated with each said bus bar conductor means for enabling the generation of audible musical notes related to the signals provided by the connected primary tone generators in response to the actuation of said digitals.

2. In an electronic musical instrument, apparatus for enabling an effective transposition of output musical notes relative to music as scored without the actuation of digitals other than those indicated on the score comprising in combination, twelve sets of aperiodic frequency divider circuits, the frequency divider circuits in each set being connected in cascade arrangement, twelve bus bar conductor means, one conductor means being connected to each said set of frequency dividers, a series of primary tone generators greater in number than the number of sets of frequency dividers, each said primary tone generator being adapted to generate an electrical signal adapted to produce a predetermined musical note and said primary tone generators being arranged relative to one another to produce a continuous series of musical notes, ganged switch transposition means adapted to simultaneously connect said bus bar conductor means to a corresponding number of serially related primary tone generators to apply the electrical signals from said primary tone generators to said bus bars and the associated frequency dividers, a multiplicity of digitals arranged in keyboard relationship in repetitive groups of twelve each, audio keying means operable by a digital associated with each said frequency divider, and audio keying means operable by a dgital in the highest group of said keyboard associated with each said bus bar conductor means for enabling the generation of audible musical notes related to the signals provided by the connected primary tone generators in response to the actuation of said digitals.

3. In an electronic musical instrument, the combination comprising a series of twenty-three primary tone generators, each said primary tone generator being adapted to produce a predetermined musical note one semitone different from that produced by the immediately adjacent primary tone generator so that said primary tone generators are arranged to produce a continuous series of musical notes in semitone intervals, a set of digitals arranged in keyboard form in octaves with twelve digitals to the octave, twelve sets of secondary tone generators, each set including a corresponding plurality of secondary tone generators arranged to produce that same musical note in descending octave relationship, twelve conductor means, each said conductor means being connected to a particular set of secondary tone generators so that the secondary tone generators of that set are arranged to produce the same note value in lower octaves as is produced by the conductor means to which that set is connected, audio keying means operable by a digital in the highest octave of the keyboard associated with each said conductor means, audio keying means associated with each said secondary tone generator operable by each digital in the lower octaves corresponding to the conductor means to which said secondary tone generator is connected, and switch means adapted to connect said conductor means to twelve serially related primary tone generators for enabling the effective selection of an appropriately related signal from a primary tone generator to provide an output musical note in response to the actuation of a particular digital.

4. in an electronic musical instrument, the combination comprising a series of twenty-three primary tone generators, each said primary tone generator being adapted to produce a predetermined musical note one semitone different from the immediately adjacent tone generator so that said tone generators are arranged to produce a continuous series of musical notes in semitone intervals, a set of digitals arranged in keyboard form in octaves with twelve digitals to the octave, twelve secondary tone generator chains, each said chain change including a plurality of aperiodic frequency dividers connected in cascade arrangement, audio keying means associated With each said frequency divider, each said keying means adapted to be operated by a digital, twelve conductor means, each having associated therewith an audio keying means adapted to be operated by a digital in the highest octave of the keyboard, each said conductor means being connected to a particular frequency divider chain so that the frequency dividers of that chain are arranged to pro duce the same note value in lower octaves as is produced by the connected conductor means, and switch means adapted to connect said conductor means to twelve serially related primary tone generators for enabling the effective selection of a primary tone generator or connected frequency divider to provide an output musical note in response to the actuation of a particular digital.

5. In an electronic musical instrument having a series of digitals arranged in octaves as audio output keying devices for producing individual and distinct musical notes, a pitch selection apparatus including an aperiodic frequency dividing means connected to each digital in all the octaves of the instrument except the highest, the frequency dividing means which are adapted to produce the same notes being connected in a cascaded chain arrangement, means for connecting each said frequency divider chain arrangement to the digital in the highest octave that is adapted to produce the same note as said chain, a series of electronic tone generators adapted to provide signals to said digitals for the production of said musical notes, and switch means adapted to selectively connect a serial group of tone generators equal in number to the number of notes in an octave to said connecting means to pro vide audio signals from said generators via said connecting means and said frequency dividers in response to the actuation of said digitals for enabling an effective transposition relative to said digitals of the key in which music is to be played.

No references cited.

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