US3766305A - D.c. keyed high low select preference system for polyphonic electrical musical instruments - Google Patents

D.c. keyed high low select preference system for polyphonic electrical musical instruments Download PDF

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Publication number
US3766305A
US3766305A US00272437A US3766305DA US3766305A US 3766305 A US3766305 A US 3766305A US 00272437 A US00272437 A US 00272437A US 3766305D A US3766305D A US 3766305DA US 3766305 A US3766305 A US 3766305A
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note
transistors
impedance
group
output
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Expired - Lifetime
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US00272437A
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English (en)
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R Schrecongost
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Marmon Co
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Hammond Corp
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    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10H—ELECTROPHONIC MUSICAL INSTRUMENTS; INSTRUMENTS IN WHICH THE TONES ARE GENERATED BY ELECTROMECHANICAL MEANS OR ELECTRONIC GENERATORS, OR IN WHICH THE TONES ARE SYNTHESISED FROM A DATA STORE
    • G10H1/00—Details of electrophonic musical instruments
    • G10H1/18—Selecting circuits
    • G10H1/22—Selecting circuits for suppressing tones; Preference networks
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S84/00—Music
    • Y10S84/02—Preference networks

Definitions

  • ABSTRACT A transistorized high-low note select system for keyboard type electrical musical instruments which provides for direct current operation with or without control of the attack and decay envelope and supplies the alternating current signals for the highest and/or lowest notes of a group of notes played together respectively to a high note lead or a low note lead or to independent leads for each.
  • this is for the purpose of supplying the high note signal of group of keys played simultaneously to be sounded as a solo note, or high and low notes of an accompaniment chord to be sounded in unison or with frequency division as a pair of bass notes one or two octaves down from a three or four note chord being held on a keyboard for example.
  • the system may also be used to supply the lowest note with frequency division as a single bass note or for similar purposes.
  • the keyboard may be conventional.
  • the present invention may be considered as an improvement over the system of Bode, U.S. Pat. No. 2,874,286 and as a substitute therefor, for example, in musical instruments of the type of Tennes et al. U.S. Pat. No. 3,567,838.
  • the system of the previously referred to Tennes et al patent provides a keyboard type musical instrument in which holding the keys of a chord of three or four notes with the left hand supplies the appropriate three of four note signals together to a chord lead.
  • a preference system of the Bode type supplies the signal for the lowest note of the group to a low note select lead and the signal for the highest note of the group to a high note select lead.
  • An automatic rhythm system of the type which sounds drum, cymbal, blocks, and similar untuned sounds according to any of several selected programs is connected such that at appropriate intervals during the program which may include various of the untuned instrumental sounds, the programmer also sounds whatever signals are on the chord lead, the low note select lead and the high note select lead.
  • the signals on the low note select lead and the high note select lead are passed through one or preferably two stages of binary frequency division so that the selected low and high notes sound one or preferably two octaves down from the chord.
  • the effect is such that by simply holding the keys for a three or four note chord with the left hand, and at appropriate times changing from one chord to another, the system automatically according to whatever program is selected, keys orsounds the chord, a low bass note and a high bass note. This eliminates the need to play the chord at the proper time and also eliminates the need for bass pedals and the skill normally required for their actuation.
  • Bode preference system is based upon what is known as A.C. keying, that is, the playing key contacts make and break the alternating current signal circuits.
  • A.C. keying There are disadvantages associated with A.C. keying, such as problems'with transients and particularly an inability to exercise control over the keying envelope. There is no convenient way for sustaining the tone with a gradually decaying envelope after a key has been released, for example.
  • the present invention overcomes such problems by providing a D.C. actuated preference circuit. That is, the playing keys make and break a D. C. circuit which turns transistors on and off with or without sustain as desired. For instance, the control D.C.
  • DC. control signals for a group of keys played together supply note signals for the lowest, the highest or both notes of the group.
  • selected note signals, with or without sustain, can be frequency divided, multiplied, formanted and can have any desired envelope characteristic provided by a following percussive or sustain keyer.
  • FIG. ii is a circuit diagram of a preference system which includes features of the present invention.
  • FIG. 2 is a diagram showing the circuit of FIG. I modified to provide sustain of the envelope after a playing key has been released.
  • FIG. I of the drawings a group of transistors are indicated individually at A, B, C, I), N. Each of these is the active element of a keyer or gate for one note of the portion of the musical instrument to which the preference system of the invention is applied.
  • the preference system may be applied to the accompaniment section of an organ and cover the lowest group of twenty playing keys, such that if a chord of three or four keys is played within this section, the preference system will select the lowest and the highest notes of any such chord.
  • the transistors A-D may be considered representative of the lowest four keyers for this section and N the highest, it being understood that there will be others between D and N which are not shown since all are identical.
  • the base of transistor A is connected to ground, which here represents the other side of the circuit, through a resistor and through resistor 12 to one side of a set of playing key contacts 14, the other side of which is connected to a DC. keying bus 16.
  • Branch loads 15 are the main keying leads for connection to the other customary organ keyers, not shown which key the noteto be played in the usual organ fashion, that is, in any of the regular organ modes.
  • the emitter is connected to ground through a resistor 18 and to a terminal 20 which may be considered as the source of the particular music signal to be keyed. Each of these terminals, 20, is connected to one side of the appropriate tone signal generator.
  • the other side of each generator, as is customary, is connected to the other side of the circuit, normally referred to as ground.
  • the transistor A for keying the lowest note of the group, has its collector connected through a resistor 22 to a low note select output terminal 24, connected in turn to the input of a preamplifier 26 having an output
  • the collector of the second transistor B is connected to the collector of A through a resistor 28 and to the collector of C through a resistor 30.
  • C collector is also connected through a resistor 32 to the collector of D which is connected to the collector of the next in the series'through resistor 34, and so on to the collector of transistor N, the last in the series.
  • the collector of transistor N is connected through resistor 36 to a high note select output terminal 38. This output terminal is connected to the input of preamplifier 40 having an output 41.
  • Suitable values for the constants of this particular circuit are as follows. Resistors 10, 10 K; resistors 18, 100 ohms; resistors 12, 100 K; and resistors 22, 28, 30, 32, 34 and 36, 22 K.
  • the keying voltage on bus '16 may suitably he -28 v.
  • the preamplifiers 26 and 40 have a relatively high input impedance of the order of ten times or more of the total of the resistance in the line between the two output terminals 24 and 38. If, as in the example given, there are twenty keyers, and, therefore, 21' resistors in series of 22 K each, a total of 462 K,a suitable value for the input impedance of the amplifiers is megohms or so. v
  • the outputs 27 and 41 from the preamplifiers may be connected to any desired circuits such as frequency dividers and suitable formants to'obtain bass notes re- .lated to the chord being held for example.
  • automatic programmer can at appropriate intervals switch the preamplifier outputs to a bass note frequency divider leading to the output system of the organ or if desired, the programmer or a multivibrator or some similar system can switch the low and high terminals 24 and 38 to the input of a single preamplifier. It will be appreciated, of course, that this invention is concerned with the preference system and not particularly with the specific use made of the high and low note signals selected by the system,
  • the system operates as follows. Assuming the playing key contacts 14 are closed for transistor A, this applies the -28 v. on bus 16 to the to one voltage divider composed of 100 K resistor 12 and I0 K resistor 10. The voltage appearing at the base' of transistor A is, therefore, about -2.8 v. which causes the transistor to conduct. The portion of the F,signal at terminal not grounded through resistor 18 is therefore conducted to the junction between resistors 22 and 28. Because of the high impedance of the amplifiers 26 and 40, it makes little difference whether the signal passes through resistor 22 to amplifier 26 or whether it passes through twenty resistors of the same value to amplifier 40.
  • the resistance is 22 K whereas on the other it is 440 K, but both are small as compared with the amplifier input impedances of 5 megohms or so.
  • FIG. 2 shows the circuit of a single transistor and is like those of FIG. ll excepting that a capacitor 50, shown connected across resistors 10 and 12, will remain charged after key release.
  • a similar capacitor is connected across each of the other pairs of resistors 10 and 12 of the preference circuit.
  • closing key contacts 14 charges the capacitor 50 and turns on the transistor.
  • capacitor 50 When the playing key is released and the contacts open, capacitor 50 will remain charged, and consequently the note signal will remain on, long enough for subsequent gating or envelope shaping of the output signal or the frequency divider outputs by means of a conventional unitary keying system.
  • A- conventional snubbing circuit may be required to insure that only the last-played note remains on.
  • the preference system with this simple holding circuit can have the preamplifier outputs connected through unitary keyers, which may be conventional.
  • unitary keyers can give the selected notes any desired envelope characteristic such as percussive (a struck or plucked string effect) or sustain (a gradual decay after the key is released) or something similar, the purpose of the capacitors 50 being to hold the note after key release long enough for the unitary keyers to impart their characteristic envelope.
  • This simple holding feature for the preference circuit is illustrative of the possibilities for control of the keying envelope which is characteris tic of this invention and one of its important features.
  • the transistors shown may be any of several types including field effect transistors if desired.
  • preference circuit of this invention has been described in conjunction with a system which selects both the high and low notes of a group of keys played together, it will be appreciated that the system somewhat abridged can supply only the high or the low note if that is all that is desired. For example, if only the high note is needed, the low end portion of the circuit including the resistor 22, terminal 24 and preamplifier 26 can be eliminated. It will also be appreciated that even though emphasis has been placed upon use of the system to supply high and low bass notes, this is for the purpose of illustrating a typical embodiment. As mentioned earlier, preference circuits have other uses and it is considered that the invention is in the D.C. preference circuit itself, rather than in the uses to which the output of the circuit is put.
  • a plurality of sources for a group of alternating current signals a plurality of actuated control elements one for each of said signals, a plurality of transistors, one for each of said signals, a source of D.C. keying potential, D.C. circuit means including said control elements connected individually from said D.C.
  • each of said transistors having an input circuit connected to receive a signal from one of said sources and an output, an output line consisting of a group of series connected substantially identical resistors with one end of said group connected to a terminal, the outputs of said transistors being connected individually to the junctions between said resistors, high impedance output circuit means connected to said terminal, each of said input circuits for said transistors having a low impedance connection in shunt with its signal source, the impedance of said high impedance output circuit means being many times the total impedance of all of the series connected resistors and the impedance of each of said series connected resistors being many times the impedance of each of said low impedance connections.
  • each of said input circuits includes a low impedance resistor connected between the transistor signal input and ground.
  • each of said sustain circuits including a capacitor connected to be charged when the control element is actuated and to discharge at a controlled rate when the control element is deactuated.
  • a plurality of sources for a group of musical tone signals a plurality of playing keys one for each of said signals, each of said keys having a contact set, a plurality of transistors, one for each of said signals, a source of D.C. keying potential, D.C. circuit means including said contact sets connected individually from said D.C.
  • each of said transistors having a signal input circuit connected to receive a signal from one of said sources and an output line consisting of a group of series connected substantially identical resistors with the first of said group connected to a low note select terminal and the last of said group connected to a high note select terminal, said group of resistors having one more resistor than there are transistors, the output of the transistor for the lowest note of the group being connected to the junction between the first and second resistor, the output form the transistor for the next higher note being connected to the junction between the second and third resistor, the output from the transistor for the next higher note being connected to the junction between the third and fourth resistor and so on for the outputs of all of said transistors with the output of the transistor for the highest note of the group connected between the last and the next to last resistors of said group, high impedance output circuit means connected to said low note select and said high note select terminals, each of said signal input circuits for said transistors having a low
  • each of said signal input circuits includes a low impedance resistor connected between the transistor input and ground.
  • said D.C. circuit means includes a series resistor network and capacitor in paralled thereto connected between each said contact sets and the other side of the circuit, and an intermediate voltage point on said resistor network connected to said transistor.
  • said D.C. circuit means includes a series resistor network and capacitor in parallel thereto connected between each said contact sets and the other side of the circuit, and an intermediate voltage point on said resistor network connected to said transistor.

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  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Acoustics & Sound (AREA)
  • Multimedia (AREA)
  • Electrophonic Musical Instruments (AREA)
US00272437A 1972-07-17 1972-07-17 D.c. keyed high low select preference system for polyphonic electrical musical instruments Expired - Lifetime US3766305A (en)

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US27243772A 1972-07-17 1972-07-17

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US (1) US3766305A (zh)
JP (1) JPS5620559B2 (zh)
AU (1) AU5769573A (zh)
BR (1) BR7305346D0 (zh)
CA (1) CA993235A (zh)
DE (1) DE2336425A1 (zh)
GB (1) GB1404909A (zh)
IT (1) IT991252B (zh)
NL (1) NL7309761A (zh)
ZA (1) ZA734526B (zh)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3918342A (en) * 1973-09-14 1975-11-11 Keio Giken Kogyo Kabushikikais Monophonic electronic musical instrument of equal tempered scale
US3921491A (en) * 1973-04-25 1975-11-25 Alfred B Freeman Bass system for automatic root fifth and pedal sustain
US3948137A (en) * 1974-03-15 1976-04-06 Nippon Gakki Seizo Kabushiki Kaisha Pitch determining voltage signal generating circuit for a voltage controlled type electronic musical instrument
US4016792A (en) * 1974-03-04 1977-04-12 Hammond Corporation Monophonic electronic musical instrument
US4064777A (en) * 1975-09-08 1977-12-27 Roland Corporation Circuit for preferentially selecting highest and lowest tones
US4065993A (en) * 1974-12-26 1978-01-03 Nippon Gakki Seizo Kabushiki Kaisha Electronic organ with a three-finger chord and one-finger automatic chord playing mode selector
US4159663A (en) * 1976-10-28 1979-07-03 Nippon Gakki Seizo Kabushiki Kaisha Electronic musical instrument with different types of tone forming systems
US4186637A (en) * 1977-09-22 1980-02-05 Norlin Industries, Inc. Tone generating system for electronic musical instrument

Citations (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2429226A (en) * 1942-09-14 1947-10-21 Hammond Instr Co Electrical musical instrument
US2468062A (en) * 1944-12-23 1949-04-26 Hammond Insturment Company Electrical musical instrument
US2645968A (en) * 1950-06-23 1953-07-21 Hammond Instr Co Electrical musical instrument
US2710555A (en) * 1948-12-28 1955-06-14 Martin Constant Electronic musical instrument
US2874286A (en) * 1955-07-29 1959-02-17 Estey Organ Corp Preference network
US2933004A (en) * 1952-08-29 1960-04-19 Hammond Organ Co Combined piano and electrical monophonic instrument
US3051032A (en) * 1959-03-18 1962-08-28 Hammond Organ Co Single manual double countermelody electrical musical instrument
US3247310A (en) * 1962-09-13 1966-04-19 Chicago Musical Instr Co Musical instrument
US3260784A (en) * 1963-11-07 1966-07-12 Wolfgang J Wehrmann Electronic musical instrument having one or more keyboards
US3283057A (en) * 1964-06-26 1966-11-01 Seeburg Corp Keyboard oscillator circuit
US3395242A (en) * 1965-07-08 1968-07-30 Baldwin Co D H Preference circuit
US3417188A (en) * 1965-06-23 1968-12-17 Baldwin Co D H Preference circuit for electronic musical instrument utilizing pulse amplitude discrimination and zero-crossing detector
US3432607A (en) * 1964-08-17 1969-03-11 Joh Mustad Ab Bass control of electronic musical instruments
US3470306A (en) * 1965-07-01 1969-09-30 Baldwin Co D H Bass register keying system
US3476864A (en) * 1966-03-09 1969-11-04 Baldwin Co D H Electronic organ reiteration system utilizing a zero-crossing preference circuit
US3509262A (en) * 1966-07-11 1970-04-28 Baldwin Co D H Bass register keying system employing preference networks
US3511917A (en) * 1967-04-10 1970-05-12 Seeburg Corp Voltage selection arrangement wherein same contacts switch selectable d.c. pitch potential and constant a.c. for control function
US3538804A (en) * 1968-06-06 1970-11-10 Hammond Organ Co Electronic solo instrument having high-note guard circuit
US3567838A (en) * 1969-11-12 1971-03-02 Hammond Corp Musical instrument rhythm system having provision for introducing automatically selected chord components
US3665089A (en) * 1970-12-17 1972-05-23 Tonus Inc Music synthesizer keyboard
US3719767A (en) * 1970-11-29 1973-03-06 Matsushita Electric Ind Co Ltd Signal-selecting system for a keyboard type electronic musical instrument

Patent Citations (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2429226A (en) * 1942-09-14 1947-10-21 Hammond Instr Co Electrical musical instrument
US2468062A (en) * 1944-12-23 1949-04-26 Hammond Insturment Company Electrical musical instrument
US2710555A (en) * 1948-12-28 1955-06-14 Martin Constant Electronic musical instrument
US2645968A (en) * 1950-06-23 1953-07-21 Hammond Instr Co Electrical musical instrument
US2933004A (en) * 1952-08-29 1960-04-19 Hammond Organ Co Combined piano and electrical monophonic instrument
US2874286A (en) * 1955-07-29 1959-02-17 Estey Organ Corp Preference network
US3051032A (en) * 1959-03-18 1962-08-28 Hammond Organ Co Single manual double countermelody electrical musical instrument
US3247310A (en) * 1962-09-13 1966-04-19 Chicago Musical Instr Co Musical instrument
US3260784A (en) * 1963-11-07 1966-07-12 Wolfgang J Wehrmann Electronic musical instrument having one or more keyboards
US3283057A (en) * 1964-06-26 1966-11-01 Seeburg Corp Keyboard oscillator circuit
US3432607A (en) * 1964-08-17 1969-03-11 Joh Mustad Ab Bass control of electronic musical instruments
US3417188A (en) * 1965-06-23 1968-12-17 Baldwin Co D H Preference circuit for electronic musical instrument utilizing pulse amplitude discrimination and zero-crossing detector
US3470306A (en) * 1965-07-01 1969-09-30 Baldwin Co D H Bass register keying system
US3395242A (en) * 1965-07-08 1968-07-30 Baldwin Co D H Preference circuit
US3476864A (en) * 1966-03-09 1969-11-04 Baldwin Co D H Electronic organ reiteration system utilizing a zero-crossing preference circuit
US3509262A (en) * 1966-07-11 1970-04-28 Baldwin Co D H Bass register keying system employing preference networks
US3511917A (en) * 1967-04-10 1970-05-12 Seeburg Corp Voltage selection arrangement wherein same contacts switch selectable d.c. pitch potential and constant a.c. for control function
US3538804A (en) * 1968-06-06 1970-11-10 Hammond Organ Co Electronic solo instrument having high-note guard circuit
US3567838A (en) * 1969-11-12 1971-03-02 Hammond Corp Musical instrument rhythm system having provision for introducing automatically selected chord components
US3719767A (en) * 1970-11-29 1973-03-06 Matsushita Electric Ind Co Ltd Signal-selecting system for a keyboard type electronic musical instrument
US3665089A (en) * 1970-12-17 1972-05-23 Tonus Inc Music synthesizer keyboard

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3921491A (en) * 1973-04-25 1975-11-25 Alfred B Freeman Bass system for automatic root fifth and pedal sustain
US3918342A (en) * 1973-09-14 1975-11-11 Keio Giken Kogyo Kabushikikais Monophonic electronic musical instrument of equal tempered scale
US4016792A (en) * 1974-03-04 1977-04-12 Hammond Corporation Monophonic electronic musical instrument
US3948137A (en) * 1974-03-15 1976-04-06 Nippon Gakki Seizo Kabushiki Kaisha Pitch determining voltage signal generating circuit for a voltage controlled type electronic musical instrument
US4065993A (en) * 1974-12-26 1978-01-03 Nippon Gakki Seizo Kabushiki Kaisha Electronic organ with a three-finger chord and one-finger automatic chord playing mode selector
US4064777A (en) * 1975-09-08 1977-12-27 Roland Corporation Circuit for preferentially selecting highest and lowest tones
US4159663A (en) * 1976-10-28 1979-07-03 Nippon Gakki Seizo Kabushiki Kaisha Electronic musical instrument with different types of tone forming systems
US4186637A (en) * 1977-09-22 1980-02-05 Norlin Industries, Inc. Tone generating system for electronic musical instrument

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ZA734526B (en) 1974-06-26
CA993235A (en) 1976-07-20
BR7305346D0 (pt) 1974-09-05
AU5769573A (en) 1975-01-09
GB1404909A (en) 1975-09-03
JPS5620559B2 (zh) 1981-05-14
DE2336425A1 (de) 1974-01-31
IT991252B (it) 1975-07-30
JPS4959626A (zh) 1974-06-10
NL7309761A (zh) 1974-01-21

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Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:HAMMOND CORPORATION;REEL/FRAME:005262/0045

Effective date: 19890920