JPS6125038Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention uses a first arbitrary voltage _E2 for effect to arbitrarily synthesize or continuously combine the envelope of a so-called percussion effect such as a piano sound or percussion instrument sound with the envelope of a normal musical sound signal. variable limit,
Envelope generation for an electronic musical instrument in which the length of a sustain effect can be arbitrarily varied and added to the envelope obtained by the above-mentioned first effect voltage E ₂ using an arbitrary voltage E ₃ for a second effect. Regarding equipment.

An embodiment of the present invention is shown in FIG. 1 and will be described in detail below.

That is, one side of the key switch K ₁ is connected to the power source E ₁ , and the other side is connected in series with the first capacitor.
C ₁ and the first diode D ₁ to the buffer A ₁ , and the connection point A between the key switch K ₁ and the first capacitor C ₁ and the first capacitor C ₁ and the first diode. The connection point B with D ₁ is connected through a first resistor R ₁ and a second diode D ₂ connected in series, and the first resistor R ₁ and the second diode D ₂ are connected in series.
the first through the third diode D ₃ at the connection point with
Connect an arbitrary voltage E ₂ for the effect of , and connect the second capacitor C ₂ and the second resistor R ₂ in parallel to the connection point of the first diode D ₁ and the buffer A ₁ and the ground level. Connect and further buffer with the first diode D ₁
An arbitrary voltage for the second effect is applied to the connection point G with A ₁ through the third resistor R ₃ and the fourth diode D ₄
It is formed by connecting E ₃ in series.

In the above configuration, if the first voltage E ₂ and the second voltage E ₃ are both at ground level, the first resistor
The connection point between R ₁ and the second diode D ₂ is connected to the ground level via the third diode D ₃ , and the third resistor R ₃ is connected to the ground level via the fourth diode D ₄ . The first capacitor C ₁ , the second resistor R ₂ , and the third resistor R ₃ constitute a differential circuit, so the key switch K ₁ is turned ON as shown in section t ₁ of FIG. 2A. , when turned OFF, the second
Time constant τ of a differentiator circuit as shown in interval t ₁ in Figure B ₁
Since a voltage appears that decays at ₁ and is transmitted through the first diode D ₁ to the connection point G,
The voltage waveform at the connection point G becomes as shown in the section t ₁ ' in FIG. 2 G ₁ , and the voltage waveform at the output V ₀ via the buffer A ₁ is shown in the section t _{1 '} in FIG. 2 G 1 . An envelope voltage waveform appears and the envelope of the percussion effect is obtained.

Next, when the first voltage E ₂ is set to, for example, 1/2 of the voltage of the power supply E ₁ and the key switch K ₁ is turned on with the second voltage E ₃ at the ground level, the first resistor R ₁ and Second
The voltage at the connection point with diode D ₂ becomes approximately 1/2 of the voltage of the power supply E ₁ through the third diode D ₃ , and at a voltage lower than 1/2 of the voltage of the power supply E ₁ , Since the connection point A and the connection point B become conductive through the first resistor _R1 and the second diode _D2 ,
After attenuating with the time constant τ ₁ , the power supply is connected to the connection point B.
A voltage waveform that is constant at 1/2 of E ₁ appears,
It is transmitted to the connection point G via the first diode _D1 . Next, when key switch _K1 is turned OFF, connection point A and connection point B immediately go to the ground level, but
The connection point G does not reach the ground level immediately due to the action of the second capacitor _C2 .
C ₂ , the second resistor R ₂ , and the third resistor R ₃ form a voltage waveform that attenuates with the time constant τ ₂ of the discharge circuit. Therefore, as the key switch _K1 turns ON and OFF _{, a} voltage waveform shown in section _{t2 '} in FIG. An envelope voltage waveform similar to the voltage waveform of G appears.

That is, an envelope is obtained in which the envelopes of the percussion effect and the normal musical tone signal are synthesized.

Next, when the key switch K ₁ is turned on with the first voltage E ₂ set to the same voltage as the power supply E ₁ and the second voltage E ₃ set to the ground level, the first resistor R ₁ and the second
The voltage at the connection point with the diode _D2 becomes almost the same voltage as the power supply _E1 through the third diode _D3 , and the connection point A and the connection point B are connected to the first resistor _R1 and the second diode D. ₂ becomes conductive, so that a voltage approximately equal to that of the power source E ₁ appears at the connection point G via the first diode D ₁ . Next, when the key switch is turned OFF, the voltage at the connection point B immediately goes to the ground level as described above, but due to the action of the second capacitor _C2 , the voltage at the connection point G has the above-mentioned time constant τ ₂
A voltage waveform appears that attenuates at . Therefore, as the key switch _K1 turns ON and OFF, the connection point G is connected to the
A voltage waveform shown in interval t ₃ ′ of G ₁ appears, and the output
An envelope voltage waveform similar to the voltage waveform at the connection point G appears at _V0 via the buffer _A1 , and the envelope of the normal musical tone signal is obtained.

Next, the effect of the second voltage _E3 will be explained in detail below.

In Fig. 1, connection point B and connection point G are the first
Since the connection is unidirectional by _the diode D _{1 of} The circuit is the second resistor
R ₂ , the third resistor R ₃ , the fourth diode D ₄ , and the second voltage E ₃ , the voltage at the connection point G reaches the voltage level of the second voltage E ₃ .
is discharged by the resistor R ₂ , the third resistor R ₃ , and the fourth diode D ₄ , and a voltage waveform that attenuates with the time constant τ ₂ appears at the connection point G.
When the voltage becomes lower than the second voltage _E3 , the third resistor _R3 is disconnected from the discharge circuit by the action of the fourth diode _D4 , and discharge is performed only by the second resistor _R2. Therefore, the time constant τ formed by the second capacitor C ₂ and the second resistor R ₂
A voltage waveform which is attenuated by ₃ appears at the connection _point G, and this voltage waveform is obtained as a sustain effect envelope voltage waveform at the output _V0 via the buffer A1.

In other words, the sustain effect time is equal to the second voltage.
The time constant τ ₂ can be continuously varied from the time constant τ 2 to the time constant τ ₃ by E ₃ .

Similarly, the time constant τ ₁ of the differentiating circuit that forms the envelope time constant of the percussion effect is lower than the voltage level of the second voltage E ₃ between the first capacitor C ₁ and the second resistor R. The time constant formed by ₂ and τ changes to ₄ .

That is, the time of the percussion effect is also
The time constant τ 1 can be continuously varied from the time constant τ ₁ to the time constant τ ₄ by the second voltage E ₃ , and an example of the waveform of the envelope voltage is shown in FIG. 2 G ₂ .

In addition, the example shown by the dotted line in FIG. 2 _G2 is when the second voltage _E3 is 1/2 the voltage of the power source _E1 ,
The solid line part is when the voltage is the same as that of the power supply _E1 .

Further, the buffer A ₁ is a circuit connected to the output V ₀ to prevent interference between the buffer A 1 and the envelope generator of the present invention.

As explained above, in the present invention, the envelope of _the percussion effect and the envelope of the normal musical tone signal can be arbitrarily synthesized or continuously varied by the arbitrary voltage E2 for the first effect, and The length of the sustain effect can be arbitrarily varied and added to the arbitrarily obtained envelope using the voltage _E3 .

[Brief explanation of the drawing]

Figure 1 is a circuit diagram showing one embodiment of the present invention;
The figure is a waveform diagram showing the operation. In the drawing, E ₁ is the power supply, E ₂ and E ₃ are the effect voltages, and K ₁
is a key switch, R ₁ , R ₂ , R ₃ are resistors, C ₁ , C ₂ are capacitors, D ₁ , D ₂ , D ₃ , D ₄ are diodes, and A ₁ is a buffer.

Claims (1)

[Scope of utility model registration request] One end of the key switch K ₁ is connected to the power supply E ₁ , and the other end is connected to the buffer A ₁ via a first capacitor C ₁ and a first diode D ₁ connected in series _. A first resistor _R1 and a second diode D2 are connected in series between _{the connection point with the first capacitor C1 and the connection point between the first capacitor C1 and the} first diode _D1. A third resistor is connected to the connection point of the first resistor R ₁ and the second diode D ₂ .
Connect any voltage E ₂ for the first effect through the diode D ₃ of the buffer with the first diode D ₁
A second capacitor C _{2 and} a second resistor R ₂ are connected in parallel between the connection point with A 1 and the ground level, and a third resistor R ₃ and a fourth diode D ₄ are connected in parallel. An envelope generator for an electronic musical instrument, in which an arbitrary voltage _E3 for a second effect is connected in series.