JPS5919350B2 - electronic musical instruments - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a self-playing electronic musical instrument that uses an up-down counter in common to eliminate unstable pitch when switching from a glissando effect to a portamento effect.

Conventionally, the present applicant has proposed an "automatic glide effect device" as disclosed in Japanese Patent Application Laid-Open No. 52-52624 as a system for automatically playing the glide effect.

In this method, two systems are used to switch between a normal performance circuit and a performance circuit that produces a glissando effect, so the pitch voltage output from the key signal generation circuit fluctuates due to resistance value errors in series-connected resistors. This causes frequency errors and adversely affects the glissand effect. On the other hand, according to Japanese Patent Application No. 53-20532 "Electronic Musical Instrument" proposed by the present applicant, a common up-down counter is used to distinguish between a performance using the Gritsando effect and a normal performance, as described below. By using the same circuit, it has become possible to automatically perform a highly accurate glissando effect with less influence due to resistance error in the key signal generating circuit.

In this case, in the up-down counter, in the glissando effect, the oscillator 4 is operated at a low frequency every semitone from the first key to the second key, whereas in normal performance, the oscillator 4 may be operated at a high frequency. Further, as an application of this, for a continuously changing portamento effect, if the oscillator is operated at a low frequency less than a semitone, for example every 1/4 semitone, a continuous pitch sensation can be obtained. Of course, the speed of the low frequency can be adjusted freely. However, the problem in this case is that when switching from the glissando effect to the portamento effect, the output of the up-down counter, which is less than a semitone corresponding to the portamento effect, changes in various states, resulting in an unstable feeling. SUMMARY OF THE INVENTION An object of the present invention is to provide a self-playing electronic musical instrument that uses an up-down counter in common and can smoothly switch between glissando and portamento effects to provide a stable pitch sensation.

In order to achieve the above object, the electronic musical instrument of the present invention is
In the electronic musical instrument proposed in No. 3-20532, a switching means for switching between a glissando effect that changes the output of an up-down counter every semitone and a portamento effect that changes almost continuously every less than a semitone, and an operation that is linked to the switching means and a control circuit in which the up-down counter outputs all digits in the portamento effect and outputs all digits less than a semitone in the glissando effect, and the switching means controls the output of the up-down counter so that it outputs all digits in the portamento effect and outputs all digits less than a semitone in the glissando effect, and When switching from the effect to the portamento effect, the digit of the output of the up-down counter that is less than a semitone is instantly set.

The present invention will be described in detail below with reference to examples.

FIG. 1 is an explanatory diagram showing the structure of an embodiment of the present invention, in which the structure of the present invention is added to the embodiment of the previously proposed Japanese Patent Application No. 53-20532 "Electronic Musical Instrument".

In the figure, a key switch output 1 of a key signal generating circuit 1 consisting of a group of resistors connected in series and a group of short-circuited key switches is branched into two, and one is input into a key press detection circuit 12 to generate a high level key press signal 2. It is detected and input to the start (S) terminal of the oscillator 4.

The frequency of the oscillator 4 can be manually adjusted continuously from low frequency to high frequency by adjusting the resistor R, and this oscillation output 3 is input to the clock (CL) terminal of the up-down counter 5 to start counting operation. . Therefore, by adjusting the resistor R of the oscillator 4, the oscillation frequency changes continuously from a low frequency to a high frequency, which changes the counting speed of the up-down counter, and as a result, the speed of glissando and portamento can be adjusted. be. FIG. 3 is an explanatory diagram of the operation of the main part of the embodiment, illustrating an example of the operation of the oscillator 4 and the change in the output frequency of the musical waveform forming circuit 10.

Initially, the musical sound waveform forming circuit 10 generates the pitch of the previously pressed key. Here, when the C1 key is pressed, the output 3 of the oscillator 4 automatically changes from the manually set low frequency to a high frequency for a moment, and the up/down counter 5 counts at high speed, so that the pitch changes. It becomes C1 instantly. Thereafter, the output 3 of the oscillator 4 returns to the manually set low frequency. Here, when key C1 is pressed and C2, which has a lower pitch, is pressed, the up-down counter 5 starts to move down, but since there is no change in the key press signal 2, the frequency of the oscillator 4 is Without changing, this speed produces a glissando effect and a portamento effect according to the manually set output frequency of the oscillator 4. When the C2 pitch is reached, the up-down counter 5 stops counting. The output 4 from the up-down counter 5 is sent through the D/A converter 6, and the key switch output 1 is sent to the buffer amplifier 11.
The output signal 6 is inputted to a comparator 8 for comparison with the output 5 passed through the counter, and the output signal 6 is inputted to an up-down (U/D) terminal of an up-down counter 5 to perform up-down control of counting.

Further, both inputs 4 and 5 of these comparators 8 are input to a window comparator 14, and the window comparator 14 is operated so that its output 7 becomes high level when both inputs almost match. The output 7 of this window comparator 14 is converted into an up-down counter 5.
This is connected to the stop (DIS) terminal of the counter to control the stop of the counting operation. As described later in FIG. 2, the output of the up-down counter 5 has an 8-bit configuration of Ql, Q2, Q3 to Q8, for example, where Q1 is in 1/4 semitone units, Q2 is in 1/2 semitone units, and Q3 is in semitone units. If you set the unit as..., the Gritsand effect will change in semitone units, so Q
Since the portamento effect changes continuously in units of 1/4 semitone, Q1 to Q8 are used. Therefore, in the Gritsand effect, the lower two digits are inactive, and in the Portamento effect, all digits are used. The output of the up-down counter 5 is D/A converted by a D/A converter 6, and the output signal 4 is sent to a musical sound waveform forming circuit 10 together with an attack signal @ to be described later and converted into a musical tone. The above configuration is substantially the same as the previously proposed embodiment.

In the present invention, the following configuration is added to this. That is, the match signal from the window comparator 14 is input into the differential waveform forming circuit 21 to create a single pulse, which is passed through the portamento side of the glissando/portamento switch (SW) 22, and is output together with the key press signal as the attack signal @ after the portamento effect. The signal is input to the musical sound waveform forming circuit 10. Further, the output of each semitone from the Q3 output of the up-down counter 5 is inputted to the glissando side of the changeover switch (SW) 22 as an attack signal in the glissando effect. A control circuit 24 is provided for controlling the Ql and Q2 outputs of the up-down counter 5 using a preset enable (PE) terminal in conjunction with the changeover switch (SW) 22. As shown in detail in FIG. 2, the control circuit 24 is a non-short switch 26 in which the lower outputs Ql and Q2 of the up-down counter are shunted through resistors Rl and r2, respectively.
, 27 to the D/A converter 6 manually.

Non-short switch 26 interlocking with changeover switch 22
, 27 becomes open for a moment between the Q1 terminal, Q2 terminal and ground when switching between grit sand and portamento, so the D/
The two inputs of the A converter 6 become electrically unstable, and as a result, the pitch becomes unstable, so the resistors Rl and r2 are connected to the D/A converter 6.
It is necessary to select a resistor with lower impedance than, for example, a step resistor inside the converter 6. The non-short switches 26 and 27, along with the changeover switch 22 and the C non-short switch 25 described later, are used as switches that have a time period in which the two circuits are momentarily opened when switching between the two circuits. In addition, a non-short switch 25 is provided which interlocks with the changeover switch 22, and is momentarily opened when switching between glissando and portamento, and applies a voltage to the preset enable (PE) terminal of the up-down counter 5 to output outputs Ql and Q2. The device is reset and immediately becomes operational.
In this case, the preset terminals PlP2 of the outputs Ql and Q2 are grounded in advance. Furthermore, since the non-short switches 26 and 27 are short-circuited at the positions shown during the portamento effect, all outputs Q1 to Q8 are in the operating state. During the Gritsand effect, the outputs Ql and Q2 are grounded through the resistors Rl and r2, so they are both inactive, and the outputs Q3 to Q8
only is in operation. In the above configuration, when the first key is continuously pressed, the output of the key press detection circuit 12 starts the oscillator 4 which is in a stopped state, sends the oscillation output 3 to the up/down counter 5, and starts operating the D/A converter. 6 to the tone waveform forming circuit 10.

At the same time, a key press signal enters the gate circuit of the musical sound waveform forming circuit 10, and is combined with the output pulse of the monostable multivibrator operated by the attack signal @, and is sent to the voltage controlled oscillator (VCO), voltage controlled filter (CF), A musical tone is output by applying a control signal to an envelope generator (EG) comprising a control amplifier (CA). Next, when portamento is set by the changeover switch (SW) 22, when the first key is pressed and then the second key is pressed, the output of the D/A converter 6 and the buffer amplifier of the second key are switched. The comparator 8 compares the output voltage of the 11 with the output voltage of the 11, and if the level is high, the up/down counter 5 starts counting up. That is, if the first key is pressed at time T1 and the second key is pressed at time T2, up-counting starts at T2, and the portamento effect is performed from time T2 to time T3, and the pitch changes to the first key. From there, it rises smoothly towards the second key. Then, at time T3, the output of the window comparator 14 becomes high level, and this change in signal ◎ causes the differential waveform rectifier circuit 21 to form an attack signal after portamento, which then passes through the changeover switch (SW) 22 to produce a musical tone. The signal is input to the waveform forming circuit 10. At the same time, the output of the window comparator 14 enters the DIS terminal of the up-down counter 5, stopping up-counting. Then, a musical tone with an attack is output. A similar portamento effect occurs when counting down. In the case of the glitsand effect, the output of the up-down counter 5 is output Q3 every semitone.
Q8 connects to the musical sound waveform forming circuit 1 via the D/A converter 6.
Enter 0.

At the same time, the signal is branched from the output Q3 and input as an attack signal to the tone waveform forming circuit 10 via the changeover switch (SW) 22, thereby producing a glissando effect. When the switch 22 from glitsando to portamento is turned to the portamento side, as shown in Figure 2, in grissando, output Q3 is a semitone bit, output Q2 is a 1/2 semitone bit, and output Q
Since 1 is a 1/4 semitone bit, the changeover switch 22
Depending on the timing of the switch from gritsando to portamento, there are four possible states shown in the table below. State 2, 3,
4, each key on the keyboard is spaced at semitone intervals, so it sounds unstable to the ear. In state 1, since Ql and Q2 are O, they match the semitone pitch of each key, giving a normal pitch feeling. Therefore, as shown in FIG. 2, by momentarily setting the PE terminal of the up-down counter to a high level using the non-short switch 25, Ql and Q2 are reset and immediately returned to a low level, thereby eliminating the portamento effect. It is in an operating state.

In the portamento effect of the present invention, the pitch rises smoothly from the first key to the second key, and when the pitch of the second key is reached, the sound is produced at that pitch with an attack, which is different from the conventional portamento effect. It gives a unique effect.

As explained above, according to the present invention, a changeover switch for changing over between the glissando effect and the portamento effect, and a control circuit linked to the changeover means are provided, and the up-down counter is configured to change the up-down counter every less than a semitone corresponding to the portamento effect. The output is rendered inactive during the glissando effect, and momentarily set and returned to the operating state during the portamento effect, thereby providing a stable pitch when switching from the glissando effect to the portamento effect.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing the configuration of an embodiment of the present invention, FIG. 2 is a detailed explanatory diagram of the main part of FIG. 1, and FIG. 3 is an explanatory diagram of the operation of the main part of the embodiment of the invention, In the figure, 1 is a key signal generation circuit;
4 is an oscillator, 5 is an up-down counter, 6 is a D/A converter, 8 is a comparator, 10 is a musical waveform forming circuit, 11 is a buffer amplifier, 12 is a key press detection circuit, 21 is a differential waveform rectifier circuit, 14 is a window Comparator, 22
24 is a control circuit, and 25, 26, and 27 are non-short switches.

Claims (1)

[Claims] 1. A key signal generation circuit that generates a signal corresponding to the pitch of a pressed key, an up-down counter that counts the clock signal input to the clock section and outputs the counted value as an output signal, and the up-down counter. an oscillator that provides a clock signal to the clock section of the key signal generating circuit; a comparator that compares the output signal of the key signal generating circuit with the output signal of the up/down counter to control the counting direction of the up/down counter; and an output of the key signal generating circuit. means for stopping the up-down counter when the signal and the output signal of the up-down counter match, and a musical waveform forming circuit for converting the output signal of the up-down counter into a musical tone of a pitch corresponding to the output signal of the up-down counter. In electronic musical instruments,
A switching means for switching between a glissando effect that changes the output of the up-down counter every semitone and a portamento effect that changes it almost continuously every less than a semitone, and a control circuit interlocked with the switching means, the control In the circuit, the output of the up-down counter is controlled so that all digits are output in the portamento effect, and all digits less than a semitone are output in the gliesando effect, and when the switching means switches from the gliesande effect to the portamento effect, An electronic musical instrument characterized in that digits less than a semitone in the output of an up-down counter are instantaneously reset.