JPS5939752Y2 - musical tone control circuit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to a musical tone control circuit used as a gate so that sustained tones and decayed tones have an audibly balanced volume feel.

In the chord gate circuits of auto basses, chorded electronic organs, etc., the chord performance sound has a sustained sound envelope whose level is constant from the start, and the chord performance sound has a decay sound envelope that decays with a time constant after rising. The bottom of the tank is sealed so that it can be taken out.

FIG. 1 shows an example of a conventionally used chord gate circuit.The sound source signal that becomes the chord performance sound is taken out through a gate circuit G, and this gate circuit G is connected to a changeover switch. gated with an envelope signal coupled via S.

Then, a switch S is connected to one fixed terminal a of the changeover switch S.

The signal from the sustained sound envelope that maintains its rising level after the input of the signal is combined, and this sustained sound envelope signal is further coupled to a differentiation and time constant circuit consisting of a capacitor, a resistor, and a diode, etc., to produce an attenuated sound. It converts it into an envelope signal and leads it to the other fixed terminal of the switch S.

That is, by turning on the switch S to the terminal a or b side, the gate circuit G is gate-controlled with a sustained sound envelope or a damped sound envelope, so that a chord playing sound with a predetermined envelope can be obtained.

According to such a code gate circuit, it is possible to selectively obtain both a sustained tone and a decayed tone with one gate circuit G, but with such a means, it is possible to obtain both a sustained tone and a decayed tone. The peak level of

However, in the case of a musical tone with a decaying sound envelope, even if the peak level of the sustainer is the same as that of the sustainer, the level at which the average sense of volume is obtained does not match that of the sustainer, and is in a very small state.

In other words, in the case of an attenuated sound envelope, the perceived volume is smaller than that of a sustained sound, and the perceptual balance between the sustained sound and the attenuated sound is very poor, making it difficult to effectively express chord performances, etc. It is something that becomes separated.

This idea was created in consideration of the above points, and both sustained sounds and decayed sounds are expressed as musical sounds in an audibly well-balanced state, and chord performances etc. are expressed effectively. The present invention is intended to provide a musical tone control circuit in which gate circuits for sustained tones and attenuated tones are provided in parallel, and the signal system of the gate circuit for sustained tones is set to attenuate.

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

Figure 2 shows its basic configuration.
The sound source signal for chord performance coupled to is supplied in parallel to the first and second gate circuits Gl, G2, and the signals taken out from the gate circuits Gl, G2 are sent to the output terminal Ou.
t and leads to a sound generation circuit having a speaker and the like.

The first and second gate circuits Gl and G2 are gate-controlled by signals of a sustained tone envelope and a decayed tone envelope, respectively.

FIG. 3 shows this in more detail. Gate circuits Gl and G2 are provided in parallel for the human input signal ei from the sound source circuit, and gate circuits G1 and G2 are provided in parallel to form a load resistance circuit for the gate circuit G2. A circuit G3 is provided.

Then, this gate circuit G1°G2. G3 is composed of field effect transistors (FETs) of the same channel, and the gate circuit G1 is given a sustained sound envelope signal as a gate signal, the gate circuit G2 is given a damped sound envelope signal as a gate signal, and the gate circuit G2 is given a damped sound envelope signal as a gate signal. G3
A signal of an attenuated sound envelope having a phase opposite to that of the gate circuit G2 is supplied to the gate circuit G2 as a gate signal.

Then, a resistor R1 is connected in series with the gate circuit G1 to output e.

A resistor R2 is connected to short-circuit the gate circuit G2, a series resistor R3 is connected to the gate circuit G2, a ground resistor R4 is connected, a large resistor R5 is connected to short-circuit the gate circuit, and a series resistor R6 is connected to the gate circuit G3.

Here, gate circuits 61 to G for envelope signals
Looking at the states of the respective resistance values R(Gl) to R(G3) of 3, in the gate circuit G1, the resistance value R(Gl) is substantially infinite in the absence of the envelope signal. Further, in a state where an envelope signal exists, it is set to approximately zero.

In addition, in the gate circuit G2, the resistance value R (G2) becomes zero at the rise of the attenuated sound envelope, changes to approach infinity with the passage of time, and furthermore, the resistance value R (G2) of the gate circuit G3 becomes zero. R (G3) is the above gate circuit G2
The change in resistance value R(G2) is reversed.

In the circuit of FIG. 3 in which such gate circuits 01 to G3 are controlled by the connecting tone or the decaying tone envelope, assuming that only the entire sustained tone envelope is given, the resistance values R (Gl), R (G3) becomes zero, and R(G
2) becomes infinite.

Therefore, in this circuit, the resistor R1 is connected in parallel to the series circuit of the resistors R3 and R5, and the resistor R6 is also connected.

Here, if rR5>RIJ, the resistor R2 has a resistor R
The state is such that current flows only through path 1,
The circuit essentially includes only resistors R1 and R2.

Therefore, the output signal in such a state is e.

If it is set to 1, then it becomes.

In addition, when only the attenuation sound envelope is given, the resistance value R (G1) is set to infinity, and
The resistance value R(G2) changes from zero to infinity, and the resistance value R(G2)
3) will change when this is reversed.

Therefore, the circuit of FIG. 3 has a resistor R(
G2) are connected in parallel, and the resistor R (G3) is connected in series with the resistor R6, and the level 2 at point A is as follows.

Here, since the resistor R5 is very large, it can be ignored, and the circuit after point A in Figure 3 is essentially a circuit of resistors R (G2) and R2, so at that time output signal e.

2 becomes.

In this state, at the peak level of the attenuated sound envelope, that is, at the time of rise, the resistance R (G2
) is in the zero state, so the output at this time is e.

2 becomes the following state from the above equation (2). Output signals e of the sustaining sound envelope and the decaying sound envelope obtained in this way.

1 and e.

Comparing the two, we get the following: Here, rR4
>R3”, rR5>R3”, “R4//R(G3
)+R5>R3J, then.

Therefore, the above equation (3) is e02yoel becomes.

On the other hand, the resistances R1 and R2 have approximately the same value, and -
If not “R2)R1”, then “eo” in (1) above
l < ei J.

For example, if "R1=R2J, eo1=0.5ei becomes.

Therefore, the output e when given the attenuated sound envelope.

2 is the output e when a sustained sound envelope is given.

This is a state in which the peak value is larger than 1.

In the circuit shown in FIG. 3, the resistance value R5 is set to a sufficiently large value, and the values of each resistor are set so as to satisfy the following relationship.

In the above embodiment, the chord playing circuit was described, but
It is not limited to this.

As described above, according to the invention, it is possible to obtain sustained and decaying performance sounds in a well-balanced state, especially audibly balanced, and is particularly effective when used for auto bass, auto chord, etc. It is true.

[Brief explanation of the drawing]

FIG. 1 is a diagram illustrating a conventional code gate circuit, FIG. 2 is a diagram illustrating a musical tone control circuit according to an embodiment of the invention, and FIG. 3 is a diagram illustrating a concrete example of the above circuit. Gl, G2. G3...Gate circuit (FET),
R1-R6...Resistance.

Claims (1)

[Scope of utility model registration request] First and second gate circuits for manually inputting a sound source signal are provided in parallel, and the first gate circuit is controlled by a sustained sound envelope, and the second gate circuit is controlled by a damped sound envelope, respectively. Set,
The output sound source signal of a sustained sound or a decaying sound envelope is selectively extracted from one of the first and second gate circuits, so that the perceptual volume balance of the sustained sound and the decayed sound is balanced. A musical tone control circuit characterized in that the signal path of the first gate circuit is set so that the amount of signal attenuation is greater than that of the signal path of the second gate circuit.