JP3007096B2 - Musical sound wave generator - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a musical tone waveform generator, and more particularly, to a musical tone waveform generator that performs modulation to generate musical tone waveforms having various overtone characteristics.

[Conventional technology]

With the advancement of digital signal processing technology, as a first conventional example of an electronic musical instrument using the digital processing, not only a musical sound waveform having a simple characteristic but also a musical sound of a natural musical instrument, a sound of a human or a natural world (hereinafter referred to as a sound). , Collectively called natural sounds)
A PCM-type electronic musical instrument that can directly sample and memorize the sound and reproduce it at an arbitrary pitch has been realized.

On the other hand, as a second conventional example of an electronic musical instrument capable of digitally generating various types of musical sound waveforms having complicated characteristics, Japanese Patent Publication No.
There is an electronic musical instrument based on the FM system described in JP-A-54-33525 or JP-A-50-126406. This method is basically is intended to be _{e = A · sin {ω c} t + I (t) sin ω m t} ··· (A) composed musical sound waveform of the waveform output e obtained by the calculation formula, the carrier The frequency ω _c and the modulation wave frequency ω _m for modulating the frequency ω _c are selected at an appropriate ratio, a modulation index I (t) that can change over time is set, and an amplitude that can also change over time is similarly set. By setting the coefficient A, it is possible to obtain a very unique synthesized sound or the like which has complicated overtone characteristics and whose temporal overtone characteristics can change over time.

As a third conventional example that improved the FM system,
There is an electronic musical instrument described in JP-A-61-12279. This method uses a triangular wave operation instead of the sine operation of the above equation (A), and obtains a waveform output e obtained by the following equation: e = A · T {α + I (t) T (θ)} (B) Is a musical sound waveform. Here, T (θ) is a triangular wave function generated by the carrier phase angle θ. Then, the carrier wave phase angle α and the modulation wave phase angle θ are advanced at an appropriate traveling speed ratio, and the modulation index I (t) and the amplitude coefficient A are set in the same manner as in the first conventional example, so that the tone waveform can be obtained. Can be synthesized.

[Problems to be solved by the invention]

With the background of the related art as described above, in recent years, there has been a demand for an electronic musical instrument to have a performance capable of dynamically generating from a very individual musical tone unique to an electronic musical instrument to a natural sound.

However, the first conventional example of a PCM electronic musical instrument is:
Although he is very good at producing natural sounds themselves, he is not good at processing when processing natural sounds to produce individualized timbres.

That is, for example, when it is desired to continuously change from the original sound to a sine wave or the like, a sine wave is obtained by removing a harmonic component of the original sound with a digital filter or an analog filter or the like. Becomes relatively large, and if it is attempted to change the characteristic by a time function such as an envelope, it is necessary to store a filter coefficient corresponding to the characteristic of the filter in addition to natural sound data. On the other hand, the analog filter has a problem that it is difficult to obtain desired characteristics and that it is not possible to perform a time-division operation for generating a plurality of musical sounds in parallel.

Further, in contrast to the above, when it is desired to continuously change from the original sound to a musical tone having a more complex overtone structure, a method of removing the overtone structure of the original sound with the above-described filter may not generate a new harmonic component. There is a problem that it is impossible.

In general, in an acoustic piano or the like, for example, when a key in a low frequency range is pressed and when a key in a high frequency range is pressed,
Also, the tone differs considerably depending on whether the key is pressed weakly or strongly. If such a difference in tone colors is to be realized by the PCM method, data for each tone color must be stored one by one, resulting in a problem that the cost becomes extremely high. Since the processing of the musical tone characteristics is difficult as described above, there is a problem that it is more difficult to generate a musical tone whose characteristics continuously change between a high frequency range and a low frequency range. .

On the other hand, for example, musical tones of an actual musical instrument such as a piano include harmonic components of a plurality of frequencies that are integral multiples thereof in addition to a fundamental component based on the pitch frequency, and there are considerably higher harmonic components. Furthermore, non-integer multiple harmonic components may be included. Also, depending on the type of the musical instrument, the proportion of each higher harmonic is different, etc., and various musical instruments have various overtone characteristics. As described above, a musical tone with rich sound quality is generated due to the presence of harmonic components unique to each musical instrument. However, the electronic musical instrument based on the FM method, which is the second or third conventional method, is very good at manipulating the overtone composition of the musical tone to be produced, but as an output, it is unique to each instrument as described above. In order to obtain a desired musical tone, it is difficult to optimally set the parameters.

That is, in the second conventional example, since the modulation based on a sine wave is the basis, the tone generated by the equation (A) concentrates its frequency components on lower-order (lower-frequency) harmonic components. Even if the modulation index I (t) is set to a large value and the modulation is deepened, a high-order (high-frequency) harmonic component does not appear well. Therefore, the second conventional example has a problem in that it is not possible to generate a musical tone having rich sound quality such as an actual musical tone, and the tone quality of the musical tone that can be generated is limited.

On the other hand, in the third conventional example based on the formula (B), since the modulation is basically based on a triangular wave including many harmonics, a musical tone that clearly exists as a frequency component up to a higher harmonic component is considered. Although it can be easily generated, if it is desired to obtain a desired musical sound as an output, the traveling speed ratio of the carrier wave phase angle α and the modulation wave phase angle θ in the equation (B) and the modulation index I ( It is difficult to determine t) and the amplitude coefficient A optimally. In addition to this, in the third conventional example, since the triangular wave is driven by a triangular wave, for example, in the process of gradually attenuating the tone after the tone starts, its amplitude decreases in order from the higher harmonic components. Eventually, there is a problem that a process in which only a single sine wave component corresponding to the pitch frequency is finally impossible cannot be realized.

Further, in the case where the musical tone waveform to be obtained has a waveform that changes with the lapse of time after the start of sound generation, in each of the second and third conventional examples, each parameter is set so as to obtain a desired waveform with the lapse of time. Is even more difficult.

An object of the present invention is to be able to faithfully produce a plurality of natural sounds whose characteristics continuously change with a small circuit scale,
Another object of the present invention is to make it possible to easily and continuously control the overtone component and easily synthesize a tone such as a single sine wave.

[Means for solving the problem]

The first embodiment of the present invention has the following configuration.

First, there is provided a carrier signal generating means for generating a carrier signal for each waveform section corresponding to each of a plurality of waveform sections in an original waveform of a tone signal generated by playing a musical instrument. The means is, for example, a means for inputting a carrier phase angle signal that repeats an operation in which the phase angle sequentially increases linearly with time during one cycle, converts the signal into a constant function, and outputs the signal as a carrier signal. , And a ROM or the like that inputs a carrier phase angle signal as an address. The characteristics of the output carrier signal will be described later.

Next, there is provided a modulation signal generating means for generating a modulation signal for each of a plurality of waveform sections. The means is, for example, a means for receiving the carrier wave phase angle signal as input, converting the carrier wave phase angle signal according to a certain function, and outputting the modulated signal as a modulation signal. By storing a plurality of the above functions and using a predetermined selection signal as an upper address input, a plurality of modulation signals are selectively output. In this case, if the present invention is applied to a keyboard instrument, for example, a modulation signal corresponding to performance information such as key range information of a depressed key or key depressing speed information is selectively generated from the plurality. The characteristics of each output modulated signal will be described later.

Further, when the carrier signal and the modulation signal are mixed, the mixing ratio of the modulation signal to the carrier signal is controlled from 0 to an arbitrary mixing ratio, and the carrier signal and each of the modulation signals are There is a mixing control means for outputting a mixed signal mixed at a mixing ratio. The means, for example, has a value of 0 for a modulation signal output from the modulation signal generation means.
A multiplier that multiplies a modulation index that can vary from to 1;
This is an adder that adds the output signal of the multiplier and the carrier signal generated by the carrier signal generating means and outputs the result as a mixed signal. The mixing ratio can change with time after the start of the tone generation. That is, for example, the modulation index multiplied by the multiplier can be controlled so as to be multiplied by the multiplier at each time that elapses after the start of the tone generation.

Next, there is provided a normalization coefficient storage means for storing a normalization coefficient for normalizing the amplitude of the waveform section when the amplitude of the original waveform corresponding to each waveform section is divided. Since the maximum value of the absolute value of the amplitude of the sine wave stored in the ROM is normalized to 1, the same means is used for the final original waveform OR for each waveform section.
It is a ROM or the like that stores a coefficient for returning to the amplitude of G (t).

Further, there is provided a waveform output means for outputting a modulated tone waveform having a normalized amplitude with a mixed signal output from the mixing control means having a predetermined functional relationship between the input and the output. The means is, for example, a decoder that converts the mixed signal according to the above-described predetermined functional relationship and outputs the converted signal as a musical tone waveform. Alternatively, it is a ROM or the like using a mixed signal as an address input.

Next, there is provided amplitude multiplying means for multiplying the amplitude of the tone signal output from the waveform output means for each waveform section by the normalization coefficient stored in the normalization coefficient storage means. The multiplier is a multiplier for multiplying the musical tone waveform having the normalized amplitude output from the waveform output unit by a normalization coefficient read from a ROM or the like.

Along with the above configuration, the predetermined functional relationship and the carrier signal are such that, when the mixing control unit controls the mixing ratio of the modulation signal to be zero, the tone waveform generated from the waveform output unit is a sine wave or cosine. It has a relationship that becomes a wave.

The carrier signal generation means and the modulation signal generation means correspond to the modulation signal from the waveform output means when the mixing ratio of the modulation signal in the mixing control means is controlled to a predetermined mixing ratio, for example, 1. A carrier signal and a modulation signal are generated so that each desired musical tone waveform is output.

Next, a second embodiment of the present invention has the following configuration.

First, a carrier signal generating means similar to that of the first embodiment is provided.

Next, there is provided a modulation signal generating means for generating a plurality of modulation signals. The means is, for example, means for generating a plurality of modulation signals in parallel.

Subsequently, there is provided a coefficient generating means for generating a cross-fade coefficient whose sum is 1 for each modulated signal generated from the modulated signal generating means. The means includes, for example, a cross-fade data ROM corresponding to a set of cross-fade coefficients corresponding to the input of address data.

Next, there is provided a combined modulated signal output means for outputting a combined modulated signal obtained by multiplying each of the corresponding modulated signals by a cross-fade coefficient and adding them. The means includes, for example, a plurality of multipliers for multiplying each corresponding modulation signal by a cross-fade coefficient, and an adder for adding each output of each multiplier. It should be noted that the crossfade coefficient that determines the ratio when the respective modulation signals are combined is controlled in accordance with, for example, performance information such as the above-described key range information or key pressing speed information.

Further, it has the same mixing control means as in the first mode for mixing the composite modulated signal with the carrier signal and outputting a mixed signal.

 The waveform output means is the same as in the first embodiment.

And the predetermined functional relationship and the carrier signal are the first
Has a relationship similar to that of the embodiment.

On the other hand, the carrier signal generation means and the modulation signal generation means output each of the modulation signals as the synthesis modulation signal as it is by the synthesis modulation signal generation means, and the mixing control means adjusts the mixing rate of the synthesis modulation signal to a predetermined mixing rate, for example, When the control is made to be 1, the carrier signal and each modulation signal are generated so that the desired tone waveform corresponding to each modulation signal is output from the waveform output means.

[Action]

 The operation of the first aspect of the present invention is as follows.

The tone waveform output from the waveform output means basically has a characteristic obtained by converting a carrier signal output from the carrier signal generation means in accordance with a predetermined functional relationship. Are mixed with each other to add a characteristic modulated by the modulation signal.

In this case, when the relationship between the predetermined functional relationship in the waveform output means and the carrier means from the carrier signal generation means is controlled by the mixing control means so that the mixing ratio of each modulated signal becomes zero, the waveform output means Are set so that the musical tone waveform generated from becomes a sine wave or a cosine wave. This allows
If the mixing ratio of the modulation signal is set to 0 in advance by the mixing control means, it is possible to generate a musical tone waveform consisting of only a sine wave or a cosine wave.

Then, the tone waveform output from the waveform output means is multiplied by the normalization coefficient stored in the normalization coefficient storage means, so that the amplitude of the tone waveform can be matched with the amplitude of the desired waveform. .

Further, the carrier signal generation means and the modulation signal generation means, when the mixing ratio of the selectively generated modulation signals in the mixing control means is controlled to, for example, 1, each of the modulation signals from the waveform output means. A carrier signal and a modulation signal are generated such that each desired musical tone waveform corresponding to the signal is obtained. Thus, if the mixing ratio of each modulation signal is previously set to, for example, 1 by the mixing control means, a desired tone such as a tone of a natural musical instrument whose characteristic continuously changes with time after the start of sound generation. It is possible to obtain a waveform. For example, control is performed so that different modulation signals are output in accordance with the performance information, and setting is made so that each musical tone waveform of the natural musical instrument for each key range or key pressing speed can be obtained corresponding to each modulation signal. For example, it is possible to output musical sounds having various characteristics according to the performance information.

Also, during the performance, immediately after the start of tone generation, for example, the mixing ratio is set to 1 and the mixing ratio approaches 0 with the lapse of time thereafter, so that a single sine wave component or a single The frequency characteristic of the musical sound waveform can be gradually controlled so that only the cosine wave component is included. Alternatively, by changing the mixing ratio continuously to, for example, 1 or more, it is possible to control so that a unique musical tone having a more complex overtone configuration is generated from a desired musical sound waveform state.

 The operation of the second aspect of the present invention is as follows.

In the second mode, the tone waveforms of the natural musical instrument are set so as to be obtained, for example, for each key range or for each key-pressing speed, corresponding to each of the plurality of modulation signals generated by the modulation signal generating means.

Then, the combined modulation signal output means outputs the combined modulation signal while controlling the mixing ratio of the modulation signal according to, for example, performance information. Then, using the composite modulated signal output in this manner, a musical tone waveform is output via the mixing control means and the waveform output means as in the case of the first embodiment.

Therefore, the modulation signal generating means outputs, for example, two modulation signals corresponding to the respective musical tone waveforms of the natural musical instrument in the high frequency range and the low frequency range, and as the performance information, for example, information indicating that the key in the high frequency range has been pressed. Is obtained, increase the proportion of the modulated signal in the high range, and if information is obtained that the key in the low range is pressed, increase the proportion of the modulated signal in the low range, and the key in the middle range is pressed. Is obtained, the modulation signals of the high frequency range and the low frequency range are each reduced by half. This allows
It is possible to obtain a musical sound waveform that is very close to the characteristics of a natural musical instrument whose characteristics change continuously depending on the key range. In addition, it can be controlled by a key pressing speed or the like.

Of course, if the mixing ratio of the combined modulation signal in the mixing control signal is changed in the same manner as in the first embodiment,
You can obtain musical sound waveforms with various characteristics.

〔Example〕

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

Description of First Principle of One Embodiment of Musical Waveform Generator FIG. 1 is a first principle configuration diagram of one embodiment of a musical soundwave generator according to the present invention.

First, from the waveform data ROM 1, the address data Add which is input to the lower address input and increases with time is added.
According to (t), the period data F (t) and the phase difference data M
(T) and a normalization coefficient K (section) having a constant value for each waveform section (described later) are read out in synchronization with each other. In this case, the waveform data ROM 1 is set in the data is plural sets stored by the waveform selecting address data W _N to be input to the upper address input, one set is selected from among a plurality of data sets. The phase difference data M (t) [rad] is
After being multiplied by the modulation index I in the multiplier 4, the periodic data F (t) [rad] is added in the adder 3, and a sine wave (sine wave) is obtained.
Angle data F (t) .I.M (t) for modulating
Is obtained. The same data is stored in R
OM memory. It is input to the sin ROM 2 as an address signal for modulating and reading the sin wave from the sin ROM 2. sin R
The modulation output D (t) read from the OM 2 is multiplied by a normalization coefficient K (section) read from the waveform data ROM 1 for each waveform section in the multiplier 5, and then the waveform output D (t) is output.
Output as OUT (t). Here, the maximum value of the absolute value of the amplitude of the sine wave stored in the sine ROM 2 is normalized to be 1.

The operation of the musical tone waveform generator shown in FIG. 1 based on the above-described principle will be described below.

First, the original waveform ORG (t) of the musical sound waveform of a natural musical instrument, etc.
As shown in FIG. 2 (a), for example, it is divided into waveform sections A to D for each cycle section (pitch cycle) of the fundamental wave.

Then, within each waveform section, 0 [rad] or more and 2π [rad]
As shown in FIG. 2 (b), the phase angle data which sequentially increases linearly with the lapse of time t as shown in FIG.
It is assumed that periodic data F (t) [rad] read from the ROM 1 is used. Now, assume that the modulation index I in FIG. 1 is 0, and the s stored in the sin ROM 2 is based on the periodic data F (t) itself.
Read out the in-wave with its phase angle specified linearly and output
When n (F (t)) is obtained, as shown in FIG. 2 (c), a sine wave of one cycle corresponding to a phase angle of 0 to 2π [rad] in each waveform section A to D is not modulated. Is read. Each of the waveform sections A to D does not need to accurately correspond to the pitch period. In particular, in the case of a musical sound having a weak periodicity such as a percussion instrument sound, for example, from an appropriate zero-cross point (when the amplitude is 0) to a zero-cross point May be defined as one waveform section.

Next, the phase difference data M (t) read from the waveform data ROM 1 in FIG. 1 is output from the adder 3 with the value of the modulation index I multiplied by the multiplier 4 being 1 as shown in FIG. )
Using the phase angle data F (t) + M (t) shown in
When a sin wave of one cycle stored in the sin ROM 2 is read after being modulated, a waveform is output as shown in FIG.
OUT (t) is the data from which the original waveform ORG (t) for one waveform section in which the maximum value of the absolute value of the amplitude is normalized to 1 is read, and is shown in FIG. 3 (c).

Further, the normalization coefficient K (section) for each waveform section read from the waveform data ROM 1 in FIG. 1 is the absolute value of the amplitude of the sine wave stored in the sin ROM 2 in FIG. Is normalized to 1 and is a coefficient for returning to the final amplitude of the original waveform ORG (t) for each waveform section.

From the following relationship, OUT (t) = K (section) · sin (F (t) + IM ·
(1) ORG (t) = K (section) sin (F (t) + M (t)) (2) As can be understood from these relationships, when it is desired to obtain a desired original waveform ORG (t) as the waveform output OUT (t) when the value of the modulation index I is set to 1 in each waveform section, , It is necessary to obtain the period data F (t), the phase difference data M (t), and the normalization coefficient K (section) corresponding to the original waveform ORG (t). The method for obtaining this will be described with reference to the waveform section A of the original waveform ORG (t) in FIG. 2 as an example.

First, the method of deriving the periodic data F (t) is described in the second section.
This has already been described with reference to FIG.

Next, in the waveform section A of FIG.
The maximum value of the absolute value of the amplitude of (t) is defined as a normalization coefficient K (section A). Then, by dividing each amplitude value of the original waveform ORG (t) in the same section by the above-mentioned normalization coefficient K (section), normalization is performed so that the amplitude is within ± 1 as shown in FIG. I do. In FIG. 3 (a), the maximum value of both the positive and negative absolute values is 1, but the maximum value of either one may be 1 and the other may be 1 or less.

Next, the normalized original waveform OR obtained in this way is
Using G (t), phase difference data M (t) is obtained by the following processes (see FIG. 4).

First, per arbitrary time t _X in the waveform section A of the normalized original waveform ORG (t), the normalized original waveform ORG (t) corresponding to the time t _X determine the amplitude A _X (the 4 (a)).

On the sine wave whose maximum value of the absolute value of the amplitude is 1, the phase angle p _X at the position equal to the amplitude A _X obtained above is obtained (FIG. 4 (b)). In this case, the original waveform ORG (t) position of the time t and the position of _X, the phase angle p _X in the sin wave of the inner is determined to be the approximately the same relationship. That is, for example time t _X is if positioned within about 1/4 from the beginning of the waveform segment A, the phase angle also possible to determine at 0~π / 2 around within about 1/4 from the top.

And phase angle p _X which is obtained in the above, by using the period data F (t) of waveform segment A that is obtained in advance, p _X -F (t _X) corresponding to the time t _X as the phase difference data M (t _X) (FIG. 4 (c)).

The time t _X is changed over the entire area within the waveform section A to
Is repeated to obtain phase difference data M (t) corresponding to each time t of the waveform section A.

The above processing is performed by the original waveform ORG (t) shown in FIG.
Is repeated for each of the waveform sections A to D, and the cycle data F (t), the phase difference data M (t), and the normalization coefficient K (section) obtained for each waveform section are stored in the waveform data ROM 1 of FIG. I do.

By setting the value of the modulation index I multiplied by the multiplier 4 in FIG. 1 together with each of the above data to 1, and performing the above-mentioned modulation operation, the waveform output OUT (t) in FIG.
Of the original waveform ORG (t) can be obtained.

Next, in FIG. 1, by varying the value of the modulation index I multiplied by the multiplier 4, variously modulated waveform outputs OUT (t) can be obtained.

First, assuming that the modulation index I = 0, an unmodulated sine wave can be obtained in each waveform section as already shown in FIG. 2 (c).

Also, by changing the value of the modulation index I to 1.0, 1.5, and 2.0, the modulation output (D) from the sin ROM 2 in FIG.
As (t), it is possible to obtain sequentially deeply modulated waveforms as shown in FIGS. 5 (a), (b) and (c).

As described above, by changing the value of the modulation index I, various modulation waveforms can be obtained from a sine wave to a deeply modulated waveform with the original waveform as the center.

Further, by continuously changing the modulation index I from the start of sound generation to the silence, a waveform output OUT (t) is obtained that changes from a state where modulation is deeply applied to a sine wave with attenuation of a musical sound. It is also possible.

Next, in the case of the principle configuration of FIG. 1, as described above, the waveform data ROM 1 stores the cycle data F (t), the phase difference data M (t), and the normalization coefficient K (section) for each waveform section. pairs are plural sets stored by the waveform selecting address data W _N to be input to the upper address input bits, you select a set from a plurality of sets. Therefore, a different type of waveform output OUT (t) can be output for each selected set.

Then, when applying the principles of the tone waveform generation apparatus of FIG. 1, for example, in the keyboard instrument, if a waveform selection address data W _N to switch at a speed of key depression touch (strength), the key pressing speed A waveform output OUT (t) corresponding to the level can be output. Or, if the waveform selection address data W _N to switch the value of the key code can output OUT (t) different waveforms output by key range of key pressing. In general, in an acoustic piano or the like, the piano sound to be emitted differs depending on the strength of the key pressed, and the piano sound is considerably different even with a low key and a high key. Accordingly, the musical tone waveform generator shown in FIG. 1 is applied to an electronic piano or the like, and the periodic data F (t) corresponding to each of the original waveforms (piano sound of an acoustic piano) sampled in advance for each key pressing speed or key range. , Phase difference data M (t) and normalization coefficient K for each waveform section
If a set of (sections) is obtained by the above-described method and a plurality of sets are stored in the waveform data ROM 1, it is possible to obtain a very realistic tone output.

At the same time, if the value of the modulation index I is changed as described above, various modulation waveforms can be obtained from a sine wave to a deeply modulated waveform centering on an original waveform for each key range. Is obtained.

Description of Second Principle of One Embodiment of Musical Waveform Generator FIG. 6 is a second principle configuration diagram of one embodiment of a musical soundwave generator according to the present invention. The components having the same reference numerals and symbols as those of the first principle configuration diagram in FIG. 1 have the same functions.

From the waveform data ROM 6, the period data F (t) and the first phase difference data M are inputted in accordance with the address data Add (t) which is input to the address input and increases with time.
₁ (t), the second phase difference data M ₂ (t), and a constant value of a normalization coefficient K (section) for each waveform section (described later) are read out in synchronization with each other.

On the other hand, a set of cross-fade coefficients DD ₁ and DD ₂ are output from the cross-fade data ROM 7 to the multipliers 8 and 9 in response to the input of the address data CF determined for each tone generation. Note that DD ₁ + DD ₂ = 1.

First phase difference data M ₁ (t) and second phase difference data
M ₂ (t) is multiplied by the cross-fade coefficients DD ₁ and DD ₁ by the multipliers 8 and 9 respectively, and then added by the adder 10.
Phase difference data M _C (t) is generated.

Hereinafter, similarly to the case of FIG. 1, the phase difference data M _C (t)
[Rad] is multiplied by the modulation index I in the multiplier 4,
The adder 3 adds the data to the periodic data F (t) [rad], and outputs
Angle data F (t) + for modulating a wave (sine wave)
I · M _C (t) is obtained. The data is input to the ROM as an address signal for modulating and reading a sine wave from a sin ROM 2 which is a ROM memory storing the sine wave data. Modulation output D (t) read from sin ROM 2
Is multiplied by a normalization coefficient K (section) read from the waveform data ROM 6 for each waveform section in the multiplier 5, and then output as a waveform output OUT (t). Where s
The maximum value of the absolute value of the amplitude of the sine wave stored in in ROM 2 is normalized to be 1.

The operation of the musical tone waveform generator of FIG. 6 based on the above-described principle configuration will be described below.

First, the period data F (t) and the first phase difference data M
₁ (t) and the normalization coefficient K (section) are set as the cross-fade coefficient DD ₂ = 0 (DD ₁ = 1) and the modulation index I = 0, and the first source is output as the waveform output OUT (t). Waveform ORG
₁ Set so that (t) is obtained. How to set this
In the above-described first principle configuration, it is completely the same as the method performed using FIGS. 2 to 4 and the like.

Next, when the second phase difference data M ₂ (t) is set as the cross-fade coefficient DD ₁ = 0 (DD ₂ = 1) and the modulation index I = 0, the second phase difference data M ₂ (t) is set as the waveform output OUT (t). Original waveform ORG
₂ Set so that (t) is obtained. Here, if the maximum value of the _second original waveform ORG ₂ (t) is previously adjusted to be equal to the maximum value of the first original waveform ORG ₁ (t), the normalization coefficient K
(Section) can be common. Further, as described above with reference to FIG. 2, since each waveform section of the cycle data F (t) does not need to accurately correspond to the pitch cycle, the second original waveform ORG ₂ (t)
Average if the pitch period is normalized by interpolating the previously time axis so that outline equal to that of the first original waveform ORG ₁ (t), to determine the first original waveform ORG ₁ (t) of Using the set period data F (t) as it is, the second phase difference data M ₂ (t) can be determined.

Now, when the cross-fade coefficient DD ₂ = 0 (DD ₁ = 1) and the modulation index I = 1 are set, the adder 3 outputs the phase angle data F (t) + M as shown in FIG.
₁ (t) is supplied to the sin ROM 2, thereby
It is assumed that a sawtooth wave as shown in FIG. 8 is obtained as the _first original waveform ORG ₁ (t) via the line 2. Note that the amplitude is within ± 1 for simplicity. On the other hand, the crossfade coefficient DD ₁ = 0 (D
D ₂ = 1) and the modulation index I = 1, the adder 3
From the phase angle data F as shown in FIG.
It is assumed that (t) + M ₂ (t) is supplied to the sin ROM 2, whereby a rectangular wave as shown in FIG. 8 is obtained as the _second original waveform ORG ₂ (t) via the sin ROM 2. Then, the value of the address data CF input to the cross-fade data ROM 7 is changed, and a set of cross-fade coefficients DD ₁ and DD ₂ satisfying the coefficient DD ₁ + DD ₂ = 1 is output from the ROM, whereby the multiplier 8 , 9 and the adder 10, the first phase difference data M ₁ (t) and the second phase difference data M ₂ (t) are mixed at an appropriate ratio, for example, as shown in FIG. 7 (b) or (c). The following phase difference data M _C (t) is obtained. As a result, a waveform ORG _C (t) having an intermediate characteristic between the rectangular wave and the sawtooth wave can be obtained as the waveform output OUT (t) as shown in FIG.

Therefore, utilizing the above fact, first, the cross-fade coefficients DD ₁ and DD ₂ having the values shown in FIG. 9 are stored in the cross-fade data ROM 7 for each value of the address data CF. Note that only three sets are shown in FIG.
It is also assumed that each set is set to satisfy DD ₁ + DD ₂ = 1. According to the relationship of FIG. 9, when the address data CF is changed, the first phase difference data M ₁ (t) and the second phase difference data M ₂ (t) are included in the phase difference data M _C (t). FIG. 10 conceptually shows the ratio of the components included. This, in response to a change in the address data CF, characteristics of the six views waveform output OUT (t), the first original waveform ORG ₁
It is expected that the characteristic of (t) can be continuously changed to the characteristic of the second original waveform ORG ₂ (t).

Therefore, when the principle of the musical tone waveform generator shown in FIG. 6 is applied to, for example, a keyboard instrument, the first phase difference corresponding to the first original waveform ORG ₁ (t) at the time of slow key depression is stored in the waveform data ROM 6. Data M ₁ (t) and second original waveform ORG ₂ (t) when key is pressed quickly
If the second phase difference data M ₂ (t) corresponding to the key-pressing speed is changed and the value of the address data CF is switched by the touching speed (strength) of the key-pressing, Thus, a waveform output OUT (t) whose characteristics continuously change can be output.
Alternatively, the first original waveform ORG _{1 in the} bass range is stored in the waveform data ROM 6.
The second phase difference data M ₂ (t) corresponding to the second original waveform ORG ₂ (t) in the high frequency range of the _first phase difference data M ₁ (t) corresponding to (t) is stored. If the value of the address data CF is switched by the value of the key code, the waveform output OUT whose characteristics continuously change according to the key range when the key is pressed
(T) can be output.

As described below, according to the second principle configuration, only the data sets corresponding to about two types of original waveforms are stored, and a variety of waveform output OUs whose characteristics continuously change between them are provided.
T (t) can be obtained. As in the case of FIG. 1 described above, if the value of the modulation index I is changed, various modulation waveforms from a sine wave to a deeply modulated waveform can be obtained around the original waveform for each key range. Various effects can be obtained.

It is naturally possible to store two or more types of data sets and generate the phase difference data M _C (t) from the plurality of data sets. That is, for example, in the case of a keyboard instrument, a set of data corresponding to each of the original waveforms in the low, middle, and high ranges is stored.

Description of Specific Configuration of One Embodiment of Musical Waveform Generator Next, FIG. 11 is a specific configuration diagram of one embodiment of a musical soundwave generator based on the second principle configuration of FIG.
In the same figure, those having the same reference numerals and symbols as those in the principle configuration of FIG. 6 have the same functions. The waveform data ROM shown in FIG.
6 is the two ROMs of FM ROM 6 ₁ and K ROM 6 ₂ in FIG.
Consists of

In Figure 11, the period data from the FM ROM6 ₁ F (t), the first phase difference data M ₁ (t) and the second phase difference data M ₂ (t)
Address data ADD # to be input to the ROM to read
1 is an accumulator that includes an adder 12, a selector 13, and a latch 14, and sets a start address a as an initial value,
At the address interval of the pitch data d latched at
The signals are sequentially accumulated in synchronization with the rising edge of the clock CLK # 1 input to the clock signal # 14. In this case, the head address a is output from a control unit (not shown), and is selected by the selector 13 while the start pulse STRT is at the high level, and is supplied to the latch 14 as an initial value of the accumulated value. If the start pulse STRT is at a low level, the output of the adder 12 is selected and the accumulation operation is performed. The pitch data d is output from a control unit (not shown), and is latched by the latch 11 in synchronization with the rise of the start pulse STRT.

The first phase difference data M ₁ output from the FM ROM 6 ₁ (t)
And the second phase difference data M ₂ (t) are supplied to the address data CF latched by the latch 26 in the multipliers 8 and 9, respectively.
The cross-fade coefficients DD ₁ and DD ₂ output from the cross-fade data ROM (CF ROM, the same applies hereinafter) 7 in accordance with
After multiplication, the respective results are added to each other by the adder 10 to generate phase difference data M _C (t). Phase difference data M _C (t) is the multiplier 4 is multiplied by the modulation index I latched in the latch 21, and is added to the FM ROM 6 output from ₁ periodic data F (t) at summer 3. The phase angle data F (t) + I · M _C (t) thus obtained is
Input to the ROM as sin ROM 2 read address.
The address data CF and the modulation index I are both output from a control unit (not shown),
It is latched by latches 26 and 21 in synchronization with the rise of RT.

As a result, the modulation output D from the sin ROM 2 to the multiplier 5 is obtained.
(T) is output.

On the other hand, the section identification data IB output from FM ROM 6 ₁ is
The clock CLK # 1 is input to a D flip-flop (F / F, the same applies hereinafter) 15 which operates in synchronization with the rise of the clock obtained by inverting the clock CLK # 1 by the inverter 16, and an exclusive OR circuit (EOR, the same applies hereinafter) 17 To the first input of. The positive logic output Q of the F / F 15 is input to a second input of the EOR 17. The above circuit configuration, when there is a change in the value of the section identification data IB sequentially output from FM ROM 6 _1, EO
The output of R17 becomes logic "1".

The address input to the K ROM6 ₂ address data ADD #
2 is an accumulator composed of an adder 18, a selector 19 and a latch 20, with the start address b as an initial value and the EOR 17
Are sequentially accumulated one address at a time whenever the output of the data becomes logic "1". The start address b is output from a control unit (not shown). The start address STRT is selected by the selector 19 while the start pulse STRT is at the high level.
Given to. If the start pulse STRT is at a low level, the output of the adder 18 is selected and the accumulation operation is performed.

Thus, K ROM 6 ₂ to given address data ADD # 2, K ROM 6 to ₂ from the multiplier 5 the normalization factor K (section)
Is output.

In the multiplier 5, the modulation output D output from the sin ROM 2
(T) is multiplied by the normalization coefficient K (section), and the multiplication result is further multiplied by an envelope value generated by the envelope generator 22 in the multiplier 23.

The result of the multiplication is latched in synchronization with the rising edge of the clock obtained by inverting the clock CLK # 1 by the inverter 25.
Latched at 24 and output as waveform output OUT (t).

In the above configuration, the clocks CLK # 1 and CLK # 2 and the start pulse STRT are output from a control unit (not shown).

Next, the configuration of data stored in FM ROM 6 ₁ of FIG. 11 in FIG. 12.

In the figure, one set of waveform data from the start of sound generation to the mute is stored in order from the head address a, and one address has periodic data F (t) and first phase difference data M _1.
(T), second phase difference data M ₂ (t), and 1-bit section identification data IB are stored as a set. In this case, as the address advances, each of the waveform sections A, B, C, D,.
The data of each sampling point (see FIG. 2) is stored. As the waveform section changes to A, B, C, D,..., The address value of the section identification data IB becomes
In the section A, "0", in the section B, "1", in the section C, "0", in the section D, "1",... The section identifying data IB is data for updating the address specified in the K ROM 6 ₂ identifies the boundaries of the sections as described later.

Next, the configuration of data stored in K ROM 6 ₂ of FIG. 6 in FIG. 13.

In the figure, normalization coefficients K (sections) are stored one by one in order from the head address b, corresponding to each waveform section A, B, C, D,...

In FIG. 12 and FIG. 13, FIG. 9 or FIG.
As described in FIG. 10 and the like, the first phase difference data M ₁ (t)
As the second phase difference data M ₂ (t) is stored as the second phase difference data M ₂ (t).

The operation of the embodiment having the above configuration will be described with reference to the operation timing chart of FIG. Hereinafter, FIG. 11 will be referred to unless otherwise specified.

At the start of sound generation, a start pulse STRT output from a control unit (not shown) (hereinafter simply referred to as a single control unit).
Rises to logic "1" (hereinafter simply referred to as "1"; the same applies to logic "0") at the timing t1 in FIG. 14, and immediately after that, the clock CLK # 1 becomes "1" at t2. The sound generation operation is started from the timing of. In this case, the cycle of the clock CLK # 1 corresponds to the sampling cycle of musical tone generation, and the clock CLK # 2 generated by the control unit has the same cycle as the clock CLK # 1, and is 1/4 cycle from the same clock. The clock is delayed by a minute. The following operation is controlled according to the two clocks CLK # 1 and CLK # 2. In addition, the start pulse STRT maintains “1” for one cycle from the time when the clock CLK # 1 falls to “0” at the start of sound generation to the next time it falls to “0”. Maintain "0" until pronunciation starts.

First, the timing t at which the start pulse STRT from the control unit rises to logic "1" as shown in FIG.
Then, the pitch data d from the control unit is latched by the latch 11 as shown in FIG.

Subsequently, the timing t1 when the start pulse STRT is "1"
During the period from t4 to t4, the selector 13 receives the start address a from the control unit.
The start address a is latched by the latch 14 at the timing t2 when the clock CLK # 1 rises to "1", and the initial value of the address data ADD # 1 is determined as shown in FIG. 14 (d).

Thus after a small delay time t2, the period data F of the start address a of FM ROM6 ₁ (t), the first phase difference data M ₁ (t), the second phase difference data M ₂ (t) and The section identification data IB (see FIG. 12) is read out as shown in FIGS. 14 (e), (k) and (l). Thereafter, the address data ADD # 1 output from the latch 14 is fed back to the adder 12, and the pitch data d set in the latch 11 is sequentially accumulated. In this case, the accumulated value is the clock CLK
Each timing of FIG. 14 (d) when # 1 rises to "1"
At t5, t8, t11, t14, t17, etc., the new address data is sequentially latched by the latch 14 via the selector 13.
Is designated as ADD # 1, cycle data F of the corresponding address on the FM ROM6 ₁ (t), the phase difference data M (t) and section identification data IB (see FIG. 12) is FIG. 14 (e), ( k)
And (1). Since the start pulse STRT falls to "0" at t4, the selector 13 selects the output of the adder 12 after t4.

In this case, the instruction to start sounding the musical tone is given by a player pressing any key of, for example, a keyboard unit (not shown), and if the key pressed at that time is a key on the high note side. The control section latches the large pitch data d into the latch 11. Thus, the address width skipped on FM ROM 6 ₁ increases, the higher the pitch period waveform output
OUT (t) is obtained. Conversely, for example, the value 1 as the tone pitch data d if lowest note key is depressed is latched, so that each data one address is read out on the FM ROM 6 _1, the minimum pitch period waveform output OUT ( t) is obtained.

Of the data read from the FM ROM 6 ₁ As described above, the first phase difference data M ₁ (t) and the second phase difference data M ₂ (t) are input respectively to the multipliers 8 and 9. now,
At t1 when the start pulse STRT rises to "1",
Address data CF is set in the latch 26 from the control unit. Thus, from the CF ROM 7, t1 after the set of cross-fade coefficients DD ₁ and DD ₂ is output from the address corresponding to the address data CF as shown in FIG. 14 (m). Therefore, the first phase difference data M ₁ (t) and the second phase difference data M ₂ (t) are multiplied by the cross-fade coefficients DD ₁ and DD ₂ by the multipliers 8 and 9, respectively, and the results are added. Container 10
, Phase difference data M _C (t) is obtained. Although the generation timing of this data is not particularly shown in FIG. 14, the first phase difference data M ₁ (t) in FIG.
This is a timing slightly delayed from the timing of the above.

In this case, the instruction to start generating a musical tone is given by, for example, a key pressing operation on the keyboard as described above.
If the pressed key is a low-temperature key, the control unit latches it.
Small address data CF is latched at 26, and conversely, if the key is on the high temperature side, small value address data CF is latched. Therefore, according to the address data CF, CF
Since the combination of the cross-fade coefficients DD ₁ and DD ₂ output from the ROM 7 changes as described above with reference to FIG. 9 or FIG. 10, the waveform output OUT (t) whose characteristics correspond finely according to the key range is obtained. Obtainable. Of course, as described above, the address data CF is determined by the touch speed (strength) when the key is pressed.
May be switched.

Subsequently, the phase difference data M _C (t) is input to the multiplier 4. At t1 when the start pulse STRT rises to "1", the modulation index I is set in the latch 21 by the control unit. Therefore, in the multiplier 4, the phase difference data M _C (t)
Is multiplied by the modulation index I. This output is inputted to the adder 3, is added to the period data F output from FM ROM6 ₁ (t), the phase angle data F (t) + I · M C (t) is obtained.

From the phase angle data F (t) + I · M _C (t), si
n ROM 2 is accessed, and the output of the period data F (t) and the phase difference data M _C (t) (the respective timings t2, t5, t8, t11, t14, t17 of FIGS. 14 (k) and (l)) After a slight delay from immediately after (e.g., immediately after), the modulation output D (t) is output from the sin ROM 2 as shown in FIG. 14 (n).

On the other hand, the timing t1 when the start pulse STRT is “1”
During t4, the selector 19 selects the head address b from the control unit, and this head address b is latched by the latch 20 at the timing t3 when the clock CLK # 2 rises to "1". Thus, the initial value of the address data ADD # 2 is determined.

This results in a small delay time from t3, K ROM6 ₂
Is read out as shown in FIG. 14 (j). Thereafter, the address data ADD # 2 output from the latch 20 is fed back to the adder 18, and the logical output value "0" or "1" of the EOR 17 is sequentially accumulated. In this case, the accumulated values are the timings t6 and t6 in FIG. 14 (i) when the clock CLK # 2 rises to "1".
At 9, t10, t12, t15, t18, etc., the data is sequentially latched by the latch 20 via the selector 19 and the new address data AD
D # is specified as 2, K ROM 6 ₂ on the corresponding normalized coefficient address K (interval) is read as in FIG. 14 (j). Note that the start pulse STRT becomes “0” at t4.
, The selector 19 selects the output of the adder 18 after t4.

In parallel with the above operation, each of the timings t2, t5, t8, and t1 in FIG. 14 (b) when the clock CLK # 1 rises to "1".
After a slight delay from 1, t14, t17, etc., FIG.
Section identification data IB from FM ROM 6 ₁ are sequentially outputted as. This data corresponds to each of the timings t4, t7, t10, t13, and t1 in FIG. 14B when the clock CLK # 1 falls to "0".
At t6, t19, etc., the F / F15 is set and its positive logic output Q is sequentially determined as shown in FIG. 14 (f). Then, the exclusive logical sum of the section identification data IB and the positive logic output Q from the FM ROM 6 ₁ is calculated by EOR17.

Here, the section identification data IB output from FM ROM 6 ₁
Since “0” or “1” is stored alternately in each waveform section unit as shown in FIG. 12, each time the waveform section changes from A to B, B to C, C to D, etc. From "0" to "1", "1" to "0", and "0" to "1". Therefore, the output of the EOR 17 becomes "1" only when the waveform section changes, and becomes "0" at other timings. In the example shown in FIG. 14, the output of the EOR 17 becomes “1” only during the period when the clock CLK # 1 at t16 is “1” immediately after t14 when the waveform section changes from A to B. As a result, only within the above timing, the adder 18 accumulates 1 in the value b of the address data ADD # 2 from the latch 20, and the accumulated value b
+1 is latched by the latch 20 as new address data ADD # 2 at the timing t15 in FIG. 14 (b) when the clock CLK # 2 rises to "1". Accordingly, the clock CLK # in 2 "1" to the rise timing t15 later, the new address data ADD # 2 of based on the value b + 1 K ROM 6 ₂ on the normalization factor K (section B) is FIG. 14 (j) Is read as follows.

On the other hand, at another timing when the output of the EOR 17 is “0”, the accumulating operation is not performed in the adder 18, so that the latch 20
, The same address data ADD # 2 as before one timing is latched. Accordingly, at timing t6 in FIG.
In t9, t12, t18, etc., 1 timing as before normalization factor K (interval) is read as the K ROM 6 ₂ in FIG. 14 (j).

Thus, the modulation output D based on period data F of the waveform section A from FM ROM6 ₁ (t) and the phase difference data M (t)
(T) When the timing being read from the sin ROM 2, the normalization factor K corresponding the K ROM 6 ₂ to waveform segment A
(Section A) is read out, and similarly in waveform section B, K ROM6
_2, the modulation output D of each waveform section is read such that the normalization coefficient K (section B) corresponding to the waveform section B is read out.
Corresponding to (t) is output, the normalization factor K of the waveform section (section) is read from the K ROM 6 _2.

As described above, the clock CLK # 1 shown in FIG.
Rises to "1" at timings t2, t5, t8, t11, t
After a slight delay from 14, t17, etc., the modulation output D (t) is output from the sin ROM 2 as shown in FIG. 14 (n), and in parallel with this, the clock CLK # 2 in FIG. 14 (h). There after a slight delay from each timing t3 which rises to "1", t6, t9, t12, t15, t18, etc., normalization factor K (interval) is output as the K ROM 6 ₂ FIG. 14 (j) You. The modulation output D (t) and the normalization coefficient K (section) at each timing are multiplied by the multiplier 5 and further multiplied by the envelope data from the envelope generator 22 by the multiplier 23. At timings t4, t7, t10, t13, t16, t19, etc., at which the clock CLK # 1 falls to "0" in (b), it is latched by the latch 24 as shown in FIG.
The waveform output OUT (t) for each timing is determined. Here, the envelope generator 22 and the multiplier 23
Although not shown in the figure, the operation may be performed when it is desired to add an envelope other than the original waveform to the waveform output OUT (t), and is not always necessary.

By the operation described above, in the embodiment of FIG.
The same operation as the second principle configuration of the musical tone waveform generator shown in FIG. 6 shown in FIGS. 7 to 10 can be realized.

In another embodiment the Figure 11 in a specific configuration of an embodiment of a tone waveform generation apparatus, those corresponding to the waveform data ROM 6 of Figure 6, was composed of two ROM of FM ROM 6 ₁ and K ROM 6 ₂ However, if the addressing can be somewhat complicated, 1
One ROM may be used. Conversely, the periodic data F (t), the first phase difference data M ₁ (t), the second phase difference data M ₂ (t), and the normalization coefficient K (section) are stored in separate ROs.
It may be stored in M and read out synchronously.

Further, in FM ROM 6 _1, period data F (t) is 12
As shown in the figure, the value for each sampling point is stored, but within one waveform section, the periodic data F (t)
Is a linear characteristic in which the phase angle changes from 0 to 2π [rad] at each waveform section width as shown in FIG. 2 (b). Therefore, if there is a margin in the calculation time, the periodic data F
If (t) is calculated and output, the storage capacity can be saved.

In FIG. 11, the waveform output OUT for one musical tone
Although (t) is realized, it is also possible to output a plurality of musical tone waveforms in parallel by performing time-division operation of each unit.

Another Embodiment of the Principle Configuration of the Embodiment of the Musical Waveform Generator According to the first principle of the embodiment of the musical soundwave generator of FIG. 1, when the modulation index I = 0, the above equation (1) is used. OUT (t) = K (section) · sin (F (t)) · (3), and the periodic data F (t) is linear within each waveform section as shown in FIG. 2 (b). Since the normalization coefficient K (section) is constant in each waveform section,
A sine wave was obtained as the waveform output OUT (t). When the modulation index I = 1, as shown in the above equation (2), ORG (t) = K (section) · sin (F (t) + M (t)) (2) )was gotten. And the modulation index I
Can be changed between 0 and 1 to continuously change the waveform from the sine wave to the original waveform. If the value of the modulation index I is set to 1 or more, the waveform can be continuously changed from the original waveform to the further modulated waveform.

As described above, at least a sine wave and an original waveform can be output by the periodic data F (t) that changes linearly in each waveform section and the phase difference data M (t) that is difference data from the data. I do. Therefore, if a sine wave can be output when I = 0 and an original waveform can be output when I = 1, there is no need to adhere to the above equations (1) and (2), and OUT (t) = K ( Section) · f (g (F (t) + IM · (t)) (4) Any embodiment may be used as long as the embodiment realizes the operation having the relationship of.

For example, in the above equation (4), when input is α, f is given by: f (α) = (2 / π) α (0 ≦ α ≦ π / 2) f (α) = − 1+ (2 / π) (3π / 2-α) ·· (π / 2 ≦ α ≦ 3π / 2) f (α) =-1+ (2 / π) (α-3π / 2) ·· (3π / 2 ≦ α ≦ 2π) .. (5) is defined as a triangular wave function that satisfies the following expression, and g is defined as g (β) = (π / 2) sin β (0 ≦ β ≦ π / 2) g (β) = Π- (π / 2) sin β ··· (π / 2 ≦ β ≦ 3π / 2) g (β) = 2π + (π / 2) sin β ··· (3π / 2 ≦ β ≦ 2π) If defined as a function that satisfies (6), by substituting the above equations (5) and (6) into the above equation (4) when the value of the modulation index I is 0, ie, no modulation, f (g ( β)) = K (section) · f ((π / 2) sin β) = K (section) · (2 / π) (π / 2) sin β = K (section) · sin β · · (0 ≦ β ≦ π / 2) f (g (β)) = (Section) · f ((π− (π / 2) · sin β)) = K (section) · (−1+ (2 / π) (3π / 2−π + (π / 2) sin β)) = K (section) · sin β ·· (π / 2 ≦ β ≦ 3π / 2) f (g (β)) = K (section) · f (2π + (π / 2) · sin β) = K (section) · (-1 + (2 / π) (2π + + (π / 2) sin β-3π / 2)) = K (section) · sin β · · (3π / 2 ≦ β ≦ 2π) (7) Becomes That is, a single sin wave is output during no modulation.

In order to obtain the original waveform ORG (t) when the modulation index I = 1 by substituting the equations (5) and (6) into the equation (4), FIG. The sine wave of (b) is replaced with a triangular wave defined by the above equation (5).
The phase difference data M (t) is determined as the difference data from the g (t) by replacing the periodic data F (t) in FIG. 9C with the function g (t) defined by the above equation (6). do it.

In this case, as means for generating a triangular wave for the sin ROM 2 in FIG. 1, it is also possible to generate a triangular wave by a decoder circuit or the like in addition to the ROM.

In addition to the above aspects, the functions f and g satisfying the expression (4)
Can define various combinations of functions.

The above application is shown in FIG. 6 in which the periodic data F (t), the first phase difference data M ₁ (t), the second phase difference data M ₂ (t), and the normalization coefficient K in the second principle configuration The same applies to the relationship of (section).

〔The invention's effect〕

According to the first aspect of the present invention, if the mixing ratio of the modulation signal is previously set to 0 by the mixing control means, a musical tone waveform consisting of only a sine wave or a cosine wave can be generated and selectively generated. If the mixing ratio of each modulation signal in the mixing control means is set to a predetermined mixing ratio (for example, 1) in advance, it is possible to obtain a desired musical sound waveform such as a musical tone of a natural musical instrument corresponding to each mixing ratio.

Therefore, during the performance, for example, the mixing ratio is set to 1 immediately after the start of the tone generation, and the mixing ratio approaches 0 with the lapse of time thereafter, so that a single sine wave component or a single The frequency characteristic of the musical sound waveform can be gradually controlled so that only the cosine wave component is included. Alternatively, by changing the mixing ratio continuously to, for example, 1 or more, it is possible to control so that a unique musical tone having a more complex overtone configuration is generated from a desired musical sound waveform state. Further, for example, control is performed so that different modulation signals are output in accordance with the performance information, and setting is made so that each musical tone waveform of a natural musical instrument for each key range or key pressing speed can be obtained corresponding to each modulation signal. For example, it is possible to output musical sounds having various characteristics according to the performance information.

Further, the normalized amplitude of the musical tone waveform output from the waveform output means is multiplied by a normalization coefficient for each waveform section by the amplitude multiplying means, so that the output musical tone waveform has an amplitude matching the desired amplitude. It becomes possible to output. In addition, since the normalization coefficient to be multiplied for each waveform section can be changed, the amplitude of the output tone signal can be freely changed.

Next, according to the second aspect of the present invention, as each of the plurality of modulation signals generated by the modulation signal generating means, for example, each musical tone waveform of a natural musical instrument for each key range or each key pressing speed can be obtained. Can be set. Then, the combined modulation signal output means outputs the combined modulation signal while controlling the mixing ratio of the modulation signal according to the performance information, for example, and uses this combined modulation signal in the same manner as in the first embodiment. And output the musical sound waveform through the mixing control means and the waveform output means, so that the characteristics are very close to those of a natural musical instrument whose characteristics continuously change according to performance information such as key range information or key pressing speed information. A musical sound waveform can be obtained.

As described above, the present invention can easily generate both a state in which a musical tone of a natural sound is produced and a state in which only a single sine wave component or a single cosine wave component is obtained, and Various overtone characteristics close to a plurality of characteristics can be generated. Moreover, as a configuration for realizing it,
Since it can be realized only by a combination of a ROM, a decoder, an adder, a multiplier, and the like, a complicated musical sound waveform can be realized with a simple circuit configuration, and as a result, a high-quality electronic musical instrument and the like can be provided at low cost. It becomes possible.

[Brief description of the drawings]

FIG. 1 is a diagram showing a first principle configuration of an embodiment of a musical tone waveform generator according to the present invention, FIG. 2 is a diagram showing a relationship between ORG (t) and F (t), and FIG. FIG. 4 shows a relationship between ORG (t), F (t) and M (t), FIG. 4 shows a method of obtaining M (t), and FIG. FIG. 6 is a diagram showing the relationship between D (t), F (t) and M (t). FIG. 6 is a second principle configuration diagram of one embodiment of a musical tone waveform generator according to the present invention. FIG. 8 shows the relationship between M ₁ (t), M ₂ (t) and M _C (t). FIG. 8 shows the relationship between ORG ₁ (t), ORG ₂ (t) and ORG _C (t). FIG. 9, FIG. 9 is a diagram showing the relationship between CF and DD ₁ and DD ₂ , FIG. 10 is a diagram showing the relationship between CF and M ₁ (t) and M ₂ (t), FIG. FIG. 12 is a diagram showing a specific configuration of an embodiment of a musical tone waveform generator, FIG. 12 is a diagram showing a data configuration of FM ROM, and FIG. Data configuration diagram, FIG. 14 is an operation timing chart of a specific structure of one embodiment of a tone waveform generation apparatus. 1, 6 ... waveform data ROM, 2 ... sin ROM, 3, 10 ... adder, 4, 5, 8, 9 ... multiplier, 7 ... cross-fade data ROM, Add (t), CF ... ... Address data, W _N ... Waveform selection address data, F (t)... Period data, M (t), M _C (t)... Phase difference data, M ₁ (t). Phase difference data, M ₂ (t)... Second phase difference data, CF... Address data, DD ₁ , DD ₂ ... Cross-fade coefficient, I. , F (t) + I · M _C (t)
Phase angle data, K (section) ... normalization coefficient, D (t) ... modulation output, OUT (t) ... waveform output.

Claims (4)

(57) [Claims] 1. A carrier signal generating means for generating a carrier signal for each of a plurality of waveform sections corresponding to a plurality of waveform sections in an original waveform of a tone signal generated by playing a musical instrument; and a modulation signal for each of the waveform sections. A modulation signal generating means for generating, and when mixing the carrier signal and the modulation signal, the mixing ratio of the modulation signal to the carrier signal is controlled from 0 to any mixing ratio, the carrier signal and Mixing control means for outputting a mixed signal obtained by mixing the modulated signal at the mixing ratio; and normalization for normalizing the amplitude of the waveform section when the amplitude of the original waveform corresponding to each waveform section is divided. Normalization coefficient storage means for storing coefficients, an input and an output having a predetermined functional relationship, and a musical tone waveform modulated with the mixed signal output from the mixing control means as an input, Waveform output means for outputting at a given amplitude; amplitude multiplication means for multiplying the amplitude of the musical tone waveform output from the waveform output means for each waveform section by a normalization coefficient stored in the normalization coefficient storage means; Having the predetermined functional relationship and the carrier signal, wherein when the mixing control unit controls the mixing ratio of the modulation signal to be 0, the musical tone waveform generated from the waveform output unit is The carrier signal generation unit and the modulation signal generation unit are controlled such that the mixing ratio of the modulation signal by the mixing control unit becomes a predetermined mixing ratio. And generating a carrier signal and a modulation signal such that the waveform output means outputs a desired tone waveform for the modulation signal. 2. The musical tone waveform generator generates a corresponding musical tone waveform based on performance information generated in response to a performance operation. The modulation signal generating means converts the performance information from a plurality of modulation signals to the performance information. The musical tone waveform generator according to claim 1, wherein a corresponding modulated signal is selectively generated. 3. A carrier signal generating means for generating a carrier signal for each waveform section corresponding to each of a plurality of waveform sections in an original waveform of a musical tone signal generated by playing of a musical instrument; Modulation signal generation means for generating a modulation signal; coefficient generation means for generating a crossfade coefficient having a total sum of 1 corresponding to each modulation signal generated by the modulation signal generation means; A composite modulation signal output unit that outputs a composite modulation signal obtained by multiplying and adding the modulation signal, and a mixing ratio of the composite modulation signal to the carrier signal in a case where the composite modulation signal is mixed with the carrier signal from 0 to an arbitrary value. Mixing control means for controlling the mixture signal up to the mixing ratio and outputting a mixed signal obtained by mixing the carrier signal and the composite modulation signal at the mixing ratio; A normalization coefficient storage means for storing a normalization coefficient for normalizing the amplitude of the waveform section when the amplitude of the corresponding original waveform is divided; and an input and an output having a predetermined functional relationship; Waveform output means for outputting a modulated tone waveform having a normalized amplitude with the mixed signal output from the means as an input; and outputting the tone waveform amplitude output from the waveform output means for each waveform section to the amplitude. Amplitude multiplying means for multiplying the normalization coefficient stored in the normalization coefficient storage means, wherein the predetermined functional relationship and the carrier signal have a mixing ratio of the combined modulation signal of 0 by the mixing control means. When controlled so that the tone waveform generated from the waveform output means becomes a sine wave or cosine wave, the carrier signal generation means and the modulation signal generation means, Strange Each of the modulation signals is output as a composite modulation signal corresponding to the cross-fade coefficient output from the coefficient generation means by the signal output means, and the mixing rate of the mixed modulation signal becomes a predetermined mixing rate by the mixing control means When controlled as above, a carrier signal and each modulation signal are generated such that a desired tone waveform for each modulation signal is output from the waveform output means. 4. A musical tone waveform generating apparatus according to claim 1, wherein said musical tone waveform generator generates a corresponding musical tone waveform based on performance information generated in response to a performance operation. The tone waveform generator according to claim 3, wherein a ratio of each modulation signal is controlled based on the performance information.