JPS5850355B2 - Tatsuchi envelope circuit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a touch envelope circuit configured to include more harmonics of a musical tone and its sidetone components when a key is strongly pressed in an electronic musical instrument.

On a normal piano, the amount of harmonic components of the fundamental tone that is generated along with the fundamental tone when a key is pressed changes depending on the strength of the keystroke. Normally, when the key is pressed softly, there is less harmonic component, and as the key is hit harder, the harmonic component is smaller. Harmonic components increase.

Furthermore, sidetone components close to harmonics also tend to increase in amount as keys are hit harder.

On the other hand, in electronic musical instruments, touch response characteristics are applied to distinguish between strong and soft keys.
Since harmonic components and sidetone components of the fundamental sound are not particularly generated in the sound source, the sound obtained by an electronic musical instrument is different from the sound of a natural musical instrument.

SUMMARY OF THE INVENTION An object of the present invention is to provide a touch envelope circuit for an electronic musical instrument that changes the amount of harmonic components and their sidetone components depending on the strength of keystrokes to obtain a musical tone closer to a natural musical instrument.

Embodiments of the present invention shown in the drawings will be described below.

Figure 1 shows the configuration as a block diagram, where 1 is a normal touch response circuit, 2 is a nonlinear circuit, for example, a varistor 2.
31 and 32 are rectified wave circuits formed by diodes and capacitors to obtain an envelope waveform, 40 and 42 are gate circuits, and 50
, 52 are sound sources of musical tones, 5□ is a sound source that mainly generates fundamental sounds and has few harmonic components, and 52 is a sound source that contains a large amount of harmonic components in addition to the fundamental sounds.

Reference numerals 60 and 62 are low frequency filters, and the cutoff frequency of 61 is selected to be slightly higher than the fundamental sound, and the cutoff frequency of 6° is selected to be a high frequency that allows almost all harmonics and their sidetone components to pass through.

Reference numeral 7 denotes a modulation circuit which generates sidetone components for harmonics of the fundamental tone of a musical tone, and uses a phase modulation circuit or a tremolo modulation circuit.

8 is a mixing amplifier, and 9 is a speaker. Therefore 31
．． 41.61 line is the first signal line, 2, 3□, 4
The lines □, 6□, and 7 are the second signal lines, and the second signal lines are those with different characteristics of the nonlinear circuit 2, the sound source 5□, and the low frequency waveform generator 62, or a line in which the modulation circuit 7 is not inserted. may be provided in parallel.

The waveform drawn close to the gate circuits 40, 4□ is an envelope waveform obtained by the rectified wave circuits 31, 32, and the output of the touch response circuit is transmitted only to the rectified wave circuit 3 on the first signal line. The second signal line shows the signal that has passed through the nonlinear circuit 2 and the rectifying p-wave circuit 32. In both cases, the solid line shows the situation when the key is pressed hard, the broken line shows the situation when the key is pressed weakly, and the horizontal axis shows the time after the key is pressed. ing.

That is, on the first signal line, the envelope waveform applied to the gate circuit 41 is proportional to the output of the touch response circuit and is a slowly sustained waveform, and on the second signal line, the envelope waveform applied to the gate circuit 41 is a waveform with nonlinear characteristics relative to the output of the touch response circuit. It has a waveform that attenuates immediately.

Since the harmonic components of the output of the filter 6 are cut, the harmonic components do not reach the mixer 8 from the beginning of the envelope waveform, that is, immediately after the key is pressed.

The output of the harmonic wave generator 62 initially contains a large amount of harmonic components and reaches the modulation circuit 7, but as the envelope waveform rapidly attenuates with time, both the fundamental tone and the harmonic components quickly disappear.

If the key is pressed strongly, the envelope waveform will look like a solid line, and if the key is pressed weakly, it will look like a broken line. Therefore, when the key is pressed strongly, a harmonic with a large amplitude will be applied to the input of the modulation circuit 7. The output of the system will generate a large amount of harmonic components and their sidetones.

The mixing amplifier 8 mixes the output of the second signal line containing the sidetone and the output of the first signal line not containing the sidetone, and outputs the mixture from the speaker 9.

The output status of the modulator 7 is shown in FIG.

The horizontal axis in FIG. 2 represents the touch response output, and the vertical axis represents the frequency.

When the keystroke P2 is strong, a large amount of sidetone is generated around the fourth harmonic, and when the keystroke is weak P1, almost no sidetone is generated.

In this way, according to the present invention, it is possible to generate a musical tone with many harmonic components and sidetones relative to the fundamental tone immediately after a key is pressed even in an electronic musical instrument, and in particular, by providing a signal line including a nonlinear circuit. Accordingly, it is possible to configure the amount of harmonics and sidetone components in each case of strong and weak keystrokes to be similar to that of a natural musical instrument, so that an electronic musical instrument with good audibility can be obtained.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention, and FIG. 2 is a diagram explaining the effect of FIG. 1. 1...Touch response circuit, 2...
Nonlinear circuit, 30, 32... Rectification filter circuit, 4
8, 42... Gate circuit, 51, 52...
・・Musical sound source, 60, 6□・・・・Low-pass filter, 7
...Modulation circuit, 8...Mixing amplifier circuit,
9...Speaker.

Claims (1)

[Claims] 1. A first signal line that controls the musical sound source output by an envelope signal proportional to the output of the touch response circuit, and a nonlinear circuit whose output changes nonlinearly in response to changes in human power, and the output of the touch response circuit is connected to the output of the nonlinear circuit. At least one system of second signal lines is provided for generating a proportional envelope signal to control musical tone sound source output, and at least one system of the second signal lines generates sidetone components for harmonic components of musical tones. A touch envelope circuit characterized by inserting.