JPH0481799A - Electronic musical instrument - Google Patents

Abstract

PURPOSE:To generate natural fluctuations by adding input data which is delayed by a delay circuit and input data which is not delayed together and generating fluctuation information. CONSTITUTION:A noise generator 11 generates random noises in synchronism with a clock phis and supplies them to an input terminal 1 of a selector 21. The selector 21 selects and outputs alternate data supplied to the input terminals 1 and 0 at intervals of one cycle of a clock phi whose period is a half as long as that of the phis. Then noise data that the selector 21 selects are supplied to one input of an adder 22 and also inputted to delay circuits 23 and 24 and they are delayed by one cycle of the clock phi and supplied to the other input of the adder 22. Therefore, noises with a flat spectrum become a spectrum which smoothly decreases corresponding to an increase in frequency. Consequently, natural fluctuations are obtained by the simple structure.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electronic musical instrument that can add natural fluctuations to the pitch and amplitude of generated musical tones.

[Prior art] When fluctuations are added to the musical sounds generated in electronic musical instruments,
A more natural sound effect can be obtained.

This fluctuation component has a very low frequency (
For example, it is preferable to have a characteristic of having a peak at 3 Hz) and rapidly attenuating at high frequencies.

The applicant has proposed, for example, Japanese Patent Publication No. 45-15892 and Japanese Patent Application Laid-open No. 57-724 as a device for adding this fluctuation.
Publication No. 20 was proposed first.

The former filters white noise using a low-frequency hunt bus filter and adds a fluctuation (vibrato) component.

In the latter method, white noise is sampled at a plurality of frequencies, a waveform is obtained by adding and combining them, and a musical tone is modulated with this waveform to obtain a fluctuation effect.

[Problems to be Solved by the Invention] However, in the above proposal for filtering white noise, in order to obtain practical characteristics, the order of the filter must be increased to a certain extent, which not only increases the scale of the filter, but also increases the size of the filter. The problem is that it takes time to set the filter coefficients and other characteristics.

In addition, the previous proposal to sample white noise at multiple types of frequencies and add and synthesize them to obtain modulated noise is based on the characteristic that the frequency spectrum of modulated noise attenuates smoothly from low to high frequencies. There was a problem that the fluctuation was unnatural because it changed in a step-like manner instead of changing.

This invention was made in view of this situation, and is intended to provide natural fluctuations with a simple configuration.

[Means for Solving the Problems 1] The electronic musical instrument according to claim 1 includes a noise generating means for generating random noise, and a fluctuation generating means for processing the noise generated by the noise generating means and generating information corresponding to the fluctuation. an information forming means, a musical tone information generating means for generating pitch or envelope information of a musical tone, and a fluctuation for adding fluctuation to the pitch or envelope information outputted from the musical tone information generating means in response to the output of the fluctuation information forming means. In the electronic musical instrument, the fluctuation information forming means includes a filter unit comprising a delay means for delaying incoming horn data and an addition means for adding input data delayed by the delay means and input data not delayed. However, the filter unit 1 is characterized in that a plurality of filter units 1 to 1 are connected in cascade.

[Function] In the electronic musical instrument according to claim 1, the means for forming the fluctuation information includes a delay means for delaying input data, and an addition means for adding input data delayed by the delay means and input data not delayed. The filter unit is comprised of a filter unit consisting of a plurality of stages connected in cascade. Therefore, the configuration becomes simple and it becomes possible to generate natural fluctuations.

Furthermore, in the electronic musical instrument according to the second aspect, since the filter units are time-division multiplexed, the configuration is further simplified.

[Embodiment] FIG. 2 is a block diagram showing the configuration of an embodiment of the electronic musical instrument of the present invention.

A performance information generating section 1 including a plurality of keys (not shown), etc.
Performance information corresponding to key operations is generated and output to the pitch information generation section 2. The pitch information generating section 2 generates pitch information corresponding to the input performance information, and outputs it to the musical sound waveform generating section 4 via the adder 3. The musical tone waveform generating section 4 generates a musical tone waveform in response to pitch information (pitch information) inputted from the pitch information generating section 2 via the adder 3 . This musical sound waveform is outputted to a sound system (not shown) through the multiplier 5 and emitted as a sound.

On the other hand, the noise generator 11 (noise generation means)
Random noise (white noise) having a flat spectrum is generated and output to the processing section 12. The noise generator 11 can be constructed using, for example, an M-sequence method, an interval method, or the like. Furthermore, even periodic noise can be used as random noise in practice if its period is sufficiently longer than that of a musical tone.

The processing unit 12 processes the flat spectrum noise inputted from the noise generator 11 so that it becomes a spectrum that smoothly decreases as the frequency increases. The noise output from the processing section 12 is supplied to multipliers 13 and 14.

The multiplier 13 receives data PMS supplied from a circuit not shown.
is multiplied by the noise data input from the processing unit 12 and output to the adder 3. Data PMS is a coefficient indicating pitch modulation sensitivity, and by appropriately adjusting this coefficient, the amount of fluctuation to be added can be controlled.

The adder 3 adds the noise data inputted from the multiplier 13 to the pitch information that can be inputted from the pitch information generation section 2, and supplies the result to the musical sound waveform generation section 4.

As a result, the fluctuation component input from the multiplier 13 is added to the pitch of the musical tone generated by the musical waveform generating section 4.

On the other hand, the multiplier 14 multiplies the data AMS supplied from a circuit (not shown) by the noise data input from the processing section 12 and outputs the result to the adder 15.

Data AMS is a coefficient indicating amplitude modulation sensitivity, and by appropriately adjusting this coefficient, the amount of fluctuation to be added can be controlled.

The adder 15 adds a value of 1 to the noise data inputted from the multiplier 14 and outputs it to the multiplier 7. The multiplier 7 multiplies the envelope data input from the envelope generator 6 by the coefficient input from the adder 15 and outputs the result to the multiplier 5. Is multiplier 5 a multiplier? The musical sound data input from the musical sound waveform generator 4 is multiplied by the envelope data input from the musical tone waveform generator 4, and the result is output to the Saran 1 (system).

When there is no fluctuation component, the multiplier 7 includes an adder 15.
The coefficient 1 is input from the envelope generator 6, and the envelope data output from the envelope generator 6 is supplied as is to the multiplier 5. Furthermore, when there is a fluctuation component output from the processing section 12, data obtained by adding the fluctuation component to coefficient 19.1 is input to the multiplier 7, so that the musical sound output from the musical waveform generation section 4 A fluctuation component generated by the processing unit 12 is added to the envelope (amplitude) of the signal.

In the above, fluctuations may be added to both the pitch and amplitude of musical tones, or either one of them may be added.

The processing section 12 is configured as shown in FIG. 1, for example. In this embodiment, a two-stage filter unit is realized by time division multiplexing.

The noise generator 11 generates noise data W in synchronization with the clock φS (FIG. 3B). ,W,,W,, etc. (Fig. 3C
) is generated and supplied to the input terminal 1 of the selector 21. The selector 21, which operates using a clock φ having a period of 1/2 of the clock φS, alternately selects and outputs the data supplied to the input terminals 1 and 0 every cycle of the clock φS.
Figure D).

The data selected by the selector 21 is supplied to one input of an adder 22 (adding means), and is also input to two stages of delay circuits 23 and 24 (delay means). Now, if the selector 21 selects the noise data input from the noise generator 11, the delay circuit 23 delays this noise data (D in FIG. 3) by one period of the clock φ (E in FIG. 3). Further, the delay circuit 24 further delays the noise data delayed by the delay circuit 23 by one period of the clock φ, and supplies the delayed noise data to the other input of the adder 22 (see FIG. 3, 1?).

That is, the two inputs of the adder 22 include, for example, the noise data W output from the noise generator 11 before and after one cycle of the clock φS (FIG. 3B), and the noise data W (the third
Figure F) and W (Figure 3 D) are input. The adder 22 adds the power of both people and outputs the added output to the 1-bit shifter 25. The 1-bit shifter 25 shifts the input data by 1 bit to the LSB side, performs the same processing as when the data is multiplied by a coefficient 1/2, and obtains data S□ (FIG. 3G).

s 1= (W O+W □) / 2 Furthermore, data S
Considering the possibility that the calculation of □ may require some time, the output is shown in the figure as being slightly delayed. This value Sl is latched by the register 27 operated by the clock φ, and is supplied to the input terminal 0 of the selector 21.

Suppose that the selector 21 selects the data S input to the input terminal O (D in FIG. 3) and supplies it to one input of the adder-N adder 22. is data S that is one cycle of the clock φS. (Fig. 3F) is supplied. As a result, the output T, (FIG. 3G) of the adder 22 becomes T I = (s o + s +)/2 after some delay for calculation.

The output T of this adder 22 is changed to 1 by the 1 bit shifter 25.
After being divided by
．． 14 (Figure 3H).

The above time-division operation is sequentially repeated in synchronization with the clocks φ and φS. This example is an example in which the filter unit (.
By using a stage configuration and further increasing the time division operation to n stages, an arbitrary number of stages can be obtained.

The embodiment shown in FIG. 4 shows a configuration in which filter units are simply connected in cascade.

That is, in the embodiment of FIG. 4, the processing section 12 or
The data delayed by the delay circuit 317 and the data not delayed are added to the data added by the adder 32i, and the multiplication device 3
A processing circuit (filter unit) 341 that multiplies a coefficient 1/2 by :31 is configured in a plurality of stages (n stages) connected in cascade. This processing circuit 34i includes an averaging circuit (
functions as a low-pass filter).

The gain characteristic G(ω) for one stage of the processing circuit 34i is G
(ω)=I cos(ωT/2), as shown in FIG. The gain property Gn(ω) for n stages is Gn(ω) = (CO8(ωT/2))''.As the frequency increases, the gain decreases smoothly.Here, , T is the sampling period.

FIG. 6 shows the pitch and amplitude characteristics of the "A" sound of a male voice. It can be seen that large fluctuations occur three to four times per second.

7 A1 to A4 represent waveforms of fluctuations obtained when the number of stages of the processing circuit 34i is 32 and the sampling frequency fs is 192 Hz in the embodiment of FIG. 1 (FIG. 4). , B in the same figure is section B of A1 in the same figure.
This is an enlarged view of the image. It can be seen that fluctuations similar to the fluctuations appearing in FIG. 7 are obtained.

Moreover, FIG. 8 shows the spectrum in that case. As the frequency increases, the average value is
It can be seen that the amount decreases smoothly.

In the above description, the delay time in each delay circuit is one clock (one sampling period), but the delay time is not limited to this. Further, this delay time can also be made variable.

[Effects of the Invention] As described above, according to the electronic musical instrument according to claim 1, the fluctuation information generation means includes a delay means for delaying input data, input data delayed by the delay means, and input data not delayed. Since at least the delay means are connected in cascade in a plurality of stages, it is possible to generate natural fluctuations with a simple configuration.

Further, according to the electronic musical instrument according to the second aspect, since the filter unit is configured to perform time division multiplexing operation, it is possible to further simplify the configuration.

[Brief explanation of drawings]

1 is a block diagram showing the configuration of an embodiment of the processing section in the embodiment of FIG. 2; FIG. 2 is a block diagram showing the configuration of an embodiment of the electronic musical instrument of the present invention; FIGS. H is a timing chart explaining the operation of the embodiment in FIG. 1, FIG. 4 is an equivalent block diagram of the embodiment in FIG. 1, and FIG. 5 is a characteristic diagram of a one-stage processing circuit in the embodiment in FIG. 4. , Fig. 6 is a characteristic diagram of fluctuations in pitch and amplitude of a male voice, Fig. 7 is a waveform diagram of fluctuations obtained in the embodiment of Fig. 1, and Fig. 8 is a spectrum of fluctuations obtained in the embodiment of Fig. 1. It is a diagram. 1...Performance information generating section 2...Pitch information generating section (musical tone information generating means) 3...
・Adder (fluctuation adding means) 4... Musical waveform generation section 6... Envelope generator (musical tone information generating means) 7゛... Multiplier (fluctuation adding means) 11... Noise generator (noise generating means) 12
... Processing section (fluctuation information forming means) 13.14...
Multiplier (fluctuation addition means) 15... Adder (fluctuation addition means) 21... Selector 22... Adder (addition means) 23. 24, 311 to 31n... Delay circuit (delay means)

Claims (2)

[Claims] (1) A noise generating means for generating random noise; a fluctuation information forming means for processing the noise generated by the noise generating means and generating information corresponding to the fluctuation; and a musical tone for generating pitch or envelope information of a musical tone. An electronic musical instrument comprising an information generating means and a fluctuation adding means for adding fluctuation to the pitch or envelope information output from the musical tone information generating means in response to the output of the fluctuation information forming means, the fluctuation information forming means The means includes a filter unit including a delay means for delaying input data, and an addition means for adding input data delayed by the delay means and input data not delayed, and a plurality of the filter units are connected in cascade. An electronic musical instrument characterized by: (2) The electronic musical instrument according to claim 1, wherein the filter unit performs a time division multiplex operation.