US3844192A

US3844192A - Chord control system for electronic organ

Info

Publication number: US3844192A
Application number: US00357389A
Authority: US
Inventors: J Brand; A Carlson; B Penhollow
Original assignee: Thomas International Corp
Current assignee: Thomas International Corp; Kimball International Inc
Priority date: 1973-05-04
Filing date: 1973-05-04
Publication date: 1974-10-29
Anticipated expiration: 1991-10-29
Also published as: GB1448159A; NL168354B; DE2421633B2; IT1011392B; DE2421633A1; NL168354C; NL7405974A; DE2421633C3

Abstract

A semiautomatic chord control system for use with electronic organs having one or more manual keyboards and pedals. A preset major chord switch and a pedal controlled chord switch are provided on the control panel for selective control of different chords to be produced in response to playing of selected root notes on the lower keyboard. In the semiautomatic mode, the organ selectively plays a major, a minor, a seventh, or a minor seventh chord depending on the setting of the chord switches and the selective use of the pedal clavier. The control system plays a chord sequence of the selected type automatically upon the player depressing the desired root note on the lower keyboard.

Description

United States Patent [1 1 Brand et al.

[ CHORD CONTROL SYSTEM FOR ELECTRONIC ORGAN [73] Assignee: Warwick Electronics Inc., Chicago,

Ill.

[22] Filed: May 4, 1973 [21] Appl. No.: 357,389

[52] US. Cl 84/l.0l, 84/1.17, 84/D1G. 22, 84/DIG. 25

[51] Int. Cl. G10h l/00 [58] Field of Search 84/1.01, 1.17, DIG. 22, 84/D1G. 25

[56] References Cited UNITED STATES PATENTS 3,013,462 12/1961 Combs, Sr. 84/D1G. 22

3,305,620 2/1967 Young 84/1.l7

3,470,306 9/1969 Hadclen 84/D1G. 22

3,548,066 12/1970 Freeman 84/D1G. 22

. 3,558,794 1/1971 Hadden 84/l.01

3,565,995 2/1971 Bunger 84/1.l7

3,590,129 6/1971 Freeman 84/1.01 3,665,088 5/1972 Brand et a1. 84/1.01

[ Oct. 29, 1974 Primary Examiner-Richard B. Wilkinson Assistant ExaminerStanley J. Witkowski Attorney, Agent, or Firm1-lofgren, Wegner, Allen, Stellman & McCord [5 7] ABSTRACT A semiautomatic chord control system for use with electronic organs having one or more manual keyboards and pedals. A preset major chord switch and a pedal controlled chord switch are provided on the control panel for selective control of different chords to be produced in response to playing of selected root notes on the lower keyboard. ln the semiautomatic mode, the organ selectively plays a major, a minor, a seventh, or a minor seventh chord depending on the setting of the chord switches and the selective use of the pedal clavier. The control system plays a chord sequence of the selected type automatically upon the player depressing the desired root note on the lower keyboard.

22 Claims, 2 Drawing Figures 1 I c n tu ti PATENTEDum 29 I974 0 W 5 [[FILFI 9 4 w w w W M 3 w 5 3 r 6 6 f NATURALS C#3 C z SYSTEM FOR ELECTRONIC ORGAN BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to eletronic organs, and in particular, to means for automatically playing chords and chord rhythm sequences.

2. Description of the Prior Art In one conventional electronic organ marketed by the assignee hereof, a semiautomatic control is provided for the playing of accompaniment chords and bass notes. In such organs, three keyboards are provided including an upper manual keyboard, a lower manual keyboard, and a pedal clavier. Conventionally, the melody is played on the upper manual keyboard. An automatic control is provided for selectively causing a playing of a chord rhythm sequence in response to the playing of a single note in the lower manual keyboard.

With the automatic control set for manual operation, the organ functions in the manner of a. normal nonchord playing organ. Illustratively, assuming that a musical selection is being played in 3/4 time and that on the first beat of each measure, a C note is played on the pedal clavier and on the second and third beats of each measure a CEG chord is played on the lower keyboard, a rhythm sequence of a C pedal note, CEG chord and CEO chord is provided. With the control set for semiautomatic operation, the rhythm sequence is obtained by the organist simply pressing only the C note on the lower manual keyboard. In this mode of operation, the pedal clavier is'not used and the organist obtains the desired sequence of a C pedal note, CEG chord and CEO chord in 3/4 time simply by playing the C note on the lower keyboard on the first beat of each measure.

cnorm CONTROL The above described semiautomatic control plays only major chords in the various accompaniment sequences. There is, however, a number of different chords which are used in accompaniment sequences which are not major chords, such other chords including minor chords, seventh chords and minor seventh chords. In each case, the chords have the same root note but utilize a different sequence of other chord notes in combination with the given root note.

In one nonchord organ, as shown in U.S. Pat. No. 3,063,327 issued to Eli D. Czarnecki, a pair of horizontal levers are provided adjacent a set of piano keys and are utilized when depressed to cause the organ to play minor fixed chords and major fixed chords, respectively, corresponding to the bass note of the piano key. The levers are played with the forefingers and the base notes are conventionally played with the other fingers and preferably with the thumb.

In U.S. Pat. No. 3,317,649 issued to I. H. Hearne, a manual control for providing a drum or cymbal beat sound to a selected bass note is provided as a result of a playing of "the pedal. The rhythm pattern is keyed to the'organists melody playing and the rhythm accompaniments are selected by the use of appropriate stop tablets.

In U.S. Pat. No. 3,629,481 of David A. Bunger, a touch bar is provided to convert from major to minor chords in any one of five rhythms with rhythm producive effects as desired. A transistorized control responds to the depression of the touch bar to automatically effect the desired chord shift.

In U.S. Pat. No. 2,645,968 of J. M. Hanert, an accordian-type instrument is provided wherein diminished seventh, minor, major, seventh, augmented, and minor seventh chords are provided automatically by a chord tone selector. The instrument is designed for homophonic music as distinguished from polyphonic or contrapuntal music.

The Choshi Enya et al U.S. Pat. No. 3,422,210 shows a chord selecting device for use in eletronic organs wherein the pedals are used to select the root note of a chord and the type of chord is selected by pressing a suitable chord button to obtain either an augmented, a diminished, a seventh, a minor, or a major chord as the result of such a pedal depression.

SUMMARY OF THE INVENTION The present invention comprehends an improved electronic organ chord system wherein pedals may be utilized to select different chord sequences, herein illustratively a minor, a seventh, or a minor seventh chord sequence, by depression thereof concurrently with a selected root note being played on the manual keyboard with the organ set for semiautomatic operation.

More specifically, the invention comprehends the provision of a chord system for such an electronic organ wherein a control is provided permitting the player to obtain a major chord sequence by depressing any one of the keys of a selected portion of the lower manual keyboard. The selected key determines the root note of the chord to be played, and in the normal mode of operation, the major chord will be automatically played by the organ. Thus, for example, if the player presses the C key, a major C chord of CEO will automatically be played.

If, in addition, the player actuates a pedal controlled chord switch, the chord initiated by the depression of the key of the lower keyboard selected section may be changed from the major chord sequence to a minor chord sequence by the player concurrently holding down any one of the pedal clavier naturals. Release of the pedal clavier natural converts the selected chord from a minor chord back to a major chord.

Alternately, with the pedal controlled chord switch turned on, the depression of any one of the pedal clavier sharps will cause the chord to be a seventh chord determined by the selected depressed root key.

Further alternatively, where the pedal controlled chord switch is turned on, the concurrent depression of both a pedal clavier natural and a pedal clavier sharp will cause the chord selected by the depression of the lower keyboard key to be a corresponding minor seventh chord of the selected root note.

The control of the present invention is extremely simple and economical of construction, utilizing a simplified transistorized circuit for providing the above described control of the chord sequences in a novel manner. The control is arranged to have switches associated with the lower keyboard root note keys and the pedal clavier naturals and sharps to effect the desired switching functioning for obtaining the desired different chord sequences as discussed above. The switches are arranged to control the gating of the transistors in a novel and simple manner to provide the desired tone BRIEF. DESCRIPTION OF THE DRAWING Other features and advantages of the invention will be apparent from the following description taken in connection with the accompanying drawing wherein:

FIG. 1 is a perspective view of an electronic organ provided with a chord control system embodying the invention; and i I FIG. 2 is a schematic diagram illustrating the wiring arrangement of the control system with portions broken away to facilitate theillustration thereof.

DESCRIPTION OF THE PREFERRED EMBODIMENT In the exemplary embodiment of the invention as disclosed in FIG. 1 of the drawing, an electronic organ generally designated is shown to include a case 11 having three keyboards, 12, 13 and 14. The upper keyboard l2 may comprise an upper manual keyboard.

' Keyboard 13, may comprise alower manual keyboard. Lower keyboard14 may comprise a pedal clavier including natural pedals IS-and sharp pedals 16. An expression control pedal. 17 is provided in the lower part of case 11 for controlling the volume of the sound produced by the organ. I i

A music rack 18 may be provided on the top of the organ and suitable stop tablets 19 may be provided on the control panel 20 of the case. Control switch means 21 may further beprovided on control panel 20 for providing semiautomatic control of the organ in playing selected chord sequences when desired. The present invention isdirected to an improved control generally designated 22in FIG. 2 for use with the control switches2l for providing an improved facilitated playing of such chord sequences in the semiautomatic mode of operation of the organ. The control provides not only major chord sequences, but also minor chord sequences, seventh chord sequences, and minor seventh chord sequences as desired. Provision of the minor, seventh, and minor seventh chord sequences is obtained by'means of selective depression of the pedals 15 and/or 16 in a novel manner. Selection of the desired accompaniment chords is effected by depression of suitable keys of a section 23 of the lower keyboard 13 in conjunction with suitable setting of the control switches 2I. Thus, for example, should the player de- -sire to play a piece in 3/4 time with the rhythm accompaniment being a sequence of a C note, a CEG chord,

aCEG chord, a C note, etc. sequence, the player may obtain such accompaniment by setting the control switches 21 formanual operation and then sequentially striking the C-pedal with his foot followed by striking the CEG notes in the lower. manual keyboard 13 twice in succession. When the switch means 21 is set for I semiautomatic operation, this sequence is obtained simply by the player depressing only the C note in the lower manual keyboard I3. The C note, in this case, de-

Switchmeans 21 of the present invention permits the player to cause the chords controlled by the selected manual keyboard note to be selectively a first type of chord, such as the major chords discussed above, and a plurality of different additional type chords, such as minor chords, seventh chords, or minor seventh chords based on the selected note. As shown below, control 22 automatically providesleach of four different types of chords for each of the 12 possible selected notes and, thus, automatically provides.48 different chords. Illustratively herein, the selected manual keyboard notes comprise the root notes of the chords.

Minor Seventh Minor seventh chord chord chord CDltG CEGAQ CDliGAit CltE Glt CllF GltB CllE G38 F A DFQAC DFAC Dlt li ii itGAltCli DttFltAtiCli E G EGltBD E GBD FGttC FAOEQ' FGQCDQ: FltACtt FitAltCitE FltACl$E GAttD GBDF GAliDF Gl$BDl$ G50 DltFli GltB DiiFQ B BDttFit BDFQ; BDliFltA BDFttA More specifically, as shown in FIG. 2, each of the keys of the octave '23 is'mechanically connected to a corresponding control switch for connection a plurality of tone generatorsto the outlet line 24. Illustratively, key C is connected toa switch 25 which controls the output from a plurality of C chord generators 26 to the output line 24. Key C is connectedto a switch 27 for controlling the output from a plurality of C chord generators 28 to the output line 24. Each of the other keys of the octave, keys D, D# E, F, F G, G A, A and B are connected through similar switches to similar tone generators and the illustration in FIG. 2 is limited to only the C and C chord generators, it being understood that each of the others is similar thereto except for the different specific tone generators provided for producing the specific appropriate chords for the given note. 4

Thus, as shown in FIG. 2, the C chord generators include

tone generators

29 and 30 for generating the fundamental and overtone frequencies of the note C corresponding to the C key of the keyboard octave 23. Tone generator 31 provides an E note, tone generator 32 provides a D,# note, tone generator 33 provides a G note, and tone generator 34 provides an A A} note.

Switch means 21 includes a major chord switch 35 and a pedal control chord switch 36. The natural pedals 15 of the 'pedal clavier .14 are connected respectively to different ones of a plurality of natural switches 37 and sharp pedals 16 are connected respectively to different ones of a plurality of sharp switches 38.

With switches 35 and 36 in the OFF position as shown in FIG. 2, pressing of C key 23C closes switch 25 so as to connect

C tone generators

29 and 30 to the output line 24, thereby producing the fundamental and overtone frequencies of the desired note C. If it is desired to produce a C major chord rather than the single note C, the major chord switch 35 is thrown from the position of FIG. 2 to be connected to a l5-volt DC power supply 39, placing a IO-volt bias on 'a line 40. This bias is applied to line 40 through a resistor 41 and through a second resistor 42 to a diode 43 which is resultingly forward biased to pass a signal from G tone generator 33 to switch 25. Concurrently, the -volt bias of line 40 is applied to the emitter Me of a transistor 44 through a connecting line 45. The base 44b of transistor 44 is connected through a resistor 46 to a line 47 which, in turn, is connected through the closed series of switches 37 to ground G so that transistor 44 is saturated and an associated transistor 48 is biased off. Resultingly, a gating signal is'applied to a diode 49 through a resistor 50 connected by a line 51 to the collector 44c of transistor 44 and collector 480 of transistor 48. Base 48b of transistor 48 is connected through a resistor 52 to line 47 and emitter 48e of transistor 48 is connected to ground G. Base 48b of transistor 48 is further connected through a resistor 53 to ground.

The forward biasing of diode 49 permits E tone generator 31 to pass a signal through a resistor 54 to switch 25. The G tone from generator 33 is passed through a resistor 55 to switch 25 and assuming that the C key 23C is depressed, the fundamental and overtone C notes produced by

tone generators

29 and 30, the E note produced by tone generator 31, and the G note produced by tone generator 33 will concurrently be delivered through output 24 for soundinga CEG chord as a result of the depression of only the C key 23C.

If the organist wishes to play a C minor chord comprised of the C, D and G notes, the switch 36 is thrown from the positionof FIG.- 2 to engage a contact 360 connected between resistor 41 and l0-volt Zener diode 56 which, in turn, .is connected to ground. This places a l0-'volt bias on aIlin'e S'l 'cOnnected to normally open fixed contacts 38a of

sharp switches

38 and 37a of natural switches 37. Subsequentdepression of any or all of the natural pedals causes line 57 to be connected to line 47, thereby applying the lO-volt biasing voltage through a resistor 58 to a diode 59 which is resultingly forwardly biased to cause tone generator 32 to provide a D .note through a resistor 60 to switch 25. 40

At the same time, the biasing voltage now applied to line 47 gates on transistor 48 and concurrently biases off transistor 44 so that the voltage on line 51 is removed to remove the bias from diode 49 thereby preventing passage of a tone from generator 31 when the key 23C is depressed. Therefore, the resulting chord will now become a C minor chord of C, D and G tones.

Alternatively, if a C seventh chord is desired, the player depresses any one or more of the pedal sharps 16 so as to close corresponding ones of the sharp switches 38 to engage its corresponding fixed contact 38a thereby providing a lO-volt biasing voltage to a line 61 which is connected through a resistor 62 to a diode 63 which, when forwardly biased by this voltage, permits tone generator 34 to provide an A 1% tone through a resistor 64 to switch 25. Thus, the A 4* tone is added to the CEG tones to sound a C seventh chord, CEGA a If a minor C seventh chord is to be sounded, the user merely depresses any one or more of the pedal naturals l5 concurrently with depression of any one or more of the pedal sharps 16 so that one or more of the switches 37 is connected to its associated fixed contact 370 and one or more of the switches 38 is connected to its associatedfixed contact 38a to provide l0-volt biasing voltage to both

lines

47 and 61 so that the resultant chord will be comprised of the CD G and A it tones upon depression of the key 23C.

Similarly, if a C it major chord is to be played, the C fundamental tone generator 65 and C at overtone generator 66 are connected through switch 27 to the out e i e 24. M2911 .sierressi9a9fjh9 Q.#-. @r.2#- Additional tone generators of group 28 include F tone generator 67, E tone generator 68, G 1* tone generator 69 and B tone generator 70. To provide a C major chord,

tone generators

65, 66, 67 and 69 are actuated to produce the C F and G tones through switch 27 to output line 24. Thus, tone generator 63 is connected to switch 27 through a resistor 71 and tone generator 66 is connected to switch 27 through a resistor 72, line 51 is connected to a diode 73 through a resistor 74, and thus, when biasing voltage is applied to line 51, tone generator 67 provides an F tone through a resistor 75 to switch 27. Line 47 is connected through a resistor 76 to a diode 77 and, thus, when biasing voltage is pro vided on line 47, tone generator 68 produces an E note through a resistor 78 connected to switch 27. Line 40 is connected through a resistor 79 to a diode 80 and,

thguhgnbiasing vol t a g e is applied to line 40, a G# tone is provided through a resistor 81 to switch 27? a lO-volt biasing voltage to line while leaving switch 36 as-shown in 2 will produce a C#, F, G#

chord upon depression of the C key 23C 5* lie pr e ssion of key 23C when both switches 35 and 36 are thrown from the position of FIG. 2, permits the C a major chord to be converted selectively to a C E, G minor chord by depression of any one or more of the natural pedals 15, to be converted to a C a seventh chord, C ii FG B by depression of any one of the sharp pedals 16, or to be converted to a minor seventh chord, C EG B by a concurrent depression of one or more natural pedals 15 and one or more sharp pedals 16.

Each of the other keys of the octave 23 will thusly produce similar selected major, minor, seventh, and minor seventh chords based on the corresponding root note determined by the particular key depressed. Thus, 12 switches corresponding to the

switches

25 and 27 are provided in association with 12 different root note chord-producing tone generator sets with the C root note and C 4' root note sets only being illustrated.

By utilization of the control switches and pedal clavier as chord modifier or conditioning means, the present invention permits an improved facilitated playing of different types of chords based on selective root notes 5 tremely simple and straightforward, effectively minimizing cost and maintenance while yet providing the highly desirable improved facilitated playing of the organ as discussed above.

.al is so depressed.

Pedals-include'a'plurality of naturalpedalsand a plural ity iof sharp pedalsi said modifier rheans'changing the chord to o'ne-t'yp'e wh'e'n'a natural pedalis so depressed andLtoa'differe n't type when a sharp pedal is so de- I The foregoing-disclosure of sp'ecific'embodiments is illustrative of: the broad inventive concepts comprehend d y t n en o 1 1 (The-embodiments of theinven tion in-which an exclusive propertyor privilege is claimed-are 'defined as fol a lowsi {Cu ilv'i' 1-.'ln an electronicorgah having a manual keyboard, and pedals aisemiautomatic;chord control system comprising; selector means-for-producing selectively either a single correspondingnote ora first type of chord having-said note as the root note thereof as a result of depression of any one of a set of keys of the keyboard;

and modifier-means for changing at leastone of the notesof said schord to anothet type. of chord-as a result of =d epression, of ai pedal with said'selector means arranged to produce-said chord.

thereby change said first i/Pet a second yp -J a 12. The electronic organ of claim l iwhereinljsaid firstchord' type is a major chord; 1,

13. The electronic organ of claim' 11 wherein said I second keyboard includes 7 a: first: group of keys corresponding tothe na'tural tones'in a musical scale and, a

' second group of keys corresponding to; the sharp tones in a musical scale'and wherein actuation of at least one of said first group of keys changes themajor chord to a minor chord. i 14. The electronic organ of claim 13 wherein actuationof at' least oneof said "second group flof keys changesvthe'major chord to a seventh chord.

, 2 -.I-T he organ controlsystem .of claiml wherein said ped'als-j inelude a pluralityof natural pedals andia plurality' v of 'sharp pedals, said modifier; means changing the chordto one type when anatural pedal is so depressed a' differentityp'e when; a sharp pedal'is so I der i j sed," i- I a v The crgan'control systernof 1 wherein said modifierrmeaiischanges the chord toja single said another?typegwhenevehany oneiof a plurality of said ped- The'organ'fcon rol claim I -wherein said masseuse to-afurther different type when both a naturaljpedal andagsharp :p'edal are concurrently so'depressedi5. 'Thevo'rgan control system claim 1 wherein means are provided for-selectively causing said depression of a keyof the keyboard to play'a succession of notes in apreselec'ted rhythm sequence, Y

6x1 he organ controlsystem of claim "1 wherein said I another-typeof chord fcomprises a i ninor chord; I 7;:The-organcontrol system of ,claim 1 wherein said another typeof' chord comprises a seventh I chord.

- v 8. The organ control system of claim 1 wherein said pedals include a plurality of naturalpedals and a' plural ity of; sharp pedals,= said modifier means changing the chord to minor when a natural pedal is so depressed, to a seventh when a sharp pedal is so depressed, and to a minor. seventh when both a natural pedaland a sharp v pedal are concurrently so depressed.

'9. The organ control system of claim -1 wherein said lower manual keyboard.-

' Th f ll C rol system of claim 1 wherein said her typfif f hotd hasisaid note as the root nm ther of; t. I

'l l'. ln anelectronicorgan, a semiautomatic chord control system comprising: a first manualkeyboard 3 having a plurality of keys; meansfor causing a chord of a first'chord type to'be sounded in response; to actuation of anyone of said keys; said chord having a root corresponding to the activated key; a second vkeyboard having a plurality of keys; and means forconditioning I said 7 secondkeyboardto, cause the contemporaneous actuation of any oneof said plurality of keys thereof to change at leastone of the notes of said chord and .f r ch ngifig' he firstchot typ 10' as c ndshsr ftyp as an incident of depressionofany number ofsaid individual keys .ofsaidsejcond'keyboard, I

17. The electronics, organ ofcl fm; 16 wherein said second switch means is connectedto] a' third, switching means comprising a bistableflip flop'circuit. j

18. The electronic organof lairh 14 wherein said conditioning means i ncludes'circuit'nieans for. changing a major chord to a seventh chord comprisingfirst switching means, second switching means defined by a plurality of series connected single pole, d ouble throw switchesvassociatedone each with individual keys of I I v organ includes an-upper manual keyboard and alower 1 manual keyboard-and said key'comprises a key of said a different chord.

said second keyboard and control means operatively associated with said switchingmeans for converting the major chord to a seventhchord as an incident of ,depression of any number of said individual keys of said second keyboard I 9. The electronic organ of claim lljwherei'n' the first keyboard includes a control 'sectibfn, said plurality of keysfor selecting a chord comprising the keys of said control section.

20. In an electronic organ having a pedal clavier, a

plurality of different tone generators and a keyboard for playing selectively any one of a plurality of different major chord root notes and selector means selectively causing the depression of any selected root note key of a set of keys of-said keyboard to actuate a preselected corresponding set} of the tone generators to sound a correspondingly major chord of the selected root note, a chord'control system comprising! electronic switch means for controlling selective actuation of the tone generators; a plurality of series connected switches controlled one each by the individual pedals of the pedal clavier; and circuit means for selectivelyoperating different ones of .said electronic switch means as a result of depressing any of the pedal clavier pedals to change at least one note of the selected major chord to 21 Theelectronic organ system of claim 20 wherein said pedal clavier includes natural and sharp pedals, said series connected switches include a first set con- 10 trolled by natural pedals of the pedal clavier and a second set controlled by sharp pedals of the pedal clavier, and said circuit means is arranged to provide a different type of chord based on the selected root note as an incident of depression selectively of either a natural pedal or a sharp pedal, or both concurrently.

Claims

1. In an electronic organ having a manual keyboard, and pedals a semiautomatic chord control system comprising: selector means for producing selectively either a single corresponding note or a first type of chord having said note as the root note thereof as a result of depression of any one of a set of keys of the keyboard; and modifier means for changing at least one of the notes of said chord to another type of chord as a result of depression of a pedal with said selector means arranged to produce said chord.

2. The organ control system of claim 1 wherein said pedals include a plurality of natural pedals and a plurality of sharp pedals, said modifier means changing the chord to one type when a natural pedal is so depressed and to a different type when a sharp pedal is so depressed.

3. The organ control system of claim 1 wherein said modifier means changes the chord to a single said another type whenever any one of a plurality of said pedals is so depressed.

4. The organ control system of claim 1 wherein said pedals include a plurality of natural pedals and a plurality of sharp pedals, said modifier means changing the chord to one type when a natural pedal is so depressed and to a different type when a sharp pedal is so depressed, and to a further different type when both a natural pedal and a sharp pedal are concurrently so depressed.

5. The organ control system claim 1 wherein means are provided for selectively causing said depression of a key of the keyboard to play a succession of notes in a preselected rhythm sequence.

6. The organ control system of claim 1 wherein said another type of chord comprises a minor chord.

7. The organ control system of claim 1 wherein said another type of chord comprises a seventh chord.

8. The organ control system of claim 1 wherein said pedals include a plurality of natural pedals and a plurality of sharp pedals, said modifier means changing the chord to minor when a natural pedal is so depressed, to a seventh when a sharp pedal is so depressed, and to a minor seventh when both a natural pedal and a sharp pedal are concurrently so depressed.

9. The organ control system of claim 1 wherein said organ includes an upper manual keyboard and a lower manual keyboard and said key compriSes a key of said lower manual keyboard.

10. The organ control system of claim 1 wherein said another type of chord has said note as the root note thereof.

11. In an electronic organ, a semiautomatic chord control system comprising: a first manual keyboard having a plurality of keys; means for causing a chord of a first chord type to be sounded in response to actuation of any one of said keys, said chord having a root corresponding to the activated key; a second keyboard having a plurality of keys; and means for conditioning said second keyboard to cause the contemporaneous actuation of any one of said plurality of keys thereof to change at least one of the notes of said chord and thereby change said first chord type to a second chord type.

12. The electronic organ of claim 11 wherein said first chord type is a major chord.

13. The electronic organ of claim 11 wherein said second keyboard includes a first group of keys corresponding to the natural tones in a musical scale and a second group of keys corresponding to the sharp tones in a musical scale and wherein actuation of at least one of said first group of keys changes the major chord to a minor chord.

14. The electronic organ of claim 13 wherein actuation of at least one of said second group of keys changes the major chord to a seventh chord.

15. The electronic organ of claim 13 wherein contemporaneous actuation of at least one key of said first group of keys and at least one key of said second group of keys changes the chord to a minor seventh chord.

16. The electronic organ of claim 11 wherein said conditioning means incldues circuit means for changing said first chord type to said second chord type comprising first switching means, second switching means defined by a plurality of series connected single pole, double throw switches associated one each with the individual keys of said second keyboard, and control means operatively associated with said switching means for changing the first chord type to a second chord type as an incident of depression of any number of said individual keys of said second keyboard.

17. The electronic organ of claim 16 wherein said second switch means is connected to a third switching means comprising a bistable flip flop circuit.

18. The electronic organ of claim 14 wherein said conditioning means includes circuit means for changing a major chord to a seventh chord comprising first switching means, second switching means defined by a plurality of series connected single pole, double throw switches associated one each with individual keys of said second keyboard and control means operatively associated with said switching means for converting the major chord to a seventh chord as an incident of depression of any number of said individual keys of said second keyboard

19. The electronic organ of claim 11 wherein the first keyboard includes a control section, said plurality of keys for selecting a chord comprising the keys of said control section.

20. In an electronic organ having a pedal clavier, a plurality of different tone generators and a keyboard for playing selectively any one of a plurality of different major chord root notes and selector means selectively causing the depression of any selected root note key of a set of keys of said keyboard to actuate a preselected corresponding set of the tone generators to sound a correspondingly major chord of the selected root note, a chord control system comprising: electronic switch means for controlling selective actuation of the tone generators; a plurality of series connected switches controlled one each by the individual pedals of the pedal clavier; and circuit means for selectively operating different ones of said electronic switch means as a result of depressing any of the pedal clavier pedals to change at least one note of the selected major chord to a different chord.

21. The electronic organ system of claim 20 wherein said pedal clavier includes natural and sharp pedals, said series connected Switches include a first set controlled by sharp pedals of the pedal clavier, and said circuit means is arranged to provide a different type of chord based on the selected root note as an incident of depression selectively of either a natural pedal or a sharp pedal.

22. The electronic organ system of claim 20 wherein said pedal clavier includes natural and sharp pedals, said series connected switches include a first set controlled by natural pedals of the pedal clavier and a second set controlled by sharp pedals of the pedal clavier, and said circuit means is arranged to provide a different type of chord based on the selected root note as an incident of depression selectively of either a natural pedal or a sharp pedal, or both concurrently.