JP2537987Y2 - Tone generator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a tone generator, and more particularly, to an envelope using a corresponding order envelope function for each of a plurality of order component wave signals from component wave generating means. (E.g., a sine wave synthesis type) that synthesizes a tone signal by adding

[Background of the Invention] As a conventional musical sound generating apparatus, a user individually sets and inputs an envelope for each of a plurality of sine waves as frequency components, and when generating a musical sound, the sine wave of the order corresponding to the individual envelope is used. Is known which synthesizes a tone signal with a sine wave by controlling the envelope of the tone signal.

According to this kind of tone generator, since a plurality of sine wave signals are controlled by independent envelope functions for each frequency (for each order), a rich tone (for example, a tone with resonance exchange) is obtained. It is possible.

However, since the user has to set and input the envelope for each frequency component of the musical tone to be obtained, there is a problem that the input is very troublesome and the burden is very heavy.

[Purpose of the Invention] Accordingly, the present invention provides a tone generator which can obtain independent envelope functions for each component wave signal by a very simple input operation, and can give an action like resonance by these envelope functions. The purpose is to provide.

[Gist of the Invention] In order to achieve the above object, the present invention provides a tone signal by assigning an envelope to each of a plurality of component wave signals from the component wave generating means using an envelope function of a corresponding order. In a tone generator of the type to be synthesized, a common envelope setting means for providing a common envelope function common to all orders, and in order to obtain the above-mentioned envelope function for each order from the common envelope function provided by the common envelope setting means, Order data x whose values have been standardized according to a predetermined standard is received as a first input, and level value data w (t) obtained by standardizing the level value of the common envelope function according to a predetermined standard is received as a second input. The difference u from the level value data w (t) is calculated according to u = x−w (t), and the envelope of each order is calculated. The function F _x (t) is defined as a function G (u) of the difference u, and the function G (u) has a characteristic that varies depending on the value of u within a predetermined range of the value of the difference u. By applying the value of the difference u from the common envelope function for each order x to this function G (u), at least some of the plurality of orders of the envelope function group of the plurality of orders are used. Envelope conversion means for generating an envelope function of each order so that the envelope functions belonging to the group of envelope functions have different characteristics when a predetermined common envelope function is given. , A function f (u) <0 that satisfies f ′ (u) <0 when f ′ (u), which is a derivative of the function f (u) with respect to u, is u <0, u) using the above envelope function Is generated, so that the common envelope function has a characteristic that is amplified more as the absolute value of the difference u becomes smaller.

In one embodiment, the envelope conversion means receives, as the level value data, data representing an instantaneous level value at each time of the common envelope function, and outputs order data x of each order value and data of an instantaneous level value at each time. By calculating the difference u with respect to w (t) and calculating the value of the function f (u) with respect to this difference u at each time, it is possible to obtain the instantaneous level value at each time of the envelope function of each order. Features.

In another aspect, the envelope conversion means receives, as the level value data, target level value data representing a target level of each step when the common envelope function is expressed by a rate and a target level for each step, A difference u is obtained between the order data x of each order value and the target level value data w (t) of each step, and a value of a function f (u) with respect to the difference u is obtained for each step. It is characterized in that a target level value of each step of the envelope function of each order is obtained.

According to the present invention, it is not necessary for the user to create an envelope function for each of the orders of the component wave signals of a plurality of orders, and it is sufficient to determine only one envelope function. is there. That is, the musical sound generator uses the single envelope function as a common envelope function, and generates an envelope function unique to each order of the component wave signal from the common envelope function. Then, in this conversion, the value of the common envelope function is compared with the value of the order, and an envelope function having a value amplified by the degree of closeness is generated in a range where both values are close. As a result, a musical tone having an effect similar to resonance is obtained.

That is, according to this invention, the order data x in which the values of the respective orders are standardized according to a predetermined standard is used as the first input, and the level value of the common envelope function is standardized according to the predetermined standard. As the second input, and the difference u = x−w between the order data x and the level value data w (t)
(T) is calculated. Further, according to the invention, an envelope function of order x is defined by a function of the difference u. Therefore, an envelope function of order x is set to Fx (t), and a function of u that defines this envelope function is G
When writing (u), F _x (t) = G (u).

As described above, in the present invention, the envelope function of the order is a function of u (= x−w (t)), and changes depending on u.

Therefore, in principle, the envelope function F of order x
_x (t) depends on the magnitude of the order x (the value of the order indicated by the order data) and the common envelope function w (t) (the level value of the common envelope function indicated by the level value data). Now, considering specific level value data, the value of u will differ for each order with respect to this specific “same” level value data. Therefore, when the level value data is considered fixed, the envelope function after conversion (order envelope function) depends on the magnitude of the order x.

However, in applying the present invention, it is not necessary that the envelope functions of all orders used have already different characteristics from each other, and a predetermined common envelope function is given only to a plurality of order envelope function groups which are a part of them. If given (in relation to a given common envelope function), it is sufficient for the order envelope functions to have different properties. This means that the function G (u) of the difference u that defines the order Venvel function F _x (t) is:
This means that those having a characteristic that changes depending on the value of u can be used only in a partial range or a predetermined range, not the entire range of the value of the difference u.

This can be easily understood by assuming that the axis of the difference u is "assumed" as the frequency axis, and considering a resonance characteristic function such that the entire u has, for example, a low-pass filter characteristic. A general low-pass filter exhibits a pass characteristic with a gain of approximately 1 in a very low frequency band, and exhibits a rejection characteristic (ideally, infinite attenuation) in a sufficiently high frequency band. Considering this simulation by G (u), a certain value α
When u is smaller, G (u) = 1, and when u is larger than another certain value β (β> α), G (u) = 0. Band characteristics can be provided. When u is within the range of [α, β], a function that changes depending on the value of u is used. In the case of this invention, since resonance effect simulation is performed within the range of [α, β], α <γ <β is considered, and u increases (for example, monotonically increases) in the range of u [α, γ], and [γ , Β], a function that decreases (for example, monotonously decreases) with respect to u, that is, a function (resonance) in which u is convex upward within the range of [α, β] and peaks when u = γ Function) can be used.

In this document, such a u-value-dependent change function (resonance function) is indicated by f (u).

One example of selection of the resonance function f (u) is such that when the difference u is zero, that is, when the value of the order x is equal to the common envelope function W (t), the value decreases as the difference increases. It is to be. In another selection example, f (u) is maximized in a range where the difference u is smaller than a predetermined value, and attenuates outside the range according to the magnitude of the difference u. There are various other options.

As an example of the resonance effect, an envelope of an order near the cutoff frequency of the low-pass filter may be emphasized. For this purpose, for example, G (u) in a range (u >> 0) where the value of the order x is sufficiently higher than the value of the common envelope function W (t) is set to the minimum level (high attenuation level), and the value of the order x is set. Is the common envelope function W (t)
G (u) in a range sufficiently lower than the value of (u << 0) is set as the pass level, and the value of the order x and the common envelope function W (t)
G (u) in a range (u ≒ 0) in which the value of is close to the pass level.

Conversely, the envelope of the order near the cutoff frequency of the high-pass filter may be emphasized. This makes G (u) at u >> 0 a pass level,
G (u) at u << 0 is set to a high attenuation level, and G at u ≒ 0
It is obtained by setting (u) to a value higher than the passing level.

Also, G (u) can be set to a high attenuation level in the range of u >> 0 and u << 0, and G (u) can be set to a relatively high value in a range where the difference u is small. In this case, a resonance effect similar to a bandpass filter is obtained.

Means for converting the common envelope function into envelope functions of each order can be configured in various forms. For example, if a common envelope function is provided in the form of digital waveform data, it is directly converted to an envelope function in the form of waveform data. This can be realized, for example, by comparing each value of the waveform data of the common envelope function with the next numerical value, and calculating each value of the waveform data of the envelope function of the order according to the difference.

Instead of converting all the values of the waveform data of the common envelope function into functions and finding all the values of the waveform data of the order-specific envelope function, only a limited number of data positions (key points) of the common envelope function , A function conversion may be performed to determine a limited number of converted points, and these points may define an envelope function of a desired order. These points are stored once in a suitable memory as envelope control information, for example a set of waveform rates and levels. And
When performing envelope control on the data of the component wave signal, waveform data of the envelope of each order is generated based on the envelope control information in the memory.

In the present invention, the component wave signal is not limited to the sine wave signal. For example, a rectangular wave (for example, a rectangular wave based on a Walsh function) can be used as a component wave signal.

[Embodiment] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In this embodiment, the present invention is applied to a sine wave synthesis type tone generator.

FIG. 1 shows the overall configuration of this embodiment. The n envelope controlled sine wave generators 15-1 to 15 shown in FIG.
-N is connected to a keyboard 1 as a performance input device, a data input device 2 for inputting various data, and a global envelope memory (common envelope memory) 3. Each of the envelope control sine wave generators 15-1 to 15-n is assigned to generate a sine wave having an independent frequency based on harmonic data set by the user via the data input device 2. The global envelope memory 3 has a RAM configuration, and stores data of a global envelope function set by the data input device 2. Then, this global envelope function is converted into data of an envelope function specific to the assigned frequency (order) inside each of the envelope control sine wave generators 15-1 to 15-n, and the converted envelope data is used. , The internally generated sine wave is envelope controlled.

Therefore, in this embodiment, if only one global envelope function is set, n is set based on that function.
Since the number of independent envelope functions is obtained, the user does not need to set a total of n types of envelopes for each sine wave, and the effort of setting the envelope is greatly reduced.

Each of the above envelope controlled sine wave generators 15-1 to 15-n
Envelope controlled sine wave data from the adder 16
And the added signal (tone signal) is D /
The signal is converted to an analog signal by the A
8. Sound is emitted outside through the speaker 19.

The details of the envelope controlled sine wave generator are shown in FIG. A portion surrounded by a dotted line denoted by reference numeral 15 represents one of the envelope controlled sine wave generators 15-1 to 15-n as a representative. In this figure, the key code generator 4
Generates a key code corresponding to a key operated on the keyboard 1. The key code conversion device 5 converts the generated key code according to the value of the overtone data storage device 10. The overtone data storage device 10 can store overtone data (overtone order) from 0 to 31 which can be set by the user using the data input device 2, and the key code conversion device 5 uses the stored overtone data to generate a third harmonic data. The key code is converted in the manner shown in the figure. For example, when the overtone data is 1, it is converted into a key code corresponding to a second overtone. The phase angle generator 6 comprises a frequency data ROM and an accumulator.
Is converted to frequency data by the frequency data ROM, and this frequency data is accumulated by the accumulator to generate a phase angle corresponding to the key code, and the sine wave data in the sine wave ROM 7 is generated. Is read. Therefore, what is output from the sine wave ROM 7 is a sine wave signal having the frequency of the harmonic order set in the harmonic data storage device 10. In this example, the key code is converted in accordance with the harmonic data. However, the frequency data may be subjected to a process such as a bit shift to obtain frequency data corresponding to the harmonic, or the phase data output from the phase angle generator 6 may be used. The value of the angle itself may be converted into a value of the phase angle of the corresponding order. Thus, various circuit modifications are possible.

The fixed amplitude memory 11 is a RAM that stores data for controlling (scaling) the amplitude of the sine wave signal from the sine wave ROM 7 in a time-invariant manner, and can be set by the data input device 2 by the user. The scaling data stored in the fixed amplitude memory 11 is stored in each envelope control sine wave generator.
Independent values can be taken for each of 15-1 to 15-n. Accordingly, by multiplying the sine wave data from the sine wave ROM 7 by the data in the fixed amplitude memory 11 in each multiplier 8, the relative amplitudes of the n sine wave signals can be controlled independently.

The sine wave signal from the multiplier 8 whose amplitude is controlled in this way is multiplied by an envelope signal from an envelope converter 14 described later in detail, so that amplitude control with a further time change is performed, and the envelope sine Wave generator 15
Output.

As described above, the global envelope memory 3 stores n
This is for storing data of a global envelope function common to the envelope sine wave generators 15-1 to 15-n. Here, the global envelope function in the global envelope memory 3 is described by four-step rate data and level data as illustrated in FIG. The global envelope function in this format is converted into a waveform data format by the envelope generator 12 (see FIG. 5). That is, the envelope generator 12 comprises an accumulator and a comparator. After first receiving the rate data and the level data of step 1 from the global envelope memory 3, the rate data is repeatedly accumulated, and the result reaches the level data. At this point, the rate data and level data of the next step are received from the global envelope memory 3, and the same operation is repeated to obtain the global envelope waveform data.

Here, the envelope conversion device 14 converts the waveform data of the common global envelope generated by the envelope generation device into the waveform data of the envelope for each order by the overtone data (order) from the overtone data storage device 10. As a result of this conversion, a result similar to resonance is obtained.

In this example, each of the envelope conversion devices 14 generates an envelope for each order by performing the following conversion.

(B) When x <w (t) and f (x−W (t)) + R <1, F _x (t) = 1 (b) x ≧ W (t) or f (x−W (t) ) + R ≧ 1
F _x (t) = f (x−W (t)) + R (1) (where f (x−W (t)) + R <0, F _x (t))
= 0) where x is the order (corresponding harmonic data), W (t)
Is the global envelope function (envelope generator
12), F _x (t) are x-order envelope functions after conversion (outputs of the envelope conversion device 14), and R is a resonance value (depth). If x-W (t) is set to u again, f (u) is (c) f '(u)> 0 when u <0, (d) f (u) = 1 when u = 0 (e) When u> 0, f ′ (u) <0 is satisfied. Therefore, when u = 0, that is, when the value x of the order is equal to the value W (t) of the global envelope function, f (u) becomes the maximum value and the difference u (absolute value)
Is a function that decreases as becomes larger. Note that, more precisely, the functions f (u) to f (x−w
(T)) means “before expansion”, that is, before expansion to a function G (u) of u, which defines an envelope function F _x (t) of order x, and is as follows. f (u)
Is that when u <0, f ′ (u), which is the derivative of f (u) with respect to u, satisfies f ′ (u)> 0, and f (0) =
1, and f '(u) <0 when u> 0. Therefore, f (u) before expansion can be defined in the range [-ｕ, ∞] of u.
Here, a finite α (α <α <1 that satisfies f (α) = 0 or 1
0) and β satisfying f (β) = 0 or 1
It is assumed that (β> 0) exists. When f (u) is extended to G (u) of a low-pass filter type as a whole (assuming that f (α) = 1 and f (β) = 0), the range of u [−
（, Α], G (u) = 1, and G in the range of u [β, ∞]
(U) = 0, and G (u) = f in the u range [α, β].
(U). That is, f (u) before expansion defines a predetermined range [α, β] of u of G (u) that defines the envelope function F _x (t) of order x. Note that in this document, f (u) is basically used in the sense before expansion, but in any case, the envelope conversion device (envelope conversion means) “uses” f (u) and uses the envelope of order x. Generates a function.

FIG. 6A shows an example of the order envelope definition function G (u) including such an order-dependent change function f (u). The horizontal axis u is obtained by subtracting the value of the global envelope function W (t) from the order x. As shown in the drawing, G (u) is close to u = 0, that is, in the range of the order x close to the value of the global envelope function W (x).
Has been amplified, G (u) = 1 when u << 0,
When u >> 0, G (u) = 0. Therefore, it can be seen that the illustrated conversion characteristic G (u) provides a resonance effect that emphasizes components near the cutoff frequency of the low-pass filter.

And this resonance effect is given dynamically. That is, the global envelope function W (t)
Generally changes with time t. Therefore,
If a particular order x ₀ is given, W from the order x ₀
The value obtained by subtracting (t) also changes with time, moves right and left on the u-axis in FIG.
The value of (u), that is, the value F _x0 (t _i ) of the envelope function of order x ₀ at each time point t _i also changes. Then, according to FIG. 6 (A), the value of F _x0 (t _i ) is the order x at the time t _i
When the value is sufficiently smaller (lower) than the value W (t _i ) of the global envelope function at, the value becomes 1 and does not decay, and the order x becomes the value W of the global envelope function at the time t _i.
When it is sufficiently larger (higher) than (t _i ), it becomes 0 and is completely attenuated. When the order x is sufficiently close to the value W (t _i ) of the global envelope function at the time t _i, it becomes a value larger than 1. Amplified.

Stated another way, an order envelope function that takes on an amplified value at a certain point in time has an order whose value is close to the value of the global envelope function at that point in time. Therefore, the order of the emphasized component wave changes with time, and a temporally dynamic resonance effect is obtained.

 In other words, it is as follows.

The envelope generally changes its value over time (time variable function).

In the present invention, the frequency component or harmonic that has resonance (that is, a partial tone (harmonic) in a certain frequency component or frequency band is emphasized) has its harmonic value (order value x) determined by the global envelope function. This is when the instantaneous level value w (t) at time t (or the target level value for each step when the global envelope function is represented by the rate of each step and the target level).

As the time progresses from time t = 0 to time t on the time-varying common (global) envelope function, harmonic components close to the instantaneous level value at that time are emphasized (resonance is reduced). It turns out that it is.

This is a "dynamic resonance effect" anyway. That is, a temporally dynamic resonance effect is obtained, in which the order component wave emphasized (resonance applied) changes every moment as time elapses and as the instantaneous level value of the global envelope changes.

Now, it is assumed that an order envelope definition function G (u) as shown in FIG. 6A is used, while a global (common) envelope function w (t) as shown in FIG. 6B. X _n order and x _p order other than x _o order, x _n ×
Let x _o × x _p . Then, for the minimum level value 0 and the maximum level value (peak) w (t) of the global envelope function (FIG. 6 (B)), (minimum level value) 0 <x _n <x _o <x _p <w ( b) (maximum level value)

According to a characteristic of FIG. 6 (A), clearly x _n following the envelope function is highlighted when the level value of the global (common) envelope function is close to the size of x _n, greater than x _n
The level of the envelope function of the order x _o is emphasized when the level value of the global envelope function is close to the magnitude of x _o (x _o > x _n ), and the level of the envelope function of the order x _p higher than the order x _o is It is highlighted when the further closer to the magnitude of the level raised by the degree x _p of the global envelope function. Therefore, it necessarily will be dynamic resonance effect described above is generated through these three envelope function of order, of course, x _n next envelope function F shape of _xn (t) (characteristics), x _o Next shape or properties of the envelope function F _xo (t), the shape or characteristics of x _p next envelope function F _xp (t) becomes mutually different. Mathematically speaking, there exists t1 which is F _xn (t1) ≠ F _xo (t1), there exists t2 which is F _xo (t2) ≠ F _xp (t2), and F _xp (t
3) There is a t3 of ≠ F _xn (t3) (where F
_xj (t _i ) represents the level value of the envelope function of order x _i at time t _i ). Further, the magnitude of any of the orders x _n , x _o , and x _{p is} an intermediate value between the minimum level 0 and the maximum level w (b) of the global envelope function. When the above relationship is established, the level of the envelope function F _xn (t), F _xo (t), or F _xp (t) of any order is the maximum value (the highest resonance value) (1 + R). There will be a time equal to

By the way, all the orders (1 in FIG. 3)
It is not necessary for the envelope function of the order (32 to 32) to have a maximum value of (1 + R).

What if: That is, the magnitude of all the orders x used is the global envelope function w (t)
Is sufficiently higher than the peak w (b) of
This is the case where (u) = 0. Obviously, in this case, the envelope function F _x (t) of all orders is F
_x (t) = 0 becomes constant and the same.

Conversely, the magnitude of all the orders x used is the minimum value 0 of the global envelope function w (t) (eg, w
(A)) sufficiently lower, that is, G (u) = 1 when u << 0
What about the case? Obviously in this case,
The envelope function F _x (t) for all orders used is
F _x (t) = 1 is constant, and the same characteristics are obtained regardless of the order.

Obviously, such unintended, extreme examples will not serve the intended purpose.

That is, regarding the magnitude of the order x (order data x) and the level of the common (global) envelope function (level value data w (t)), the relationship between the order envelope definition function G (u) used Must be standardized according to a predetermined standard. The meaning is that the difference u = x between the data of the order to be used (order data x) and the data of the level value of the predetermined global (common) envelope function (level value data w (t)). Considering −w (t), the order envelope definition function G (u) to be used has
(A) has a characteristic that varies depending on the value of u within a predetermined range, and (b) generates the envelope function F _x (t) of each order by changing the value of the difference u to G ( When applied to u), at least some envelope functions of a plurality of orders are standardized to have mutually different characteristics (overall shape),
It means.

Then, as in the present invention, when the difference u (= x−w (t)) is regarded as the frequency information, the resonance filter characteristics of u (u is regarded as the cutoff frequency, when u is close to 0) In order to provide a characteristic in which the corresponding order component is emphasized) between the order envelope function groups, the derivative f ′ (u) of the function f (u) is u> 0.
When f '(u) <0, when u <0, f'(u)> 0
By using f (u) that satisfies the following equation, in the range where the level value w (t) of the global (common) envelope function is close to the order data x (that is, the range of u ≒ 0), the level value of the corresponding order envelope function Can generate an envelope function of each order having characteristics that are greatly increased as the absolute value of the difference u decreases.

Here, the conversion to the envelope function for each order will be specifically described. Now, it is assumed that a global envelope function W (t) as shown in FIG. 6 (B) is given from the global envelope memory 3 via the envelope generator 12. The specific order x _o is at the level of the dotted line. In this case, the envelope conversion device 14 of FIG.
Figure accordance with the conversion characteristic G (u) of (A), the Figure 6 x _o as shown in (C) following the envelope function F _xo (t)
Generate

As an aid in understanding this transformation, FIG. 6A shows the global envelope function W (t) shown in FIG. 6B.
X _o order envelope function F for some values of
The value of _xo (t) is entered. For example, as shown in FIG. 6 (B), the value W (t ₁₎ of the global envelope function at time t ₁ and t _2, W (t ₂₎ are both equal to the value of order x _o. Therefore, u = 0, and the value of G (u) at the position of u = 0 in FIG. 6 (A) is determined at the time points t ₁ and t ₂ .
x _o The value of the next envelope function F _xo (t ₁ ), F _xo (t ₂ ). X _o next envelope function F _{xo at} other times
The value of (t) is obtained similarly. In practice, the envelope converter 14 of FIG. 2 performs the above-described conversion on all data values of the global envelope function W (t) in the form of waveform data provided by the envelope generator 12.

The envelope conversion device 14 can be configured in various forms. For example, a subtractor that calculates the difference between the instantaneous value of the global envelope function W (t) from the envelope generator 12 and the value of the order x from the harmonic data storage device 10, and an address specified by the output data of the subtractor, And a memory for storing the waveform data value of the envelope function after the conversion. Alternatively, the above-described conversion characteristic function G
(U) or f (x−W in the above equation (1)
(T)) can be realized by executing an appropriate algorithm, such as a computable function. For example, a difference u = x−W (t) between the next numerical value x and the value of the global envelope function is calculated, and f (x−
W (t)), and the resonance value R is added thereto (f (f)).
(Calculation of (x−W (t)) + R), it is determined whether the difference u is negative, and it is determined whether f (x−W (t)) + R is smaller than 1. If it holds, (x <
W (t) and f (x−W (t)) + R <1), a constant 1 is used as the envelope function value after conversion, and if any of the determination conditions is not satisfied (x ≧ W
(T) or f (x−W (t)) + R ≧ 1), and determines whether f (x−W (t)) + R is negative. If not, f (x−W) + R The value is set as the converted envelope function value, and if negative, the constant 0 is set as the converted envelope function value.

The envelope conversion device 14 according to the above description converts a global envelope function in a waveform data format into an envelope function in a waveform data format by order data, and performs the conversion at all points of the waveform data. . That is, the difference u between all the level value data of the global (common) envelope function (the instantaneous level value data w (t) t at each time) and the order data x.
(= X−w (t)), and a function G for the difference u
(U) The instantaneous level value at each time of the envelope function of each order is obtained by obtaining the value of FIG. 6 (A) at each time.

On the other hand, the configuration shown in FIG. 7 converts a global envelope function represented by a set of a rate and a level as shown in FIG. 3 into an envelope function for each order of a similar format, instead of the waveform data format. Things. In other words, some points on the global envelope function W (t) are transformed according to the transformation characteristic G (u). As these points, here, peak points or breakpoints on the global envelope function W (t) (W (a), W (b), W (c), W (c) in FIG. 8)
(D), points corresponding to W (e)) and the function W
Points where the value of (t) matches the value of the order x (points corresponding to W (t ₁ ) and W (t ₂ ) in FIG. 8) are used. That is, when the global (common) envelope function is represented by the rate and the target level for each step, the target level value data representing the target level of each step is received, and the order data x of each order value and the target level of each step are received. The difference u between the value data and w (t) is obtained,
The order envelope definition function G (u) for this difference u
The target level value of each step of the envelope function of each order is obtained by obtaining the value of each step (for example, the characteristic shown in FIG. 6A).
Specifically, it is as follows.

The envelope conversion device 14A of FIG. 7 cooperates with the global envelope calculation device 14B to convert the global envelope function in the global envelope memory 3 into an order-specific envelope function expressed in a similar format.
The global envelope computing device 14B computes the instantaneous value of the global envelope function, and is basically composed of an accumulator. Each time a clock is supplied from the device 14B after the rate data is set by the envelope computing device 14B. , Add the rate data to the accumulated value up to that point,
The result is output to the envelope conversion device 14A. The envelope conversion device 14A includes a level match detector that detects a match between the accumulation result from the global envelope calculation device 14B and the arrival level data of the global envelope, that is, the target level value data of each step, and the accumulation result. And an order match detector for detecting a match between the conversion characteristic G and the order data.
According to (u), the data is converted to the accumulation result to obtain the level data of the envelope for each order (for the structure of this conversion itself, the envelope conversion device 14 shown in FIG. 2 described above).
May be the same as the configuration of the corresponding part). When a match is detected from the level match detector, the global envelope calculation device 14B is reset with the rate data of the next envelope step. Further, in order to obtain time information, the envelope conversion device 14A uses a counter for counting the number of operations of each envelope step in the global envelope calculation device 14B, and an order-specific envelope based on the difference between the level data and the time information that is the content of the counter. And a circuit for calculating the rate data.

Accordingly, for example, for a global envelope function W (t) as shown in FIG. 8B, the envelope conversion device 14A firstly performs step 1 (corresponding to the range from time a to time b in FIG. 8B). ) Is read from the global envelope memory 3,
The level data is set in the internal level coincidence detector, and the rate data is set in the global envelope arithmetic unit 14B. Then, a clock signal is given to cause the envelope arithmetic unit 14B to perform accumulation, and the internal counter is incremented by one. Internal orders coincidence detecting circuit at time t _1, consistent global envelope function value (output of the global envelope arithmetic unit 14B) and order value x _o is detected. Here, the envelope conversion device 14A
Is a conversion characteristic G whose function value is exemplified in FIG. 8 (A).
(U) (for convenience, FIG. 6 (are the same as A)) was converted according to the first results of x _o next envelope function
Reserved as step level data. Then, the difference between this level data and the immediately preceding step level data (here, there is no previous step, so it is set to zero) is calculated, and that value is used as the value of the counter at that time, that is, the envelope function of the order x _o divided by the value representing the time of the first step of the F _xo (t), to secure it as rate data of the first step of the x _o next envelope function. Then the counter is initialized for the second step of the envelope function of order x _o .

The operation of the global envelope arithmetic unit 14B is started again, and the counter is incremented by one each time the accumulation is performed. Time when the counter reaches a certain value (corresponding to point b in FIG. 8 (B))
Then, the level match detection circuit detects that the global envelope function value, which is the accumulation result, has reached the reached level. As above, the envelope conversion device 14A
Computes the level data and rate data of the second step of the x _o next envelope function. Thereafter, the rate and level data of the next step are read from the global envelope memory 3, and the same processing as described above is repeated.

As a result, Figure 8 envelope control information describing x _o next envelope function shown in (C) (a set of rate and level data) is obtained, the control information is temporarily stored in order by an envelope memory 14C You.

The envelope generating device 14D has the same configuration as the envelope generating device 12 in FIG. 2. In response to a key depression on the keyboard 1 (see FIG. 1), the envelope generating device 14D starts from the first step in the order-specific envelope memory 14C and sets the rate. And the level data are read out, and the envelope function for each order of the rate and the level expression is converted into a waveform data format. The amplitude of the corresponding order sine wave data from the multiplier 8 is controlled in the multiplier 9 by the waveform data sequentially generated from the envelope generator 14D.

The conversion characteristics G (u) of the global envelope function / order-specific envelope function are not limited to those shown in FIG. 6A and the conversion conditions (a) to (c) described above. The illustrated conversion characteristics are merely examples of conversion characteristics for obtaining a low-pass filter type resonance effect. For example, u
<< In the range of 0, G (u) = 1 is completely flat, but may be almost flat. U = 0, x =
Although the position of W (t) is the center position of the resonance, the present invention is not limited to this. For example, x = W (t) + K (K is a constant, for example) may be set as the center position of the resonance. Alternatively, cx = W (t) (c is, for example, a constant or cx is an increasing function of x) may be used as the center position of the resonance. In the former case, (x−K) can be evaluated as the value of the order x, and in the latter case, cx
Can be evaluated as the value of the order x.

Further, instead of the low-pass filter type resonance effect, the conversion characteristic G (u) may be selected such that a high-pass filter type resonance effect is obtained.

One example of this is shown in FIG. 9 (A). Such a conversion characteristic is obtained by, for example, changing (a) and (b) among the above-mentioned conditions (a) to (e) of the conversion characteristic, and instead of the condition (a), x> W (t) When f (x−W (t)) + R <1, F _x (t) = 1 is used, and instead of the condition (b), x ≦ W (t) or f (x−W (t)) When + R ≧ 1, F _x (t) = f (x−W (t)) + R (where f (x−W (t)) + R <0, F _x (t)
= 0).

The conversion characteristic G (u) may be selected so that a bandpass filter type resonance effect is obtained.

This example is shown in FIG. 9 (B). Such a conversion characteristic is obtained by, for example, replacing the conditions (a) and (b) with the conditions (c), (d) and (e) among the conditions (a) to (e) of the conversion characteristics described above. , F _x (t) = f (x−W (t)) + R (where f (x−W (t)) + R <0, F _x (t)
= 0).

Further, the resonance value R need not be a constant, but may be a variable that can be changed by the user. In this case, it is further preferable that the apparatus can be configured to follow the change of the resonance value in real time during the performance. This is, for example, in the case of the envelope converter 14 described in FIG. 2, from the global envelope function W (t) in the waveform data format, to the envelope function F _x (t) for each order in the waveform data format.
Can be executed by using the value R of the resonance according to the change in the process of generating. In the case of the envelope converter structure described in FIG. 7, for example the coefficient of depth R / R _o (here the resonance between the envelope generator 14D and a multiplier 9, R _o is the reference depth Has already been reflected in the data of the envelope memory 14C for each order. R is a resonance value specified by the user) and a multiplier for multiplying the output of the envelope generator 14D, and this multiplier. Output and envelope generator 14D
(The selected output is input to the multiplier 9) and a comparator for controlling the selection of the selector, that is, the envelope generator 14D.
Is output to a cutting level (for example, G in FIG. 6A).
(U) = 1), and the output is added to a comparator connected to the selection control input of the selector.

Finally, in the above embodiment, a plurality (n) of envelope controlled sine wave generators 15-1 to 15-n are used.
There may be a plurality in terms of functional meaning, and the meaning is not limited to hardware. For example, at least a part of the elements constituting the envelope control sine wave generators 15-1 to 15-n can be realized by TDM (time division multiplexing).

[Effects of the Invention] As described in detail above, the musical sound generating device of the present invention (the device according to the first aspect of the present invention) provides a plurality of component wave signals from the component wave generating means, In a tone generator that synthesizes a tone signal by adding an envelope using an envelope function, a common envelope setting means for providing a common envelope function common to all orders, and a common envelope function provided by the common envelope setting means In order to obtain the above-described envelope function for each order, the order data x in which the values of the respective orders are standardized according to a predetermined reference is used as a first input, and the level value w of the common envelope function is standardized according to a predetermined reference. (T) as the second input, and calculates the difference u between the order data x and the level value data w (t) as u = x−w
(T), the envelope function F of each order
_x (t) is defined as a function G (u) of the difference u, and this function G
As (u), one having a characteristic that varies depending on the value of u within a predetermined range of the value of difference u is used, and this function G (u) is used as a common envelope function for each order x. By applying the value of the difference u with respect to the envelope functions of the plurality of orders, the envelope functions of each order have different characteristics when at least some of the plurality of envelope functions are given. And an envelope converting means for generating f ′, which is a derivative of the function f (u) with respect to u.
When (u) is u <0, f '(u)> 0 When u> 0, f (u) <0 is satisfied, and the above envelope function is mainly used to obtain a common envelope. The function is the difference u
Is characterized in that the smaller the absolute value of is, the larger the amplified characteristic is. Therefore, the user does not need to create an envelope for each of the plurality of component waves, and the burden of creating the envelope is greatly reduced. Also,
As described above, the component wave signal of the corresponding order is envelope-controlled by the envelope for each order generated from one common envelope function, and as a result, the emphasized order component wave signal changes with the passage of time (each of the common envelope waveforms). (It changes depending on the value at the time), so that a rich musical tone can be generated.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the overall configuration of an embodiment of the present invention, FIG. 2 is a detailed block diagram of the envelope-controlled sine wave generator shown in FIG. 1, and FIG. 3 is a key based on harmonic data in a key code converter. Diagram showing code conversion logic, fourth
The figure shows the contents of the global envelope memory. FIG. 5 is a waveform diagram for explaining the operation of the envelope generator.
Figure waveform diagram showing an example of global envelope is converted to x _o next envelope by the envelope converter shown in FIG. 2, FIG. 7 is a block diagram showing a modification of the envelope converter configuration, FIG. 8 is 7 waveform diagram showing an example of global envelope is converted to x _o next envelope by an envelope converting the configuration shown in FIG., FIG. 9 is a waveform diagram showing a modification of the order by the envelope characteristics from the global envelope. 2 Data input device 3 Global envelope memory 7 Sine wave ROM 10 Overtone data storage device 12, 14D Envelope generator 14, 14A Envelope converter 14B Global envelope arithmetic unit, 14C …… Envelope memory by order.

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-60-225195 (JP, A) JP-A-60-225196 (JP, A) JP-A-58-36799 (JP, U) 16279 (JP, B2) JP-B-59-35034 (JP, B2)

Claims (3)

(57) [Scope of request for utility model registration] 1. A tone generating apparatus of the type which synthesizes a tone signal by applying an envelope to each of a plurality of component wave signals from a component wave generating means using an envelope function of a corresponding order. A common envelope setting means for providing a common envelope function common to the first and second, and to obtain the above-mentioned envelope function for each order from the common envelope function provided by the common envelope setting means,
Order data x in which the value of each order is standardized according to a predetermined standard is used as a first input, and level value data w (t) in which the level value of the common envelope function is standardized according to a predetermined standard
As a second input, and calculates a difference u between the order data x and the level value data w (t) according to u = x−w (t),
The envelope function F _x (t) of each order is calculated by the function G of the difference u.
(U), a function having a characteristic that varies depending on the value of u within a predetermined range of the value of the difference u is used as the function G (u). By applying the value of the difference u with respect to the common envelope function for each order x, the envelope functions belonging to at least some of the plurality of envelope function groups among the plurality of order envelope function groups may have a predetermined common function. Envelope conversion means for generating an envelope function of each order so that the envelope functions have different characteristics when given an envelope function, wherein the envelope conversion means comprises a derivative of the function f (u) with respect to u. When f '(u) is u <0, f'(u)> 0 When u> 0, f (u) <0 is generated by using the function f (u) that satisfies f (u) <0. By Musical tone generating apparatus which envelope function is characterized in that to have a large amplification properties as the absolute value decreases the difference u. 2. The tone generator according to claim 1, wherein said envelope conversion means receives data representing an instantaneous level value at each time of said common envelope function as said level value data. A difference u is calculated between the order data x of each order value and the data w (t) of the instantaneous level value at each time, and a function f (u) for the difference u is calculated.
Of the envelope function of each order by determining the instantaneous level value at each time of the envelope function of each order. 3. The musical tone generating apparatus according to claim 1, wherein said envelope converting means is configured to execute said common envelope function as said level value data by a rate for each step and a target level. Receiving the target level value data representing the target level of each step, the order data x of each order value and the target level value data w of each step
(T), a difference u is obtained, and a value of a function f (u) for the difference u is obtained for each step, thereby obtaining a target level value of each step of the envelope function of each order. A musical sound generator.