JPS636785Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a musical tone signal control device for an electronic or electric musical instrument.

Conventionally, so-called phase tremolo is known in which a musical tone signal is amplitude-modulated using two low-frequency signals whose phases differ by 180 degrees from each other, and these are emitted from separate speakers.

FIG. 1 is a block diagram of a conventional tone signal control device for phase tremolo. IN in the figure is a musical tone signal input terminal, and this musical tone signal input terminal
As shown in Figure 2A, IN is a musical sound signal derived from a sound source oscillator by a key switch in the case of an electronic musical instrument (in the case of an electric musical instrument, for example, an electric piano, the vibration of the strings or vibrating piece is electrically transmitted). A musical tone signal that picks up suddenly and quickly decays is given. This musical tone signal is guided to a first amplitude modulation circuit 11 and a second amplitude modulation circuit 12. As shown in FIG. 2B, the output signal of the low frequency oscillation circuit 3 is connected to the first amplitude modulation circuit 11 via the variable resistor VR.
1. A control signal is given as a control signal via the tremolo switch S1, and the musical tone signal is amplitude-modulated as shown in FIG. 2D.
VR3 is applied to the first sound emitting device 6 including an amplifier and a speaker via the first output terminal CH1 of this device. On the other hand, the second amplitude modulation circuit 12 has a second
As shown in Figure C, the output signal of the low frequency oscillation circuit 3 is applied as a control signal with a phase shift of 180 degrees via a variable resistor VR1, an inverter 4, and a tremolo switch S2, and a musical tone signal is generated as shown in Figure 2E. Amplitude modulation, second preamplifier 22, variable resistor
VR4 is applied to the second sound emitting device 7 including an amplifier and a speaker via the second output terminal CH2 of this device. Therefore, the first and second sound emitting devices 6,
For example, if 7 is placed on the left and right sides of a musical instrument, it is possible to obtain a phase tremolo that is swung left and right.

In the figure, VR1 is a variable resistor that adjusts the depth of amplitude modulation, and VR2 is a low frequency oscillation circuit 3.
This is a variable resistor for variable frequency. In addition, in the interlocking switches S ₁ and S ₂ , when the movable contact a is in contact with the fixed contact b, a musical tone with tremolo added is obtained, and when the movable contact a is in contact with the fixed contact c, the first and second A required constant voltage V is applied to the amplitude modulation circuits 11 and 12 to obtain a musical tone without tremolo.

The conventional musical tone signal control device requires two amplitude modulation circuits as described above, and also requires two sets of tremolo switches, making it quite expensive.

This invention simplifies the circuit of the conventional device described above and provides an inexpensive device, and it differs between a low frequency oscillation circuit and an amplitude modulation circuit that performs amplitude modulation control of a musical tone signal according to the output signal of the oscillation circuit. a dynamic amplifier, the musical tone signal is guided to one input of the differential amplifier and the input of the amplitude modulation circuit, the output of the differential amplifier is guided to the first sound emitting device, and the amplitude modulation circuit The output of the differential amplifier is guided to the other input of the differential amplifier and also to the second sound emitting device.

FIG. 3 is a block diagram of an embodiment of this invention.
As shown in FIG. 4A, the musical tone signal applied to the musical tone signal input terminal IN is applied to one input of the differential amplifier 5, and the musical tone signal is applied to the amplitude modulation circuit 1.
It is also given to The musical tone signal given to the amplitude modulation circuit 1 is transmitted through a variable resistor VR1 and a tremolo switch S.
The amplitude is modulated by the output signal of the low frequency oscillation circuit 3 shown in FIG. , the second of this device
is applied to the second sound emitting device 7 via the output terminal CH2. On the other hand, the output of the differential amplifier 5 is a variable resistor.
VR3 is given to the first sound emitting device 6 via the first output terminal CH1 of this device. In the end, the output terminals CH1 and CH2 of this device are connected to the output terminals C and D in Figure 4, respectively.
This results in the tremolo-added musical tone signal shown in FIG. Note that the first and second sound emitting devices 6, 7
are the same in terms of performance, and the center of the instrument (or player)
However, if the first sound emitting device 6 includes a speaker for medium and high frequencies, and the second sound emitting device 7 includes a speaker for bass sounds, the tone color changes. A certain phase tremolo can be obtained, and the speaker in the first sound emitting device 6 is arranged facing forward at the front of the instrument, and the speaker in the second sound emitting device 7 is arranged facing backward at the rear surface. If you do this, you will get a phase tremolo with changes due to direct and indirect sounds.

As described above, according to this invention, phase tremolo similar to the conventional one can be obtained using one amplitude modulation circuit and one differential amplifier, and the circuit configuration has the advantage of being extremely simple and inexpensive. It is something.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of a conventional musical tone signal control device of this kind, Fig. 2 A, B, C, D, and E are signal waveform diagrams of the terminals in Fig. 1, and Fig. 3 is an embodiment of this invention. Block diagram of musical tone signal control device, No. 4
Figures A, B, C, and D are signal waveform diagrams of the terminals in Figure 3. 1... Amplitude modulation circuit, 3... Low frequency oscillation circuit,
5... Differential amplifier, 6... First sound emitting device, 7...
...Second sound emitting device.

Claims (1)

[Scope of utility model registration request] It is equipped with a low frequency oscillation circuit, an amplitude modulation circuit that performs amplitude modulation control of a musical tone signal according to an output signal of the oscillation circuit, and a differential amplifier, and guides the musical tone signal to one input of the differential amplifier and the output of the differential amplifier to the first sound emitting device; and the output of the amplitude modulating circuit to the other input of the differential amplifier and the second sound emitting device. A musical tone signal control device for an electronic electric musical instrument.