JPS5837558B2 - electronic musical instruments - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electronic musical instrument that uses two systems of sound source oscillation circuits to form richer performance sounds and also effectively express modulation effects.

In order to improve the sound effect of electronic musical instruments,
A multi-series sound source system or means for adding effects using various modulations is required.

In order to construct the musical tone shape or means of such an electronic musical instrument, not only the sound source circuit with multiple series but also the oscillator circuit for modulation control etc. are complicated, and especially when adding a modulation effect. , the effect addition state is specified by the modulation oscillator, and it is not possible to produce a sufficient musical effect.

This invention has been made in view of the above points, and aims to improve musical tone formation effects including modulation while maintaining a sufficiently simple structure, thereby enriching performance sound performance. The purpose is to provide an electronic musical instrument, which drives two series of voltage-controlled variable frequency oscillators in response to key operations, and supplies the oscillation output of both or one of them as a sound source signal to a musical tone generator or circuit. The output of the other oscillator is selectively used as a modulation signal for adding a modulation effect to musical tones.

An embodiment of the present invention will be described below with reference to the drawings.

Fig. 1 shows its configuration, in which the keyboard circuit 11 generates a pitch signal with a voltage value corresponding to the pitch of the operated key as a key is operated, and a keying signal corresponding to each key depression and key release. do.

The pitch signal from this keyboard circuit 11 is sent to the first VCO 1.
2 (voltage controlled variable frequency oscillator), and also to the second VCO 14 via one fixed terminal of the first switch 13 of the switching type.

A fixed potential signal of +■ is coupled to the other fixed terminal of the first switch 13.

Further, a potential signal from a voltage setting circuit 15 made of a variable resistor or the like is supplied to the second VCO 14 in the form of a reference voltage signal to be combined with the potential signal from the first switch 13. There is.

The first VCO 12 is controlled to oscillate with a voltage corresponding to the pitch of the operating key, and generates a sound source signal with a frequency corresponding to the pitch of the operating key.

Further, when the first switch 13 is in the state shown in the figure, the second VCO 14 is driven to oscillate by the sum of the voltage signal corresponding to the pitch of the operation key and the voltage signal from the voltage setting circuit 15.
The oscillation frequency is changed in accordance with the pitch of the operating key.

The oscillation sound source signal from the first VCO 1 2 is VC
The signal is supplied to F 1 6 (voltage controlled variable filter) to set the timbre shape or the amplitude envelope is set by VCA 17 (voltage controlled variable gain amplifier) to obtain a musical tone signal output. The seventh section constitutes a voltage-controlled musical tone forming circuit.

Envelope waveform signals from envelope generation circuits 18 and 19 are coupled as control signals to the VCF 1 6 and VCA 1 7, respectively.
In step 16, the cutoff frequency is changed, and the tone color is changed in accordance with the envelope waveform signal, thereby forming a musical tone signal rich in musicality.

Further, the amplification gain of the VCA 17 is changed by the envelope waveform signal to set the amplitude envelope of the output musical tone signal.

In this case, the envelope generating circuits 1B and 19 are coupled with the keying signal from the keyboard circuit 11, so that the generated envelope waveform is controlled to rise and decay in response to key operations such as key presses and key releases. Conditions for shaping the waveform, such as its rise and decay, are set by the control circuit 20.

The musical tone signal taken out from the CA 17 is then sent to the modulation circuit 21, for example, subjected to amplitude (AM) modulation to add an effect, amplified appropriately by the amplifier 22, and supplied to the speaker 23.
Make it sound like a performance sound.

The oscillation output signal from the second VCO 14 is sent to the first VCO 1 as a second sound source signal through the first path 25 by the second switch 24 to the VCF 16 constituting the musical tone forming circuit. The signal is combined with the sound source signal from 2 in a certain state.

Further, the second path 2 by the third switch 26
7, the signal is supplied as a modulation signal to the modulation circuit 21.

That is, in the electronic musical instrument constructed as described above, during normal performance, the second switch 24 is turned on and the third switch 26 is opened, and the oscillation signal from the second VCO 14 is transmitted to the first VCO 14. VCF 1 6 via path 25
is supplied as the second sound source signal.

In this case, the second VCO 14 is oscillated by a signal corresponding to the pitch of the operated key from the keyboard circuit 11, and generates a second sound source signal having a pitch corresponding to the pitch of the operated key. However, the overall value of the oscillation frequency is changed by the potential signal from the voltage setting circuit 15, and the overall value of the oscillation frequency is changed by the potential signal from the voltage setting circuit 15.
A sound source signal with a different pitch from the sound source signal from the second V
It comes to be obtained from CO14.

That is, two series of sound source signals are fed to a musical tone forming circuit consisting of a VCF 16, a VCA 17, etc., which is appropriately formed into a tone and envelope-controlled to produce a performance sound, thereby obtaining a performance musical sound with rich timbre characteristics. This is what happens.

In this case, since no modulation signal is applied from the second path 27 by the third switch 26, the modulation circuit 21 is not activated and no modulation effect is added to the musical tone.

Also, the second switch 24 is opened and the third switch 26 is opened.
If the input setting is made, the first VCO 12 is connected to the musical tone forming circuit.
Only the sound source signals from are combined to form one series of sound sources.

For the modulation circuit 21, the second VCO 1
The oscillation signal from 4 is added as a modulation signal, and the musical tone signal is modulated, for example, in amplitude.

In other words, the performance sound is modulated to follow the pitch, and the modulation speed is slow in the low notes and fast in the high notes, effectively expressing a calm state, a bright state, etc. according to the pitch. Become so.

In the above state, the modulation follows the pitch, but if the first switch 13 is switched from the state shown in the figure and a constant voltage +■ is supplied to the second VCO 14, The modulation speed for musical tones becomes constant, and an effect different from that in the above case is expressed.

In the above embodiment, one of the two sound source circuits is used for the modulation signal that adds the modulation effect, but an independent modulation oscillator 28 is further provided as shown in FIG. You can do it like this.

In this case, the third switch 26 is configured as a switching type, and the second
The configuration is such that one of the signal from the VCO 14 and the signal from the oscillator 28 is selected and supplied to the modulation circuit 21.

In this case, if the oscillation signal from the oscillator 28 is used as a control signal for the VCF 16 as shown by the broken line in the figure, not only the amplitude modulation effect by the modulation circuit 21 but also the timbre modulation effect can be applied to the musical tone signal. This allows you to add more richness to the performance sound.

In FIG. 2, the same components as those in FIG. 1 are designated by the same reference numerals, and detailed explanation thereof will be omitted.

In the above embodiment, the modulation circuit 21 was explained as amplitude modulation (AM), but this is also applicable to frequency modulation (FM), phase modulation (
PM), etc. may of course be used.

Further, the modulation position in this signal system is not limited to the output side of the tone forming circuit as in the embodiment, but may be configured to be included in the preceding stage or inside the tone forming circuit.

Furthermore, although the explanation was omitted in the above embodiment, the first switch 13 is selected to be in the state shown in FIGS. 1 and 2 so that the second VCO 14 is driven to oscillate by the pitch signal from the keyboard circuit 11. When this happens, the second route 2
A frequency divider circuit is inserted in 7, and this frequency divider circuit divides the oscillation output of the VCO 14 to a suitable frequency (for example, 5 to 20Hz) to obtain a chorus/tremolo effect, etc., and this frequency divided signal is transmitted to It may also be coupled to the modulation circuit 21 via the switch 26.

In this way, a tremolo effect that follows the pitch can be obtained.

Furthermore, when a state is selected in which the oscillation output of the second CO 14 is used only as a modulation signal for the modulation circuit 21 (that is, the switch 24 is opened and the switch 26 is turned on), the oscillation output of the second CO 14 is coupled to the second VCO 14. A voltage dividing circuit for dividing the voltage of the pitch signal is provided between the keyboard circuit 11 and the switch 13.
The same effect as described above can be obtained even if the oscillation frequency of the CO 14 is lowered by inserting it in conjunction with the opening of the switch 24.

In this case, there are various possible means for lowering the oscillation frequency of the VCO 14 in addition to the above, but their explanation will be omitted.

As described above, according to the present invention, it is possible to obtain rich performance sounds using a two-series sound source with a sufficiently simple configuration, and also to perform additional control of modulation effects based on the state of pitch tracking, making it possible to perform electronic musical instruments. This has a very large effect on improving performance performance.

[Brief explanation of the drawing]

FIG. 1 is a structural diagram illustrating an electronic musical instrument according to one embodiment of the present invention, and FIG. 2 is a structural diagram illustrating another embodiment of the present invention. 11... Keyboard circuit, 12... First V
CO, 13, 24.26... 1st, 2nd, 3rd
switch, 14...second (7) VC0,
1 6・・・・・VCF. 1 7...V
CA, 18, 19...Envelope generation circuit,
20...control circuit, 21...modulation circuit, 25...first path, 27...second
route.

Claims (1)

[Claims] 1. A keyboard circuit that generates a pitch signal with a voltage value corresponding to the pitch of the operated key as a key is operated, and first and second voltages that are driven and controlled in response to the pitch signal from this keyboard circuit. a controlled variable frequency oscillator, a musical tone forming circuit for forming a musical tone from the oscillation signal from the first variable frequency oscillator, a modulation circuit for adding an effect to the musical tone signal of this musical tone shape or circuit, and the second variable frequency oscillator. An electronic musical instrument comprising first and second paths for selectively guiding the output signal from the frequency oscillator to the tone forming circuit as a sound source signal or to the modulation circuit as a modulation signal, respectively.