JPS623829Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a pseudo tom-tom sound generator that generates a pseudo tom-tom sound in a percussion instrument, and in particular, a pseudo tom-tom sound generator that can generate a sound that is faithful to the sound of an instrument. This is what we are trying to provide.

FIG. 1 shows a conventional pseudo tom tom sound generating device. In the figure, numeral 1 indicates a trigger signal source, from which a trigger signal having a desired rhythm is output. This trigger signal is supplied to the oscillator 2. The oscillator 2 generally uses a resonant circuit whose resonant frequency is the frequency of the tom-tom sound, and when a trigger signal is supplied, a signal at the resonant frequency corresponds to the pitch of the tom-tom according to the rhythm of the trigger signal, as shown in Figure 2. A frequency signal is intermittently outputted, and the signal is amplified by an amplifier 3 as necessary, and the sound is emitted from a speaker, thereby generating a tom-tom sound.

The tom-tom sound obtained by the conventional device can be heard as a tom-tom sound. However, when compared to the actual tom-tom sound, it was found that there was a slight difference.

The purpose of this invention is to provide a pseudo tom tom sound generating device that can produce a tom tom sound close to an actual tom tom sound.

An embodiment of this invention will be explained in detail below using FIG. 3.

In FIG. 3, parts corresponding to those in FIG. 1 are denoted by the same reference numerals and redundant explanation thereof will be omitted, but in this invention, an adder circuit 5 is provided after the oscillator 2,
This adding circuit 5 is configured to add a noise component to the tom-tom sound output from the oscillator 2.

That is, 6 indicates a white noise generator, and the white noise output from this white noise generator 6 is supplied to a low-pass wave generator 7. As shown in Fig. 4, the low-pass wave generator 7 has a characteristic of having a peak near a frequency 2c, which is twice the oscillation frequency _c of the oscillator ₂ , and emphasizes noise components near this frequency _2c . The output signal is supplied to the adder circuit 5 through the variable gain amplifier 8 . The gain of the variable gain amplifier 8 is controlled by a control signal generated by a trigger signal from the trigger signal source 1. Reference numeral 9 denotes a control signal forming circuit, which generates a gradually decreasing control voltage E _c as shown in FIG. 5B when the trigger signal S _t shown in FIG. 5A is input. This control voltage E _c controls the gain of the variable gain amplifier 8.
A white noise component _Nw having an attenuation characteristic as shown in FIG. 5C is obtained at the output of . By adding this white noise component _Nw to the tom-tom sound signal from the oscillator 2 in the adder 5, the speaker 4
For the fundamental wave of the tom-tom sound, 2 times, 3 times, 4 times
Frequency components times... are added.

In this way, by adding white noise that has a peak at a frequency component twice the fundamental frequency to the fundamental wave of the tom-tom sound, the sound emitted from the speaker 4 can become close to the actual tom-tom sound. It was confirmed.

The reason for this can be considered as follows. The sound of the tom-tam is produced by the vibration of the skin. The vibrations of the skin contain harmonics that are twice, three times, four times...more than the fundamental wave. Therefore, by adding white noise that has a peak at twice the frequency of the fundamental wave as in this invention, harmonic components are added, which is thought to bring the sound closer to the original sound.

As explained above, according to this invention, it is possible to generate a tom-tom sound close to the original sound, and it is possible to obtain, for example, a rhythm generating device with good sound.

[Brief explanation of drawings]

Fig. 1 is a system diagram for explaining a conventional tom-tom sound generating device, Fig. 2 is a waveform diagram for explaining its operation, Fig. 3 is a system diagram showing an embodiment of this invention, and Fig. 4 is a system diagram for explaining the conventional tom-tom sound generating device. A graph showing the frequency characteristics of the main parts of this invention, and FIG. 5 is a waveform diagram for explaining the operation of this invention. 1... Trigger signal source, 2... Oscillator, 4... Speaker, 5... Adding circuit, 6... White noise generator, 7... Low pass wave generator, 8... Variable gain amplifier.

Claims (1)

[Scope of Claim for Utility Model Registration] A. A trigger signal source that generates a signal at time intervals corresponding to the rhythm of the tom-tom; B. A trigger signal given from this trigger signal source that generates a signal at a frequency corresponding to the pitch of the tom-tom at the above-mentioned time. an oscillator that generates signals according to intervals; C a low-pass wave generator with a frequency characteristic that has a peak at a frequency approximately twice the oscillation frequency of this oscillator; and D a noise source that provides white noise to this low-pass wave generator. , E a variable gain amplifier that amplitude-modulates the output of the waveform generator with a characteristic of gradually attenuating in synchronization with the trigger signal and passes it through; F an adder circuit that adds the output of the variable gain amplifier and the output of the oscillator; A pseudo tom tom sound generating device comprising: