US3260784A - Electronic musical instrument having one or more keyboards - Google Patents

Electronic musical instrument having one or more keyboards Download PDF

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Publication number
US3260784A
US3260784A US409331A US40933164A US3260784A US 3260784 A US3260784 A US 3260784A US 409331 A US409331 A US 409331A US 40933164 A US40933164 A US 40933164A US 3260784 A US3260784 A US 3260784A
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United States
Prior art keywords
frequency
oscillator
keys
tunable
oscillators
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Expired - Lifetime
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US409331A
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English (en)
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Wolfgang J Wehrmann
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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
    • G10H1/02—Means for controlling the tone frequencies, e.g. attack or decay; Means for producing special musical effects, e.g. vibratos or glissandos
    • 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
    • Y10S84/01—Plural speakers
    • 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
    • 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
    • Y10S84/20—Monophonic

Definitions

  • the present invention relates to an electronic musical instrument having one or more keyboards which permits a duophonic playing on each playing manual in such a manner that upon depression of a plurality of keys of one manual the lowest of the depressed keys de-fines one musical voice and the highest of the depressed keys defines the other musical voice.
  • a known method for producing simultaneously two tones on a keyboard-operated instrument is to use a serial mechanism of contacts so that only the lowest and the highest key of a plurality of depressed keys can work.
  • a number of serial changeover contacts is needed equal to the number of keys in the keyboard.
  • the contact banks become very bulky and considerable practical difficulties are encountered in carrying this method into practice.
  • An object of this invention is to achieve the effect of duophonic playing in a new and very profitable manner with respect to prior art, so that for both musical voices of one common manual only relatively low impedances of one kind, e.g., small inductances for both voices, have to be tuned.
  • Another object of the invention is to provide a tone generating circuit by which an exact musical transposition of all tones corresponding to the keys of one manual may be obtained by variation of only a few frequency determinant elements.
  • an electronic musical instrument comprising in combination per playing manual at least three oscillators, two of said oscillators being 'tunable in steps by means of said keys, two modulators or mixers each fed by one tunable and one fixed oscillator and followed by a low pass or band pass filter to obtain the differential mixing frequencies, the variable frequency of one tunable oscillator being lower than the constant frequency of the respective fixed oscillator and the variable frequency of the other tunable oscillator being higher than the constant frequency of the respective fixed oscillator, the frequencies of the tunable oscillators being varied by switching similar serially connected frequency determinant elements in both oscillators, the switching contacts of said keys being so connected in circuit that upon depression of a plurality of keys the tunable oscillator, the frequency of which is lower than the frequency of the fixed oscillator, is being tuned to its respective highest frequency by the lowest depressed key, the tunable oscillator, the frequency of which is higher than the frequency of the fixed oscillator, is being tuned to its respective highest frequency by
  • the respective constant frequency may be the same for both voices, in this case there are only three oscillators for each keyboard needed, otherwise four. By deriving one constant frequency from the other by dividing, multiplying and mixing there are also only three oscillators needed but more modulators and low pass or band pass filters.
  • the duophonic playing may be extended by -multiplying the circuits for duophonic playing, and all switchable frequency determinant elements are switched simultaneously by the keys of one keyboard. By extending the duophonic playing you can simulate an effect like on the organ by records.
  • the drawing shows oscillators 10, 11 and 12, modulators or mixers 27 and 28 with respective low-pass filters 29 and 30, and a swelling unit 43.
  • Oscillator 12 generating aconstant frequency consists of the transistor 1, an oscillating circuit with the coil 2 and the capacitors 3, 4 and 5.
  • the stability of working of the transistor is obtained, as usually, by an emitter resistance 6 and a base-voltagedivider consisting of the resistors 7 and 8.
  • the capacitor 9 between the base and the ground is la short circuit.
  • the oscillating voltage is obtained at the emitter.
  • the circuit diagrams for the oscillators 10 and 11 for the variable frequencies are quite similar. The variable frequencies are switched by contacts actuated by the keys. Some of the contacts (13 up to 18) are depicted.
  • the inductances of the oscillating circuits of the oscillators 10 and 11 consist of serial coils 19, 20, 21, 22 and 23, 24, 25, 26 which are connected by the associated contacts with the negative pole of the battery, if you press the respective keys.
  • the circuit diagram shows the switching contacts of said keys being so connected in circuit that upon depression of a plurality of keys the tunable oscillators are turned to their respective highest frequencies by the lowest and the highest depressed key.
  • the frequencies of the oscillators 10 and 11 or 11 and 12, respectively, are mixed in the modulators 27 and 28, respectively, and at the output of the low-pass filters ,29 and 30, respectively, the differential frequency originates from the mixture product.
  • the frequency of the oscillator 10 is always lower, the frequency of the Oscillator 11 always higher than the frequency of the oscillator 12, therefore the lowest differential frequency, which corresponds to the pressed keys, originates at the output of the low-pass filter 29 and the highest differential frequency, which corresponds to the pressed keys, originates at the output of the low-pass filter 30.
  • the ,frequencies of the oscillators 10, 11 and 12 may be varied by the capacitors 31, 32 and 5 in the same ratio, so that any transposition of the mixture frequencies can be obtained.
  • the inductances 20, 21, 22, 24, 25, 26 are so small, that they can be coils with ferromagnetic cores, therefore they are small in size, cheap and very easy and exactly tunable.
  • the base voltage divider of the transistor of each tunable oscillator has an adjustable resistor by which frequency variation of said tunable oscillators due to kvariations of the supply voltage may be conformed to the frequency variation of the fixed oscillator due to said variation of the supply voltage, so that dependence of the differential mixing frequencies on the supply voltage is minimized.
  • the modulators 27 and 28 work quite analogously, therefore only modulator ifi 27 will be described.
  • the modulator or mixer consists of two cascaded transistors, one transistor (35) with grounded emitter, the other one (36) with grounded collector, the collector of the transistor 3S being D.C.- coupled to the emitter of the transistor 36.
  • the base of the transistor 35 is coupled with the fixed oscillator 12 over the relatively low resistor 3S, and the base of the transistor 36 is coupled with the tunable oscillator over the relatively high resistor 37, the ratio between said relatively high resistor 37 and -said relatively low resistor 38 being from five to twenty.
  • the differential mixing frequency is picked up from the connecting point 39 of the collector of said first-named transistor and the emitter of said second-named transistor.
  • the following low-pass filter 29 avoids unwished frequencies.
  • the circuit diagram shows also an embodiment of the swelling unit.
  • the oscillator ttl produces a constant frequency, which is coupled in the resonant circuit 41 over a resistor 47.
  • the resonant circuit 41 has a .coil 46.
  • the inductance of this coil can be varied by shifting its ferrite core.
  • the devices 41 (resonant circuit), 42, (rectifying circuit) and 44 (gate circuit) can exist for each key and voice or for all keys common but for each voice separate.
  • the ferrite core 46 can be coupled therefore with one or all keys of a keyboard and is shifted by pressing a key. By pressing a key the resonant circuit 41 gets in or out of tune to the frequency of the oscillator 40, so that the A.C. voltage amplitude at the gate circuit 42 is varied. In the same manner the D.C.
  • the device 43 for swelling has a gate circuit (44 or 45, respectively) for each voice, and the first voice, which comes from the low-pass filter 29 passes the gate 44, the second voice from the filter passes the gate 45.
  • each voice is audible or can be stored over an own sound and volume control (55, 57, 56, 58). It is also possible to use common sound and volume control for both voices.
  • An electronic musical instrument having one or more keyboards which permits a duophonic playing on each playing manual in such a manner, that upon depression of a plurality of keys of one manual the lowest of the depressed keys defines on musical voice and the highest of the depressed keys defines the other musical voice, comprising in combination per playing manual at least three oscillators, two of said oscillators being tunable in steps by means of said keys, two modulators or mixers each fed by one tunable and one fixed oscillator and followed by a low-pass or band-pass filter to obtain the differential mixing frequencies, the variable frequency of one tunable oscillator being lower than the constant frequency of the respective fixed oscillator and the variable frequency of the other tunable Oscillator being higher than the constant frequency of the respective fixed oscillator, the frequencies of the tunable oscillators being varied by switching similar serially connected frequency determinant elements in both oscillators, the switching contacts of said keys being so connected in circuit that upon depression of a plurality of keys the tunable oscillator, the frequency of which is lower
  • An electronic musical instrument having one or more keyboards which permits a duophonic playing on each playing manual in such a manner, that upon depression of a plurality of keys of one manual the lowest of the depressed keys defines one musical voice and the highest of the depressed keys defines the other musical voice, comprising in combination per playing manual at least three oscillators, two of said oscillators being tunable in steps by means of said keys, two modulators or mixers each fed by one tunable and one fixed oscillator and followed by a low-pass or band-pass filter to obtain the differential mixing frequencies, the variable frequency of one tunable oscillator :being lower than the constant frequency of the respective fixed oscillator and the variable frequency of the other tunable o-scillator being higher than the constant frequency of the respective fixed oscillator, the frequencies of the tunable oscillators being varied by switching serially connected inductances in both oscillators, the switching contacts of said keys being so connected in circuit that upon depression of a plurality of keys the tunable oscillator, the frequency of
  • An electronic musical instrument having one or ⁇ more keyboards which permits
  • An electronic musical instrument having one or more keyboards which permits ra duophonic playing on each playing manual in such a manner, that upon depression of a plurality of keys of one manual the llowest of the depressed keys defines one musical voice and the -highest of the depressed keys defines the other musical voice, comprising in combination per playing manual at lleast three oscillators, two of said oscillators being tuniable in ⁇ steps by means of said keys, two modulators or mixers each fed by one tunable 'and Ione fixed oscillator and followed by a low-pass or band-pass filter to obtain the differential mixing frequencies, the variable frequency of one tunable oscillator being Ilower than the constant frequency of the respective fixed oscillator and the variable frequency of the other tunable oscillator being higher thlan the constant frequency of the respective fixed oscillator, the frequencies of the tunable oscillators being varied by switching similar serially connected frequency determinant elements in both oscillators, the switching contacts of said keys being so connected in circuit that upon depression o'f
  • An electronic musical instrument having one or more keyboards which permits a duophonic playing on each playing manual in such a manner, that upon depression of a plurality of keys of one manual the lowest of the depressed keys defines lone musical voice and the highest of the depressed keys defines the other musical voice, comprising in combination per playing manual at least three oscillators, two o-f said oscillators being tunable in steps by means of said keys, two modulators or mixers each fed by one tunable and lone fixed oscillator and followed by a low-pass or band-pass filter to Iobtain the differential mixing frequencies, the variable frequency of one tunable oscillator being lower than the oonstant frequency of the respective fixed oscillator and variable frequency of the Iother tunable oscillator being higher than the constant frequency of the respective fixed oscillator, the frequencies of the tunable oscillators being varied ⁇ by switching similar serially connected frequency determinant elements in both oscillators, the switching contacts of said keys being so connected in circuit that upon depression of a plurality
  • each modulator or mixer consisting of two cascaded transistors, one transistor with grounded emitter, the other yone with grounded collector, the collector of said first-named transistor bein-g D.C.coupled to the emitter of said secondnamed transistor, the blase of said first-named transistor being coupled with the fixed oscillator over a relatively low resistance, and the base of said second-named transistor being coupled with the tunable oscillator over a relatively high resistance, the ratio between said relativeL ly high resistance Iand said relatively low
  • An electronic musical instrument having one or more keyboards which permits .a duo-phonic playing on each playing manual in such a manner, that upon depression of a plurality of keys of one manual the lowest of the depressed keys defines one musical voice and the highest of the depressed keys defines the other musical voice, comprising in combination per playing manual .at least three oscillators, two of said oscillators being tunable in steps by ⁇ means of said keys, two modulators or mixers each fed by one tunable and one fixed oscillator and followed bya low-pass or band-pass filter to obtain the differential mixing frequencies, the variable frequency of one tunable oscillator being lower than the constant frequency of the respective fixed oscillator and the variable frequency of the other tunable oscillator being higher than the constant frequency of the respective fixed oscillator, the frequencies of the tunable oscillators being varied by switching similar serially connected frequency determinant elements in both oscillators, the switching contacts of said keys being so connected in circuit that upon depression of a plurality of keys the tunable oscillator, the
  • An electronic musical instrument having one or more keyboards which permits a duophonic playing on each playing manual in such a manner, that upon depression of a plurality of keys of one manual the lowest of the depressed keys defines one musical voice and the highest of the depressed keys defines the other musical voice, comprising in combination per playing manual at least three oscillators, two of said oscillators being tunable in steps by means of said keys, two modulators or mixers each fed by one tunable and one fixed oscillator and followed by a low-pass or band-pass filter to obtain the differential mixing frequencies, the variable frequency of one tunable oscillator being lower than the constant frequency of the respective fixed oscillator and the variable frequency of the other tunable oscillator being higher than the constant frequency of the respective fixed oscillator, the frequencies of the tunable oscillators being varied by switching similar serially connected frequency determinant elements in both oscillators, the switching contacts of said keys being so connected in circuit that upon depression of a plurality of keys the tunable oscillator, the frequency of which is lower than the
  • An electronic musical instrument having one or more keyboards which permits aduophonic playing on each playing manual in such a manner, that upon depression of a plurality of keys of one manual the lowest of the depressed keys defines one musical ⁇ voice and the highest of the depressed keys defines the other musical Voice, comprising in combination per playing manual at least three oscillators, two of said oscillators being tunable in steps lby means of said keys, two modulators or mixers each fed by one tunable and one fixed oscillator and followed by a low-pass or band-pass filter to obtain the differential mixing frequencies, the variable frequency of one tunable oscillator being lower than the constant frequency of the respective fixed oscillator and the variable frequency of the other tunable oscillator being higher than the constant frequency of the respective fixed oscillator, the frequencies of the tunable oscillators being varied by switching simi-lar serially connected frequency determinant elements in both oscillators, the switching contacts of said keys being so connected in circuit that upon depression of a plurality of keys the tunable oscillator
  • An electronic musical instrument comprising in combination per playing manual at least three transistorized oscillators, two of said oscillators being tunable in steps by means of said keys, two modulators or mixers each fed by one tunable and one fixed oscillator and followed by a low-pass or band-pass filter to obtain the differential mixing frequencies, the variable frequency of one tunable oscillator being lower than the constant frequency of the respective fixed oscillator and the variable frequency of the other tunable oscillator being higher than the constant frequency of the respective fixed oscilator, the frequencies of the tunable oscillators being varied by switching similar serially connected frequency determinant elements in both oscillators, the switching contacts of said keys being so connected in circuit that upon depression of a plurality of keys the tunable oscillator, the frequency of which is lower than the frequency of the fixed oscillator, is being tuned to its highest frequency by the lowest depressed key, the tunable oscillator, the frequency of which is higher than the frequency of the fixed oscillator, is being tuned to its respective highest frequency by the highest depressed key,
  • An electronic musical instrument having one or more keyboards which permits a duophonic playing on each playing manual in such a manner, that upon depression of a plurality of keys of one manual the lowest of the depressed keys defines one musical voice and the highest of the depressed keys defines the other musical voice, comprising in combination per playing manual at least three oscillators, two of said oscillators being tunable in steps by means of said keys, two modulators or mixers each fed by one tunable and one fixed oscillator and followed by a low-pass or band-pass filter to obtain the differential mixing frequencies, the variable frequency of one tunable oscillator being lower than the constant frequency of the respective fixed oscillator and the variable frequency of the other tunable oscillator being higher than the constant frequency of the respective fixed oscillator, the frequencies of the tunable oscillators being varied by switching similar serially connected frequency determinant elements in both oscillators, the switching contacts of said keys being so connected in circuit that upon depression of a plurality of keys the tunable oscillator, the frequency of which is lower than the
  • An electronic musical instrument having one or more keyboards which permits a duophonic playing on each playing manual in such a manner, that upon depression of a plurality of keys of one manual the lowest of the depressed keys defines one musical voice and the highest of the depressed keys defines the other musical voice, comprising in combination per playing manual at least three oscillators, two of said oscillators being tunable in steps by means of said keys, two modulators or mixers each fed by one tunable and one fixed oscillator and followed by a low-pass or band-pass filter to obtain the differential mixing frequencies, the variable frequency of one tunable oscillator being lower than the constant frequency of the respective fixed oscillator 4and the variable frequency of the other tunable oscillator being higher than the constant frequency of the respective fixed oscillator, the frequencies of the tunable oscillators being varied by switching similar serially connected frequency determinant elements in both oscillators, the switching contacts of said keys being so connected in circuit that upon depression of a plurality of keys the tunable oscillator, the frequency of which is lower than

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  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Acoustics & Sound (AREA)
  • Multimedia (AREA)
  • Electrophonic Musical Instruments (AREA)
  • Inductance-Capacitance Distribution Constants And Capacitance-Resistance Oscillators (AREA)
  • Input From Keyboards Or The Like (AREA)
US409331A 1963-11-07 1964-11-05 Electronic musical instrument having one or more keyboards Expired - Lifetime US3260784A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
AT889363A AT240144B (de) 1963-11-07 1963-11-07 Elektronisches Tasteninstrument

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US3260784A true US3260784A (en) 1966-07-12

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US409331A Expired - Lifetime US3260784A (en) 1963-11-07 1964-11-05 Electronic musical instrument having one or more keyboards

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Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3558794A (en) * 1965-07-01 1971-01-26 Baldwin Co D H Bass register keying system
US3560628A (en) * 1967-06-30 1971-02-02 Warwick Electronics Inc Multi-channel key switch circuit
US3643000A (en) * 1969-03-12 1972-02-15 Wurlitzer Co Stereophonic electronic piano
US3711618A (en) * 1971-02-22 1973-01-16 A Freeman Automatic harmony apparatus
US3717715A (en) * 1970-10-23 1973-02-20 Philips Corp Electronic musical instrument provided with variable coupling of the keyboards
US3764723A (en) * 1971-03-16 1973-10-09 Nippon Musical Instruments Mfg Voltage-controlled single tone selector for use in electronic musical instrument
US3766305A (en) * 1972-07-17 1973-10-16 Hammond Corp D.c. keyed high low select preference system for polyphonic electrical musical instruments
US3968716A (en) * 1971-06-01 1976-07-13 Melville Clark, Jr. Musical instrument with means for scanning keys
US4227785A (en) * 1979-04-30 1980-10-14 Herbert Henry J Light image translator

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
None *

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3558794A (en) * 1965-07-01 1971-01-26 Baldwin Co D H Bass register keying system
US3560628A (en) * 1967-06-30 1971-02-02 Warwick Electronics Inc Multi-channel key switch circuit
US3643000A (en) * 1969-03-12 1972-02-15 Wurlitzer Co Stereophonic electronic piano
US3717715A (en) * 1970-10-23 1973-02-20 Philips Corp Electronic musical instrument provided with variable coupling of the keyboards
US3711618A (en) * 1971-02-22 1973-01-16 A Freeman Automatic harmony apparatus
US3764723A (en) * 1971-03-16 1973-10-09 Nippon Musical Instruments Mfg Voltage-controlled single tone selector for use in electronic musical instrument
US3968716A (en) * 1971-06-01 1976-07-13 Melville Clark, Jr. Musical instrument with means for scanning keys
US3766305A (en) * 1972-07-17 1973-10-16 Hammond Corp D.c. keyed high low select preference system for polyphonic electrical musical instruments
US4227785A (en) * 1979-04-30 1980-10-14 Herbert Henry J Light image translator

Also Published As

Publication number Publication date
DE1447437B2 (de) 1974-04-11
AT240144B (de) 1965-05-10
DE1447437C3 (de) 1974-11-07
DE1447437A1 (de) 1969-03-13

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