Wind Instrument Sound Producing System For Electronic Musical Instruments

Abstract

The system comprises means to cause signal having clarinet voice to have a predetermined envelope, means to cause a second tone signal having trumpet voice to have a predetermined envelope, means to cause a noise tone signal to have a predetermined envelope, and means to generate a sound simulating that of saxophone voice after the outputs of all of said means are mixed and amplified.

Description

This invention relates to a wind instrument sound producing system for an electronic musical instrument capable of producing a composite sound having an envelope representing the sound of a wind instrument such as, in particular, a saxophone.

When a sound simulating that of a natural musical instrument is to be produced by a conventional electronic musical instrument, a composite sound has been produced in such a manner that it simulates only the formant of the playing sound of a corresponding musical instrument. The sound of a natural wind instrument having its general characteristic in the envelope of sound or, in particular, in such part of the envelope that corresponds to the sound to be produced at the beginning of the play can not be faithfully simulated by an electronic musical instrument. Especially where the characteristic of sound is in the beginning part of sound production as in a wind instrument such as a saxophone, such characteristic in the beginning part of sound production plays an important role in identifying each musical instrument.

An object of this invention is to provide a wind instrument sound producing system for an electronic musical instrument, which faithfully composes the sound of wind instrument, such as, a saxophone.

Another object of this invention is to provide a wind instrument sound producing system for an electronic musical instrument, such as a saxophone, which composes a sound having an envelope in the beginning of sound production, which simulates that of the natural musical instrument.

This invention thus provides a system for producing the sound of a wind instrument, wherein a first tone signal having a clarinet voice, a second tone signal having a trumpet voice, and a third noise tone signal are caused to have predetermined envelopes, and wherein said signals are mixed to generate a sound signal which is supplied to a speaker through a usual amplifier system.

BRIEF EXPLANATION OF THE DRAWINGS

FIG. 1 is a circuit diagram embodying the system in accordance with this invention;

FIGS. 2A to 2C show charts indicating the envelopes of a composite sound to be produced, to explain the function of the system of this invention;

FIG. 3 is a circuit diagram embodying an envelope circuit employed in the system;

FIGS. 4A to 4C are charts showing the variation of voltage of lamps used in a control system in FIG. 3; and

FIG. 5 is a circuit diagram showing a modification of the envelope circuit.

DETAILED DESCRIPTION OF THE INVENTION

The invention will be described in connection with the production of a tone signal simulating the sound of a saxophone. In FIG. 1, the reference numeral 11 represents a tone generator circuit for generating a tone signal which is fed to a keying circuit 13 which is operated and controlled in response to the operation of a keyboard 12 and from which a tone signal corresponding to an operated key is derived. The tone signal is divided into signal components which then are introduced into first and second tone coloring circuits 14 and 15, whereby a signal representing a tone color of clarinet voice is obtained from the first tone coloring circuit 14 and consists of odd harmonics, and a signal representing a tone color of trumpet voice is derived from the second tone coloring circuit 15 and has a formant in range of 1KH.sub.2 to 2KH.sub.2. These two tone signals are respectively supplied to first and second envelope circuits 16 and 17 from which two tone signals each having a regulated tone color and envelope are respectively derived. Namely, from the envelope circuit 16 is derived a signal of a slow rise time and a successive sustenance, namely, of the envelope as shown in FIG. 2A. This signal derived from the envelope circuit 16 simulates clarinet voice which has a tone of stepped pipe or a mellow tone. From the second envelope circuit 17 is similarly derived a signal having the envelope of a rapid rise time and a rapid decay with a weak sustaining tone, as shown in FIG. 2B. This signal derived from the envelope circuit 17 simulates trumpet voice which has a brilliant tone.

In addition to the tone generator circuit 11 is provided a noise generator 18. The signal produced by the noise generator 18 is supplied to a band-pass filter 20 corresponding to an operated key, through a keying circuit 19 controlled similarly by the keyboard 12. The band-pass filter 20 has narrow pass bands about such frequencies of the notes that correspond to the respective keys and converts the signal from the noise generator 18 into a white noise signal having respective pitch sensations, whose envelope is then regulated by a third envelope circuit 21. From the third envelope circuit 21 is thus derived a signal having such an envelope that represents a tone of a rapid rise time and a rapid decay with a successively sustained weak tone, as shown in FIG. 2C. The clarinet signal, trumpet signal and the noise signal respectively passed through the first, second and third envelope circuits 16, 17 and 21 are combined and fed to a third tone coloring circuit 22 to produce a sound signal output simulating the sound of a saxophone. Since the tone coloring circuit 22 is auxiliary, it may be omitted.

In the electronic musical instrument of the arrangement described above, when the keyboard is operated, a noise signal is first raised through the keying circuit 19 and the third envelope circuit, thereby to produce a noise tone simulating a blow of breath which appears in playing on wind instruments. Following this, a trumpet sound is rapidly raised through the second envelope circuit 17. Thus, a combination of the noise signal and the trumpet signal expresses a sound of the initial blowing stage of a saxophone, which includes a sound of breath at initial blowing and a successive loud sound during the initial stage of the play. Thereafter, the clarinet signal obtained through the first envelope circuit 16 is continuously sounded together with the trumpet signal and the noise signal which both are sustained faintly, whereby a tonal effect substantially equivalent to that of the saxophone can be obtained by the operation of the keyboard. In this case, the saxophone effect is more conspicuously expressed owing particularly to the faintly sustained noise tone signal.

FIG. 3 is a circuit diagram illustrating an example of the envelope circuit arrangement in the electronic musical instrument including the construction above described. The first, second and third envelope circuits 16, -7 and 21 are respectively formed mainly of first, second and third photoconductive elements 31, 32 and 33. The clarinet, trumpet and noise tone signals from terminals 34, 35 and 36 connected respectively to the tone coloring circuits 14 and 15 and the band-pass filter 20 in FIG. 1 are combined through a series connection of said photoconductive elements 31, 32 and 33 and are introduced into an amplifier circuit formed, for example, of a transistor 38, via a tone color filter 37 comprising a resistor and a capacitor, said tone color filter 37 and said transistor 38 constituting the third tone coloring circuit 22 of FIG. 1.

The photoconductive elements 31, 32 and 33 are respectively radiated by first, second and third lamps 39, 40 and 41, so that the conductivity of the photoconductive elements 31, 32 and 33 are variably controlled in proportion with the intensity of radiation of the lamps 39, 40 and 41, and hence with the magnitude of the voltage impressed across the both ends of the lamp, thereby regulating the envelope of the signal passing through these photoconductive elements.

Namely, a switch 49 represents make contacts disposed on the keyboard. When the switch 49 is closed, the first lamp 39 is impressed by a voltage of +39 volts through a first time constant setting circuit formed of a T-network consisting of a capacitor 42 and resistors 43 and 44. Similarly, the lamps 40 and 41 are impressed by a voltage of 36 volts, respectively through a second time constant setting circuit consisting of a parallel connected capacitor 45, serially connected resistors 46 and 47 and a capacitor 48 connected in parallel with said resistor 47, and through a third time constant setting circuit consisting of a capacitor 50 connected in parallel with the lamp 41, serially connected resistors 51 and 52 and a capacitor 53 parallel connected with said resistor 52.

The value of each of the capacitors 42 and 45, is 100 .mu.F, and that of each of the capacitors 48, 50 and 53 is 50 .mu.F, and those of the resistors 43, 44, 46, 47, 51 and 52 are 2.5 K.OMEGA., 200 .OMEGA., 5 K.OMEGA., 200 .OMEGA., 200.OMEGA. and 5 K.OMEGA., respectively. With the impression of a voltage of +36 volts as just described, the amount of the voltage impressed across each of the lamp 39, 40 and 41 upon the closing of the switch responsive to the operation of the keyboard is as shown in FIGS. 4A to 4C, in which the voltage characteristics are approximately equal to the envelopes of the respective tone signal components for producing a composite saxophone sound as shown in FIG. 2. The clarinet and trumpet tone signals and the noise tone signal are thus controlled to have predetermined envelopes by causing the lamps 39, 40 and 41 to radiate the photoconductive elements 31, 32 and 33 serially inserted in the signal circuit.

FIG. 5 shows a modification of the envelope circuit, which is capable of accurately obtaining predetermined envelopes from the envelope circuits shown in FIG. 3 without the aid of lamps. The first envelope circuit 16 is formed of a cascade connection of an integrator 60 connected to the switch 61 representing the make contacts and a first envelope regulating circuit 62. The second envelope circuit 17 is formed of a cascade connection of a pulse shaper 63 connected to said switch 61, a monostable multivibrator 64, an integrator 65 and a second envelope regulating circuit 66. The third envelope circuit 21 is formed of a cascade connection of a pulse shaper 63 connected to said switch 61, a monostable multivibrator 67, an integrator 68 and a third envelope regulating circuit 69.

The output voltage of said integrator 60 is supplied to the gate of a field effect transistor 70 constituting a first envelope regulating circuit 62 to cause its gate signal to control the clarinet tone signal supplied from the first tone coloring circuit 4 (shown in FIG. 1) to the drain of the field effect transistor 70 so as to have the envelope as shown in FIG. 2A. The output voltage of said integrator 65 is supplied to the gate of a field effect transistor 71 constituting a second envelope regulating circuit 66 to cause its gate signal to control the trumpet tone signal supplied from the second tone coloring circuit 15 (shown in FIG. 1) to the drain of the field effect transistor 71 so as to have the envelope as shown in FIG. 2B. The output voltage of said integrator 68 is supplied to the gate of a field effect transistor 72 constituting a third envelope regulating circuit 69 to cause its gate signal to control the noise signal supplied from the band-pass filter 20 (shown in FIG. 1) to the drain of the field effect transistor 72 so as to have the envelope as shown in FIG. 2C. Outputs of said envelope regulating circuits 62, 66 and 69 are combined and fed to the third tone coloring circuit 22. From the output terminal of the third tone coloring circuit 22 is obtained the saxophone tone signal simulating the sound of a saxophone and which has such an envelope that is resulted from a mixture of the tone signals having three different envelopes as shown in FIGS. 2A to 2C.

As has been stated according to this invention, a variation in a tone color and a tone envelope which are the characteristics of the sound of a wind instrument, in particular, a saxophone, can be expressed by an electronic musical instrument. Further, a sound representing the initial breathing out, characteristic of the playing sound of this type of musical instrument can be excellently produced. Thus, a musical sound simulating that of a wind instrument, which has heretofore been difficult to produce, can be produced by means of an electronic musical instrument.

Claims

1. A wind instrument sound producing system for an electronic musical instrument comprising means for generating a first tone signal having a clarinet-type tone color, means for generating a second tone signal having a trumpet-type tone color, means for generating a third noise tone signal, a first envelope circuit for controlling said first tone signal to cause said first tone signal to have an envelope having a slow rise time and which is successively sustained, a second envelope circuit for controlling said second tone signal to cause the second tone signal to have an envelope having a moderate rise time and which successively rapidly decays to represent a faintly sustained sound, a third envelope circuit for controlling said third tone signal to cause the third tone signal to have an envelope having a rapid rise time and which rapidly decays to represent a sustained sound weaker than said faintly sustained sound, and an extracting means for converting a sound signal obtained by mixing the outputs from said first, second and third envelope circuits into a musical

2. The system according to claim 1 wherein said first tone signal generating means comprises a tone generating a tone signal, a first keying switch receiving said tone signal and responsive to a keyboard, and a first tone coloring circuit for causing an output signal from said first keying switch to have a clarinet-type sound, said second tone signal generating means comprises a second tone coloring circuit for causing the tone signal generated by said tone generator and supplied thereto through said first keying switch to have a trumpet-type sound, and said third tone signal generating means comprises a noise tone generator for generating a noise tone signal, a second keying switch for receiving said noise tone signal and operated in response to the keyboard, and a band-pass filter to

3. The system according to claim 2 wherein said first envelope circuit comprises a first time constant setting circuit energized by a DC power supply through a switch, a first lamp lit by an output voltage derived from said first time constant setting circuit and which has a waveform of the same pattern as an envelope required in said first envelope circuit, and a first photoconductive element to which said first tone signal derived from said first tone coloring circuit is fed and which is radiated by said first lamp to vary a conductivity in response to the intensity of radiation of said first lamp, said second envelope circuit comprises a second time constant setting circuit energized by a DC power supply through said switch, a second lamp lit by a voltage derived from said second time constant setting circuit and which has a waveform of the same pattern as an envelope required in said second envelope circuit, and a second photoconductive element to which said first tone signal derived from said second tone coloring circuit is fed and which is radiated by said second lamp to vary a conductivity in response to the intensity of radiation of said second lamp, and said third envelope circuit comprises a third time constant setting circuit energized by a DC power supply through said switch, a third lamp lit by a voltage derived from said third time constant setting circuit and which has a waveform of the same pattern as an envelope required in said third envelope circuit, and a third photoconductive element to which said third tone signal derived from said third tone coloring circuit is fed and which is radiated by said third lamp to vary a conductivity in response to the intensity of radiation of

4. The system according to claim 2 wherein said first envelope circuit comprises a cascade connection of a first integrator connected to a switch to represent make contacts and a first envelope regulating circuit including a first field effect transistor having a drain to which said first tone signal is applied from said first tone coloring circuit and a gate to which an output from said first integrator is supplied and controlling the envelope of said first tone signal by the gate signal obtained, said second envelope circuit comprises a cascade connection of a pulse shaper connected to said switch, a first monostable multivibrator, a second integrator and a second envelope regulating circuit including a second field effect transistor having a drain to which said second tone signal is supplied from said second coloring circuit and a gate to which an output from said second integrator is supplied and controlling the envelope of said second tone signal by the gate signal obtained; and said third envelope circuit comprises a cascade connection of said pulse shaper connected to said switch, a second monostable multivibrator, a third integrator and a third envelope regulating circuit including a third field effect transistor having a drain to which said third tone signal is supplied from said band-pass filter and a gate to which an output from said third integrator is supplied and controlling the envelope of said

5. A circuit device comprising a first time constant circuit from which a first signal is derived, said first signal having an envelope which has a slow rise time, reaches a peak point in 500 ms. after the beginning of the signal and later stands at a constant level, a second time constant circuit from which a second signal is derived, said second signal having an envelope which has a moderate rise time, reaches a peak point in 40 ms. after the beginning of the signal, has a moderate decaying time and later stands at a constant level to represent a faintly sustained sound; and a third time constant circuit from which a third signal is derived, said third signal having an envelope which has a rapid rise time reaches a peak point in 20 ms. after the beginning of the signal, has a rapid decaying time and later stands at a constant level to represent a sustained sound weaker than said faintly sustained sound.