JP2580795B2 - Electronic musical instrument - Google Patents

Description

The present invention relates to an electronic musical instrument suitable for generating various musical tones.

2. Description of the Related Art Conventionally, in an electronic musical instrument, a musical tone signal output from a sound source is passed through a filter having a variable frequency characteristic in order to give a musical tone a tone unique to the musical instrument. Hereinafter, typical electronic musical instruments will be described.

First, the first conventional electronic musical instrument (No. 50-114319)
Will be described with reference to the block diagram shown in FIG. In this figure, an envelope circuit 2 includes a keyboard 1
Generates a control waveform signal in response to the key operation. Next, the opening / closing circuit 3 is controlled to open / close according to the control waveform signal, and a tone signal corresponding to the pitch of the operation key is derived from the sound source 4.
Then, the frequency characteristic of a VCF (Variable Voltage Control Variable Filter) 5 is varied by the control waveform signal, a specific tone is given to the tone signal from the switching circuit 3, and the tone signal is emitted from the speaker SP through the amplifier AMP.

Next, a second conventional electronic musical instrument (Japanese Patent Publication No. 64-7400) will be described with reference to a block diagram shown in FIG.
In this figure, a digital filter 7 is used for controlling the timbre of a musical tone. The digital filter 7 has a filter in advance at predetermined time intervals (frames) and in accordance with touch information from the keyboard 1. Characteristic parameter memory 8
Are supplied to the filter characteristic parameters.
As a result, the characteristics of the digital filter 7 change, giving time variability to the tone signal output from the waveform memory 9. And a D / A (digital / analog) converter 10
Is converted into an analog signal by the sound system SD.

[Problem to be Solved by the Invention] By the way, in the conventional electronic musical instrument shown in FIG. 13, the frequency characteristic of the VCF is changed by an envelope circuit according to the key pressed, but the envelope waveform is changed according to the touch information. Variable speed (rate) cannot be variably controlled.
Therefore, the electronic musical instrument has a disadvantage that only a simple tone can be obtained.

Next, the electronic musical instrument shown in FIG. 14 has a configuration in which the supply speed of the filter characteristic parameter to the digital filter can be changed in order to change the change speed of the digital filter according to some performance information. Or
Alternatively, a large number of filter characteristic parameter groups must be stored so as to indicate a change for each piece of performance information. Therefore, such a conventional electronic musical instrument has a problem that the scale of the device is increased.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and is an electronic musical instrument capable of expanding the possibilities of musical expression and providing various tone changes to musical sounds without increasing the scale of the device. It is intended to provide.

[Means for Solving the Problems] In order to solve such a problem, according to the invention described in claim 1, key information generating means for outputting tone information including touch information at the time of key release, and the tone information Filter means for filtering a tone signal generated in accordance with the condition, filter envelope generating means for generating a filter envelope for temporally changing the characteristics of the filter means, and the filter in accordance with the touch information at the time of key release. Envelope control means for controlling a filter envelope generated by the envelope generating means, wherein the larger the touch information at the time of key release, the faster the changing speed of the filter envelope generated by the filter envelope generating means; Based on the filter envelope generated by the filter envelope generating means, Filter control means for controlling characteristics of the filter means.

According to a second aspect of the present invention, in the electronic musical instrument according to the first aspect, the filter unit includes a plurality of filters, and the filter control unit includes a filter for at least one of the plurality of filters of the filter unit. The characteristic is controlled based on the filter envelope generated by the filter envelope generating means.

[Operation] When the key information generating means outputs tone information including touch information at the time of key release, the tone signal generated according to the tone information is filtered by the filter means whose characteristics are controlled based on the filter envelope. At that time,
The envelope control means controls the temporal change rate of the filter envelope faster as the touch information at the time of key release is larger.

"Example" Next, an example of the present invention will be described with reference to the drawings.

A. Configuration of the embodiment. FIG. 1 is a block diagram showing the configuration of one embodiment of the present invention. In this figure, reference numeral 11 denotes a keyboard, and a key code
It outputs KC, key-on signal KON, key-off signal KOFF, key-on speed KV, and key-off speed KOFFV (touch information) to the system controller 3. Reference numeral 12 denotes an operator, which includes various operators such as a volume and a pitch vent. In addition, the operation unit 12 outputs musical sound information according to the state of each operation unit to the system controller 13. Next, the system controller 13 includes, for example, a CPU (Central Processing Unit), a storage device, and the like, and controls the entire electronic musical instrument according to a predetermined program. The system controller 13 executes the key code
KC, key-on speed KV, key-off speed KOFFV, key-on signal KON, key-off signal KOFF and tone color parameters based on the tone information are output to tone waveform generator 14. Also, to the filter system 15, various tone designation information (a target value fn, a current value fd, an interpolation speed Si, a filter designation number n of the cutoff frequency f) for changing the cutoff frequency f (filter characteristics) by time division. And reset signal IR)
Is output. Further, it outputs a volume signal VOL and the like to the level control unit 6. Next, the musical tone waveform generator 14 performs the key code KC, the key-on speed KV, and the key-off speed KOFF.
The tone waveform data is generated in accordance with V, the key-on signal KON, the key-off signal KOFF, and the tone color parameters, and the tone waveform data is output to the filter system 15. This filter system 15 forms a multi-stage filter by time division, and when the target value fd and the current value fn of the various musical tone designation information are set (fd ≠ fn), the cutoff frequency of the filter system 15 f changes from the current value fn toward the target value fd at a change speed corresponding to the value of the interpolation speed Si. As a result, the tone waveform data passing through the filter system 15 is filtered in a complicated manner. The musical sound waveform data is supplied to the level control unit 6. Further, the filter system 15 determines that the cutoff frequency f is equal to the target value.
When fd is reached, an interrupt signal Int corresponding to each stage filter is output to the system controller 13. Level control unit 6
Generates and outputs a tone signal from tone waveform data according to a volume signal VOL or the like.

Next, the configuration of the filter system 15 of this embodiment will be described with reference to the block diagram shown in FIG.

. Configuration of filter system 15. In this figure, a filter system 15 includes a controller unit 16, selectors 17, 18a, 18b, REGs (registers) 19a, 19
b, 19c, 19d, 19e, 19f, a DCF (digital filter) 20, a multiplication coefficient generator 21, and the like.

The control unit 16 controls the operation timing of each unit, supplies necessary data to each unit, and controls the whole. The control unit 16 is supplied with a system clock φ, the above-mentioned various musical sound designation information, and the like. Further, the control unit 16 controls the selector signals S0, S1 and S3.
To the selector 17, the control signals RC1 to RC6 to the registers 19a to 19f, the H / L signal to the selector 18a, and the cutoff frequency data f to the DCF 20.

Then, REG19a is an input register for latching the tone waveform data, the input terminal of the selector 17 the musical tone waveform data on the basis of a control signal RC1 Q ₀ and the adder 22
Supply to

The selector 17, in response to the selector signal S0, S1, S2 as described above, outputs one of data supplied to a plurality of input terminals Q ₀ to Q ₄ selectively to DCF20.

The DCF 20 includes adders 20a and 20a, multipliers 20b and 20b, a delay unit 20c, and a log-lin conversion table 20 as shown in FIG.
It is composed of The cutoff frequency f of this DCF20
Is controlled by directly giving a parameter logα corresponding to the logarithmic value of the cutoff frequency f. The DCF 20 has outputs as an HPF (high-pass filter) and an LPF (low-pass filter). DCF20 H
Each output of the PF and the LPF is supplied to the selector 18a. Here, the subscript n of Dn in the delay unit 20c corresponds to the number of time division filters and the number of simultaneous sounding channels. For example, in a system in which one sound is formed by four filter units and 16 sounds can be generated simultaneously, the delay unit 20c is configured by a 16 × 4 stage shift register.

The selector 18a selects one of the musical tone waveform data supplied through the HPF or the LPF in accordance with the above-described H / L signal, and outputs it to the multiplier 23 and the REG 19b.

Next, REG19b responds to the control signal RC2 by DCF
Reference numeral 20 denotes a register for latching the output tone waveform data. The tone waveform data output by this REG19b is
The input terminal Q _{1 of} 17 is supplied to a secretor 18b.

Further, the multiplication coefficient generator 21 generates a multiplication coefficient a based on various musical tone designation information, and outputs the multiplication coefficient a to the multiplier 23.

The multiplier 23 controls the level of the tone waveform data by multiplying the tone waveform data output from the secretor 18a by the multiplication coefficient a. The tone waveform data of which the level is controlled is supplied to REG19c and REG19d.

REG19c is a register that latches the tone waveform data whose level has been controlled in accordance with the control signal RC3. The tone waveform data from the REG 19c is stored in the selector 17 described above.
, The input terminal Q ₂ , the secretor 18 b and the adder 22.

The adder 22 receives the tone waveform data output from the REG 19a and the REG1
9c is the sum of the tone waveform data to be output, and supplies to the input terminal Q ₃ of secretase 17. REG19d is a register for temporarily storing the tone waveform data from the multiplier 23 according to the control signal RC4. The output data of this REG19d is
It is supplied to the input terminal Q ₄ of the selector 17.

Next, in response to the select signal S3, the secretor 18b
The output data of 19b or REG19c is selectively output to the adder 24. The output data of the adder 24 is output to the REG 19e.

REG19e is an accumulator register, and temporarily holds output data of the adder 24 according to the control signal RC5. The output data of the REG 19e is supplied to the REG 19f and the adder 24. That is, the adder 24 adds the output data of the secretor 18b and the output of the REG 19e. Therefore, the output data of the selector 18b and the R
The result of adding the content of EG19e itself is retained.

REG19f is a filter flow output register which holds and outputs final musical tone waveform data by the filter system 15.

Next, a multi-stage filter flow configured by the above-described filter system 15 will be described.

i. Configuration of filter flow. In the filter system 15, the selectors 17, 18a, 18b and the registers 19a to 19f are controlled by the select signals S0 to S3 and the control signals RC1 to RC6 output from the control unit 16 at a predetermined timing. (A)
(G) constitute a multi-stage filter flow.

Hereinafter, the details of the multi-stage filter flow will be described with reference to FIGS. 4 (a) to 4 (g).

In this figure, FU1, FU2, FU3, and FU4 are filter units, each of which is obtained by using the DCF 20 a plurality of times by time division. Each filter unit
FU1 to FU4 are numbered in the order of time series used. A1 to A4 are multipliers for controlling the level of musical tone waveform data passing through respective signal paths. These multipliers A1 to A4 correspond to the multiplier 23 shown in FIG. 2, and are denoted by reference numerals in the time series used. In addition, each multiplier A1 ~
The level control values a _{1 to} a ₄ in A4 are calculated by the multiplication coefficient generator 21.
Are the multiplication coefficients output, and are controlled independently of each other. An example of this level control multiplier A1~A4 value a ₁ ~a ₄ shown in FIG. 5. Although FIG. 2 shows an example in which a predetermined change is made with respect to the passage of time, the change gradient and the level value may be variable according to the musical tone designation information (such as touch).
The multiplier A2 shown in FIG. 4 (a) is for controlling the amount of feedback in the feedback path. This multiplier A2
Has a function of giving resonance characteristics to the frequency characteristics of the entire filter flow shown in the figure.

Next, the operation of the filter system 15 for constructing the above-described multi-stage filter flow will be described with reference to FIG.
This will be described with reference to FIGS. 4 and 6 (a) and 6 (b).

ii. Operation of the filter system. For example, as shown in FIG.
When U4 is connected in series and a filter flow in which feedback is applied to the whole by the multiplier A2 is configured, each unit operates and proceeds in the procedure shown in FIG. 6 (a). First, tone waveform data W ₀ is supplied to REG19a, it is latched. In this case, the selector 17 uses the select signals S0 to S2 output from the control unit 16 to
Is selected to output the data supplied to the input terminal Q _3. Accordingly, the output data of the selector 17 becomes the result of the addition of the output data of the musical tone waveform data W ₀ and REG19c. The previous tone waveform data W- ₁₄ 'is latched in REG19c. Accordingly, the output data of the selector 17, becomes the musical tone waveform data W ₀ and tone waveform data W _-14 'and are added. Here, the output data of secretase 17 and tone waveform data W _01. This sound waveform data W ₀₁
Is supplied to the DCF 20. Then, ( 'see, tone waveform data W ₀₁ Fig. 4 (a) W _01)' is filtered by DCF20 as supplied to the multiplier 23 and REG19b. The REG 19b latches the tone waveform data W ₀₁ ′.

Then, the selector 17, the select signal S0~S2 the control unit 16 outputs, selectively switched to output the data supplied to the input terminal Q _1. Therefore, the selector 17 outputs the output data of the REG 19b to the DCF 20. The REG19b, because tone waveform data W ₀₁ 'is latched, is the same waveform data filtering again. The above-described filtering is repeated twice more, and the DCF 20 sequentially outputs the tone waveform data W ₀₂ ′, W ₀₃ ′ and finally the tone waveform data W ₀₄ ′ (FIG. 4A)
W ₀₂ ′, W ₀₃ ′ and W ₀₄ ′). Then, the last tone waveform data W ₀₄ ′ is latched by the REG 19 b. Then, the selector 18b supplies the adder 24 with the output data of the REG 19b, in this case, the musical sound waveform data W ₀₄ ′, according to the select signal S3. In the adder 24, the output data of the REG 19e and the musical tone waveform data W ₀₄ ′ are added. The contents of REG19e are
Since it is cleared by "0" by the initial setting, the output data of the adder 24 becomes the musical sound waveform data W ₀₄ ′. The tone waveform data W ₀₄ ′ is latched by the REG 19 e. The tone waveform data W ₀₄ ′ latched by the REG 19 e is latched by the REG 19 f and output as it is.

In this way, the filter processing shown in FIG. 4A is configured by time-sharing the required number of times of signal processing.

Next, as another example, the filter shown in FIG.
The case where the flow is configured will be described.
The operation and calculation proceed according to the procedure shown in FIG. First,
Musical tone waveform data W ₀ is supplied to the REG19a. The musical sound waveform data W ₀ is latched in REG19a, is output. In this case, the selector 17 is the select to output the input Q _0. Thus, output data of the selector 17, the musical tone waveform data W _0. The musical sound waveform data W ₀ is filtered by DCF20, '(see FIG. 4 (c) W ₀₁ which as is supplied to the multiplier 23 and REG19b') musical sound waveform data W _01. The REG 19b latches the tone waveform data W ₀₁ ′. The multiplier 23 is supplied with the multiplication coefficient a ₁ shown in FIG. 5 output from the multiplication coefficient generator 21. The multiplier 23 in this case corresponds to the multiplier A1 shown in FIG. The level of the tone waveform data W ₀₁ ′ supplied to the multiplier 23 is controlled in accordance with the multiplication coefficient a ₁ . Here, the musical sound waveform data level control "and (FIG. 4 (c) W _01" W ₀₁ see). The level-controlled tone waveform data W ₀₁ ″ is latched by the REG 19c and supplied to the adder 24 via the selector 18b. The adder 24 generates the tone waveform data W ₀₁ ″ and REG 19e.
Is added to the output data. In this case, the sixth
Similar to FIG. (A), because the content of REG19e is initially set to "0", the output data of the adder 24 is tone waveform data W ₀₁ "becomes. Accordingly, the musical tone waveform data W _01"
Is latched by REG19e as it is.

Then, the selector 17, the selector signal S0~S2 the control unit 16 outputs, selectively switched to output the data supplied to the input terminal Q _1. Therefore, the selector 17 outputs the output data of the REG 19b to the DCF 20. The REG19b, 'so is latched, the musical tone waveform data W _01' tone waveform data W ₀₁ is filtered again, the musical sound waveform data W ₀₂ 'is (Figure 4 (c) W _02' reference) . The tone waveform data W ₀₂ ′ is supplied to the REG 19 b and the multiplier 23 in the same manner as the above-described operation. In the REG 19b, the tone waveform data W ₀₂ ′ is latched and supplied to the input terminal Q ₁ of the selector 17.

Musical sound waveform data W ₀₂ ′ supplied to one multiplier 23
Is controlled in level according to the multiplication coefficient a ₁ .
However, the multiplication coefficient a ₁ at this time is set to “1”. The musical tone waveform data W ₀₂ ″ (= W ₀₂ ′) whose level is controlled is
Latched by REG19c and REG19d. However, at this time, it is not supplied to the adder 24 via the selector 18b. Therefore, the above-mentioned musical sound waveform data W
₀₁ "is kept as it is.

Then, the selector 17, in response to the select signal S0~S2 the control unit 16 outputs, again outputs the output data of REG19b supplied to the input terminal Q ₁ to DCF29. REG19b
Since the tone waveform data W ₀₂ ′ is latched,
The tone waveform data W ₀₂ ′ is filtered to become tone waveform data W ₀₃ ′ (see FIG. 4C, W ₀₃ ′).
This musical sound waveform data W ₀₃ ′ is, like the above-described operation,
The signal is supplied to the REG 19b and the multiplier 23.

The multiplier 23 is supplied with the multiplication coefficient a ₃ from the multiplication coefficient generator 21. Therefore, the level of the tone waveform data W ₀₃ ′ supplied to the multiplier 23 is controlled in accordance with the multiplication coefficient a ₃ . Here, the level-controlled musical sound waveform data W ₀₃ ′ is set to W ₀₃ ″ (see W ₀₃ ″ in FIG. 4C).
Then, the musical tone waveform data W ₀₃ "is the musical sound waveform data W ₀₃ latched in .REG19c latched by the REG19c"
Is supplied to the adder 24 via the selector 18b. The adder 24 adds the tone waveform data W ₀₃ ″ to the output data of the REG 19 e. In this case, the tone waveform data W ₀₁ ″ is latched in the REG 19 e by the above-described operation. Is output as "tone waveform data _W01 " + tone waveform data _W03 "(FIG. 4 (c)).
W ₀₁ ″ + W ₀₃ ″). This "tone waveform data W ₀₁ " + tone waveform data W ₀₃ "is latched by the REG 19e.

Then, the selector 17 is supplied to the input terminal Q ₄ REG19d
Is output to the DCF 20 selectively. Therefore, the musical tone waveform data W ₀₂ ″ latched by the REG 19 d
(= W ₀₂ ′) is filtered again. Here, the filtered tone waveform data is referred to as W ₀₄ ′ (see FIG. 4C, W ₀₄ ′). This tone waveform data W ₀₄ ′
Is supplied to the REG 19b and the multiplier 23. In REG19b,
The tone waveform data W ₀₄ ′ is latched.

Musical sound waveform data W ₀₄ ′ supplied to one multiplier 23
In accordance with the multiplication coefficient a _4, its level is controlled, is latched into REG19c as tone waveform data W ₀₄ "(Fourth
(See (c) W ₀₄ ″.) The musical sound waveform data W ₀₄ ″ is
The signal is supplied to the adder 24 via the selector 18b. Adder 2
In step 4, the tone waveform data W ₀₄ ″ is added to the output data of the REG 19 e. In this case, “tone waveform data W ₀₁ ″ + tone waveform data W ₀₃ ″ is latched in the REG 19 e as described above. Therefore, the output data of the adder 24 is "tone waveform data _W01 " + tone waveform data _W03 "+ tone waveform data _W04 " (FIG. 4 (c) _W01 "+ _W03 " + W
₀₄ "reference). Then, this" musical tone waveform data W ₀₁ "+ tone waveform data W _03" + tone waveform data W ₀₄ "" is, REG1
It is latched and output at 9e and 19f.

In this way, the filter system 15 shown in FIG. 2 constitutes a multistage filter flow shown in FIGS. 4 (a) to 4 (g).

The multiplication coefficients a _{1 to} a ₄ output from the multiplication coefficient generator 21 described above may be constant values or those that change with time.
Also, a composite signal of both may be used.

It is obvious that techniques for various conventional envelope waveform generators can be applied as means for changing the multiplication coefficients a _{1 to} a ₄ with time. In addition, it may be further applied to operation signals of various operation elements.

Next, the control unit 16 shown in FIG.
This will be described with reference to the block diagram shown in FIG. 8 and FIG.

. Configuration of control unit 16. 7, the control unit 16 includes a timing control unit 16a and a DCF control unit 16b. FIG. 2 shows the timing control unit 16a according to the system clock φ, the time division control signal output by the system controller 13 and various operation parameters (filter flow FF, filter type TP, feedback gain FB, key-on signal KON, etc.). It outputs the selector control signals S0 to S3 and the control signals RC1 to RC6 shown in FIG. Next, the DCF control unit 16b
Is the cutoff frequency data f for DCF20, LPF / HP
An H / L signal designating which of the Fs is to be the output of the DCF 20 and a signal for controlling the multiplication coefficient generator 21 are output. DCF
The control unit 16b includes the current value fn of the cutoff frequency, the target value fd, and the target value fd
Is supplied to the interpolation speed Si.

When the discretized data is set and the target value fd and the current value fn are set in this example (fd） fn), the DCF control unit 16b sets the interpolation speed Si at regular intervals. The data between the current value fn and the target value fd is linearly interpolated in accordance with the change speed according to the value of. This data is the current value fn
From the DCF 20 to the target value fd. When the cutoff frequency f reaches the target value fd, the DCF control unit 16b outputs an interrupt signal Int corresponding to each of the filter units FU1 to FU4 to the control system 13, as described above.

Further, a method of generating the cutoff frequency f of the DCF control unit 16b will be described with reference to a block diagram shown in FIG.

. Configuration of DCF controller 16b. In this figure, reference numeral 30 denotes a parameter writing control unit,
According to the filter designation number n, the target value fd, the current value fn,
Select the interpolation speed Si at predetermined timing with the selectors 31a, 32a, 33a.
Output to

Reference numeral 31 denotes a register having four cells, and circulates data in each cell at a predetermined timing via the selector 31a (counterclockwise with respect to the drawing). Further, the selector 31a writes either the output data from the register 31 or the target value fd to the leftmost cell of the register 31 according to the select signal S4. Also, register 32 and selector
32a, the register 33, and the selector 33a have the same configuration. This means that the filter system 15 forms a multi-stage filter flow by time division as described above (four stages in this example), and supplies a cut-off frequency f divided into four to one DCF 20. That's why. That is,
This is because, when filtering one musical sound waveform data, it is necessary to supply the cutoff frequency f to each of the filters FU1 to FU4 as shown in FIGS.

The data of the rightmost cell of the register 31 is supplied to the selector 31a and the input terminal A of the subtractor 34 and the input terminal A of the comparator 35. Also register
The data of the rightmost cell of 32 is supplied to the input terminal B of the subtractor 34 and the selector 32a. The data of the rightmost cell of the register 33 is supplied to the input terminal B of the divider 36. The output of the selector 37a is supplied to the register 37. This register 37 is composed of four stages of cells in the same manner as the registers 31 to 33 described above. Data is written while circulating through the cells, and data written in the rightmost cell is input to the comparator 35. End B and adder 38
Supplied to

Next, the subtracter 34 obtains the level difference D by subtracting the current value fn from the target value fd, and supplies the result to the input terminal A of the divider 36. The most significant bit (MSB) of the above result is supplied to the select terminal of the selector 39. Also, the divider
36 calculates the level difference D between the target value fd and the current value fn by the interpolation speed Si.
Then, an increment Rate per unit time is obtained by dividing by the formula (1) and is supplied to the AND circuit 40. The AND circuit 40 takes the logical product of the inverted output of the selector 39 and the above-mentioned increment Rate, and supplies the result to the adder 38. The adder 38 adds the result of the logical product and the output data of the register 37, and supplies the result to the selector 37a. The selector 37a outputs a start signal
The current value fn or the output of the adder 38 is written to the circulating cells of the register 37 in accordance with the clock timing of START P. The data of the cell on the right side of the register 37 is output as the cutoff frequency f. The comparator 35 compares the target value fd with the output data (cutoff frequency f) of the register 37 described above, and determines that the cutoff frequency f is equal to the target value.
If it is equal to or more than fd, it outputs "0" to the selector 39, and if it has not reached the target value fd, it outputs "1".

Next, the selector 39 supplies the output data of the comparator 35 to the shift register 41 according to the most significant bit MSB of the output data of the subtractor 34. The shift register 41 is composed of four-stage cells. At a predetermined timing (timing clock Int Shift), the shift register 41 shifts the data written in the cell to the right side in the drawing and shifts the selector 39 to the right.
Is written to the leftmost cell. When the data corresponding to “1” of the filter designation number n is shifted to the rightmost cell of the register 41, the data of each cell is output to the latch circuit. At a predetermined timing (timing clock Int Latch), the latch circuit 42
While latching the data of the shift register 41, the first
Output to the system controller 13 shown in the figure.

Further, 43 is a timing generator, the system clock phi, the synchronous clock phi _t, and a start signal START
Depending on the timing clock Int Shi of various registers
It outputs a start signal START P in the calculation of ft, Int Latch, f · SEL, LATCH1 to LATCH4, and cutoff frequency f. The timing clocks Int Shift and I
The nt LATCH is supplied to the shift register 41 and the latch circuit 42, respectively. The timings LATCH1 to LATCH4 are
1, 32, 33 and 37.

The movement of data in a cell in each of the registers 31, 32, 33, and 37 and the shift register 41 is performed in synchronization with the various timing clocks. For example, as shown in FIG.
DCF control unit 16b, the cut-off frequency f ₁ for the first stage DCF20 (filter units FU1 shown in FIG. 4) is calculated, the cutoff frequency f ₁ for the filter unit FU2
Is output.

Next, regarding the operation of the electronic musical instrument having the above-described configuration,
This will be described with reference to the flowcharts shown in FIGS. 9, 10, and 11.

B. Operation of the embodiment. FIG. 9 is a flowchart showing the operation of the system controller during a performance. This routine is a main routine started when the power is turned on to the system controller. When this routine is started, first,
In step S101, initialization is performed. Next, the process proceeds to step S102, where key processing is performed.

The key processing routine is shown in FIG. In the key processing, first, in step S201, it is detected whether the keyboard is pressed or released, and the process proceeds to step S202. In step S202, it is determined whether the keyboard has been pressed. If the result of the determination in step S202 is “YES”,
Proceed to step S203. In step S203, the key code KC
And key-on speed KV. Next, step S204
And the filter designation number n is set to “1”. Then, the process proceeds to step S205, where the filter designation number n is changed to the eighth.
It is supplied to the parameter writing control unit 30 shown in the figure. Next, S2
At 06, an interpolation speed Si corresponding to the key-on speed KV is determined. The interpolation speed Si may be obtained by calculation, or a table of the interpolation speed Si may be created in advance and read from this table. Here, the interpolation rate Si to filter specified number n ₁ and Si _1.

Next, in step S207, DC
Fd ₁ as the target value fd of the cutoff frequency f of F20, the current value
The fn ₁ and the interpolation speed Si ₁ are supplied to the parameter writing control unit 30 as fn. The parameter writing control unit 30 writes the target value fd ₁ , the current value fn _1, and the interpolation speed Si ₁ into predetermined cells of the registers 31, 32, 33 according to the filter designation number n. Next, the process proceeds to step S208, where "1" is added to the filter designation number n, and the result is set to "2". Then, in step S209, it is determined whether or not the filter designation number n has reached “5”. In this embodiment, since the time division is performed in four stages as described above, the tone designation information is transmitted to all of the DCFs 20 (filter units FU1 to FU4) corresponding to each time division stage. This is to determine whether the setting has been made. If the determination in step S209 is "NO", the flow returns to step S205.
Then, again, step S205, step S206, step
Execute S207 and step S208. And step
The above processing is performed until the result of the determination in S209 becomes "YES", that is, until predetermined musical tone designation information is written in all the cells of the registers 31, 32, and 33. Here, the target value fd fd ₃ cutoff frequency f ₃ to the filter unit FU 3, the current value fn and fn _3, likewise the target value fd of the cut-off frequency f ₄ for the filter unit FU4 fd _4,
The current value fn and fn _4.

Then, when the result of the determination in step S209 is “YES”, the flow proceeds to the next step S210. In this step S210,
The key code KC, the key-on speed KV, and the key-on signal KON are supplied to the musical tone waveform generator 14. Next, the process proceeds to step S211 to supply a start signal START to the timing generator 43 shown in FIG. 8, and returns to the main routine.

On the other hand, the musical tone waveform generator 14 generates predetermined musical tone waveform data according to the key code KC, key-on speed KV, and key-on signal KON supplied from the system controller 13, and supplies the musical tone waveform data to the filter system 15. The DCF controller to which the start signal START was supplied
16b, according to various timing clocks output by the timing generator 43, while sequentially circulating the cells of the registers 31, 32, and 33, using the musical tone designation information moved to the rightmost cell, according to the value of the interpolation speed Si. According to the change speed, data (cutoff frequency f) between the current value fn and the target value fd is calculated. Hereinafter, the operation of the above-described DCF control unit 16b will be described in detail.

Each register 31, 32, 33, the target value fd ₁ ~fd ₄ written to each cell as described above, the current value fn ₁ to fn ₄ and interpolation speed Si ₁ ~Si ₄ is orbiting at a predetermined timing And the data moved to the rightmost cell is output. in this case,
Each register may, for example, when a state shown in FIG. 8, first, input terminal A of the target value fd ₁ and the current value from the register 32 fn ₁ and are each subtractor 34 from the register 31, B Supplied to Subtractor 34, the current value fn ₁ from the target value fd ₁ is subtracted (in this case, and fd _1> fn _1), it is supplied to the input terminal A of the divider 36 as a level difference D.

Next, the divider 36 divides the level difference D by the interpolation speed Si ₁ from the register 33, and divides the calculation result by the increment value R
ate is supplied to the AND circuit 40.

On the other hand, the comparator 35 compares the target value fd ₁ with the output data of the register 37 (final value in the previous operation, current value fn ₁ ), and outputs the comparison result to the selector 39. The selector 39 supplies the comparison result of the comparator 35 to the AND circuit 40 and the shift register 41 according to the most significant bit MSB of the output data of the subtractor 34. In this case, the target value fd ₁ becomes the current value fn ₁
Therefore, the AND circuit 40 is opened and the divider 36
Is supplied to the adder 38. The comparison result is written in the shift register 41.

Then, in the adder 38, the increment value Rate and the output data (current value fn ₁ ) of the register 37 are added and supplied to the selector 37a. The selector 37a receives the start signal START described above.
The addition result output from the adder 38 is selectively output to the register 37 according to P. The register 37 shifts the data of each cell to the right at a predetermined timing, and writes the output data from the adder 38 to the leftmost cell. The written data is the cutoff frequency f _1.

Similarly, the registers 31, 32, and 33 sequentially rotate each data counterclockwise by one cell. The register 31 sequentially outputs the target values fd ₂ , fd ₃ and the current fd ₄ . Further, the register 32 sequentially outputs the current values fn ₂ , fn ₃ and fn ₄ .
Then, the register 33 sequentially stores the interpolation speeds Si ₂ , Si ₃ and Si
Outputs ₄ . Then, each time the data of each cell is output, the above-described operation is performed, and the output data from the adder 37a is written to each cell of the register 37. Here, the cut-off frequency f determined for each filter unit FU1~FU4 and f _1, f _2, f ₃ and f _4, respectively (see FIG. 8 register 37). The cutoff frequencies f _{1 to} f ₄ are
In synchronization with the timing shown in FIG. 6, the DCFs are sequentially supplied to the DCFs 20 (see the filter units FU1 to FU4 in FIG. 4) in each of the time-divided stages. As a result, the musical sound waveform data passing through the DCF 20 changes variously over time. The musical tone waveform data is supplied to the level control unit 6 and output as a musical tone signal. Operation described above, the cutoff frequency f ₁ ~f ₄ is repeated until a target value fd ₁ ~fd _4, each time a new cut-off frequency f ₁ ~f ₄ is computed, is supplied to the DCF20 You.

On the other hand, if the result of the determination in step S202 is "N
If “O”, that is, if the key-on signal KON is not detected, the process proceeds to step S212. In step 212, it is determined with reference to the key-off signal KOFF whether the keyboard has been released. If the result of the determination in step S212 is "NO", that is, if the keyboard is not operated, the process returns to the main routine. On the other hand, if the result of the determination in step S212 is “YES”, then step S21
Proceed to 3. In this step S213, the key code KC and the key-off speed KOFFV are fetched. Next, the process proceeds to step S214, where the filter designation number n is set to “1”. Then, the process proceeds to step S215, where the filter designation number n is supplied to the parameter writing control unit 30. Next, in S216, an interpolation speed Si corresponding to the key-off speed KOFFV is obtained from the key-off speed KOFFV (S
i = Si ₁ ). Next, in step S217, the target value fd of the cutoff frequency of the DCF
d ₁ , fn ₁ as the current value fn and the interpolation speed Si ₁ are supplied to the parameter writing control unit 30. Parameter writing control unit 30
Writes the target value fd ₁ , current value fn _1, and interpolation speed Si ₁ into predetermined cells of the registers 31, 32, 33 according to the filter designation number n. Next, the process proceeds to step S218, where "1" is added to the filter designation number n, and n is set to "2". Then, in a step S219, it is determined whether or not the filter designation number n has reached “5”. In this case, since the filter designation number n is “2”, this step
The determination result in S219 is "NO", and the process returns to step S215. Then, again, step S215, the step S216, step S217 and step S218 is executed, fd _2, Si ₂ parameters writing control as fn ₂ and interpolation speed Si as the current value fn as a target value fd of the cut-off frequency f ₂ It is supplied to the unit 30. Until the determination in step S219 becomes "YES", the processing is performed, for each loop, each target value fd _3, the current value fn _3, interpolation speed Si ₃ and the target value fd _4, the current value fn ₄ , the interpolation speed Si ₄ is supplied to the parameter writing control unit 30.

Then, when the result of the determination in step S219 is “YES”, the flow proceeds to the next step S220. In this step S220,
Key-off processing is performed. The musical tone waveform generator 14 generates musical tone waveform data based on the key-off process, and supplies the musical tone waveform data to the filter system 15. Next, in step S221, a start signal START is supplied to the timing generator 43 of the filter system 15. This start signal START, DCF control unit 16b is activated, similarly to the routine in the key-on processing of the above-described key processing, the cutoff frequency f ₁ ~f ₄ is calculated. And
Cut-off frequency f ₁ ~f ₄ are sequentially supplied to the DCF20, DCF
The musical tone waveform data filtered to 20 is supplied to the level control unit 6 and output as a musical tone signal. Then, the process returns to the main routine.

The above-described calculation is automatically performed independently of the system controller 13 and repeatedly performed until the supply of the musical tone waveform data is completed.

On the other hand, when returning from each subroutine to the main routine,
Proceeding to step S103, setting of various coefficients and display processing are performed, and the process returns to step S101 again. Then, step S10
1. Steps S102 and S103 are executed.

Further, the DCF control unit 16b performs any one of the cutoff frequencies f
Reaches the target value fd, the corresponding cell of the shift register 41 is set. Next, the contents of the shift register 41 are:
The latch is latched by the latch circuit 42 every time the calculation for four stages is completed.

Then, the contents of the latch circuit 42, an interrupt signal Int ₁ -In
It is supplied to the system controller 13 as t _4.

On the other hand, the system controller 13 is interrupted at regular intervals, and when the interrupt occurs, the flowchart shown in FIG. 11 is executed. Hereinafter, this interrupt processing will be described.

When the above interrupt occurs, first, when step S301 is executed, in this step S301, the key-on signal KON is detected, and it is determined whether or not the keyboard is pressed. If the result of the determination in step S301 is "YES", that is, if the key is pressed, the process proceeds to step S302. Hereinafter, the interrupt processing at the time of key depression will be described.

This step S302 the interrupt signal Int ₁ is whether or not it is set is determined. If the result of the determination in step S302 is “YES”, the flow proceeds to step S303.
In this step S303, the filter designation number n is set to “1”.
And proceed to the next step S304. In step S304, the target value fd ₁ , the current value fn ₁ and the interpolation speed Si ₁ of the new cutoff frequency f are supplied to the parameter writing control unit 30. In addition, the parameter writing control unit
Supply ₁

By the above-described processing, the parameter writing control unit 30 writes the target value fd ₁ , the current value fn ₁ and the interpolation speed Si ₁ into predetermined cells of the registers 31, 32, and 33 according to the filter designation number n, reset cell of the first-stage latch circuit 42 (FU1) by a reset signal IR _1.

On the other hand, if the determination result in step S302 is “NO” and after the processing in step S304 described above, step S3
Proceeding to 05, it is determined whether or not the interrupt signal Int ₂ has been set. If the determination result of step S305 is “YES”, steps S306 and S307
, The filter designation number n is set to “2”, the target value fd _{2 of the} new cutoff frequency f, the current value fn ₂ , the interpolation speed
The Si ₂ and the reset signal IR ₂ are supplied to the parameter writing control unit 30.

By the process of step S307, the parameter writing control unit 30 sets the target value fd ₂ , the current value fn ₂ and the interpolation speed Si ₂ to each of the registers 31, 32, writes to a given cell 33, and resets the cell of the second-stage latch circuit 42 (FU2) by the reset signal IR _2.

If the determination result in step S305 is “NO” and after the processing in step S307 described above, step S3
Proceeds to 08, whether or not an interrupt signal Int ₃ is set is determined. If the determination result of step S308 is “YES”, step S309 and step S310
, The filter designation number n is set to “3”, the target value fd _{3 of the} new cutoff frequency f, the current value fn ₃ , the interpolation speed
The Si ₃ and the reset signal IR ₃ are supplied to the parameter writing control unit 30.

By the processing in step S310, the parameter writing control unit 30 determines that the target value fd ₃ , the current value fn ₃ and the interpolation speed Si
₃ is assigned to each register 31, 32, _{3 according} to the filter designation number n.
3 and the reset signal IR ₂
Resets the cells of the third stage (FU3) of the latch circuit 42.

If the determination result in step S308 is “NO” and after the processing in step S310 described above, step S3
Proceeding to 11, it is determined whether or not the interrupt signal Int ₄ has been set. If the determination result of step S311 is “YES”, step S312 and step S313
, The filter designation number n is set to “4”, the target value fd _{4 of the} new cutoff frequency f, the current value fn ₄ , the interpolation speed
The Si ₄ and the reset signal IR ₄ are supplied to the parameter writing control unit 30.

By the processing in step S313, the parameter writing control unit 30 determines that the target value fd ₄ , the current value fn ₄ and the interpolation speed Si
₄ is assigned to each register 31, 32, 3 according to the filter designation number n.
Writes to the cell of the fourth-stage 3 (FU4), and resets the fourth stage of the cell of the latch circuit 42 by a reset signal IR _2. Then, when the process of step S313 ends,
Alternatively, when the result of the determination in step S311 is “NO”, the routine is terminated and the main routine is continuously executed.

DCF control unit 16a newly, including a tone specifying information set, subsequently each interpolation speed Si ₁ ~Si each target value from the current value fn ₁ to fn ₄ at a rate of change according to the value of ₄ fd _{1 to} f
a linear interpolation between the d _4, determine the cut-off frequency f ₁ ~f _4. Then, for each stage of time division, and supplies a respective cut-off frequencies f ₁ ~f ₄ to DCF20. Therefore, the musical tone waveform data is filtered by the multi-stage filter units FU1 to FU4 until the musical tone stops, and thereafter supplied to the level control unit 6 and output as a musical tone signal.

On the other hand, if the key is released, the result of the determination in step S301 is "NO", and the flow proceeds to step S314. Hereinafter, the interrupt processing at the time of key release will be described.

In step S314, similar to step S302 described above,
Whether an interrupt signal Int ₁ is set is determined. Then, the determination result of step S314 is "YES".
In step S315 and step S316, the filter designation number n is set to “1”, and based on the key-off speed KOFFV, the cutoff frequency target value fd ₁ , current value fn ₁ , interpolation speed Si ₁ and the reset signal IR ₁ are supplied to the parameter writing control unit 30.

Hereinafter, in the same manner as the interrupt processing such as the key depression described above,
Interrupt signal Int ₂ in step S317 is determined whether being set, if the result is "YES",
In steps S318 and S319, the second stage FU
Target value fn 2 of cut-off frequency f ₂ for ₂ and current value f
d ₂ , the interpolation speed Si ₂ and the reset signal IR ₂ are supplied to the parameter writing control unit 30. Further, it has been determined whether the interrupt signal Int ₃ at step S320 is set, if the result is "YES", step S321 and in step S322, the cut-off frequency f ₃ for DCF in the third stage The target value fn ₃ , the current value fd ₃ , the interpolation speed Si _3, and the reset signal IR ₃ are supplied to the parameter writing control unit 30. Further, in step S323, the interrupt signal Int ₄
Is set or not, and if the result is “YES”, in steps S324 and S325, the target value fn ₄ of the cutoff frequency f ₄ for the fourth-stage DCF and the current value fd ₄ , Interpolation speed Si ₄ and reset signal I
R ₄ is supplied to the parameter writing control unit.

Thus, during operation for obtaining repeatedly cut-off frequency f, when the cut-off frequency f reaches the target value fd, when the key pressing, the step S316 in response to the interrupt signal Int ₁ to INT _4, One of S319, S322, and S325 is executed. Then, when any of the above processes is executed, the parameter writing control unit 30 sets the new target value fd, the current value fn, and the interpolation speed in accordance with the filter designation number n.
Si is written into predetermined cells of the registers 31, 32, and 33, and predetermined cells of the latch circuit are reset by a reset signal IR. Then, the DCF control unit 16b continues to
The current value fn ₁ is a change speed corresponding to the respective interpolation speeds Si _{1 to} Si ₄ including the newly set musical tone designation information.
Ffn ₄ , linear interpolation is performed between the respective target values fd _{1 to} fd ₄ , and data between them, that is, cutoff frequencies f _{1 to} f ₄ are obtained and supplied to the DCF 20 at a predetermined timing.

The cutoff frequency f ₁ for the filter unit FU1 obtained as described above is shown in Figure 12. In this figure, the target value of the cutoff frequency f which is set first
fd is F _1, the current value fn is F _0, the interpolation rate Si is S _1. Further, when the cut-off frequency f reaches the target value F _1, the target value fd is F ₂ to be newly set, the current value fn is F _1, interpolation speed Si is S _2. Hereinafter, similarly, the target value fd, the current value fn,
By updating the interpolation speed Si to a new value of F ₃ , F ₂ , S ₃ and F ₄ , F ₃ , S ₄ respectively, the cutoff frequency f ₁ changes with time. In this figure, the cut-off frequency F ₄ and subsequent sets the previous F ₃ as a target value fd is repeated again until the key-off signal KOFF is supplied. Similarly, at the time of key release, the target value fd is set to F ₆ and the current value f
By newly updating n to F ₅ and the interpolation speed Si to S ₆ , the cutoff frequency f ₁ for the filter unit FU1 is updated.
Changes over time as shown. Further, the cutoff frequency f for the filter units FU2, FU3, and FU4 also changes with time similarly to the above-described filter unit FU1.

Then, when the processing of step S325 is completed, or when the determination result of step S323 is “NO”, the interrupt processing routine is terminated, and the processing of the main routine is continuously performed.

In this embodiment, for example, in an actual piano, the damper returns to the string corresponding to the key when the key is released, suppressing the vibration of the string and muting the sound. However, the faster the key release speed, the more the return of the damper. String vibration is dumped quickly and rapidly.
Further, from the viewpoint of tone color change, as the key release speed is higher, the tone color change from the start of key release to the attenuation of string vibration to the silence is faster in time, and the higher frequency harmonic component is attenuated faster.
In order to realize this effect with an electronic musical instrument, it is sufficient to perform control such that the cutoff frequency f of the LPF is reduced at a speed corresponding to the key release speed.

Further, in this embodiment, the interpolation between the current value fn and the target value fd is simple linear interpolation, but an exponential curve,
Interpolation may be performed using various curves. Also,
According to the technique of the embodiment, there is obtained an advantage that not only generation of a musical tone of a piano or the like but also various timbre changes can be given.

[Effects of the Invention] As described above, according to the present invention, the filter means having a configuration in which the frequency characteristic can be easily controlled is controlled based on the filter envelope, and the larger the touch information at the time of key release, the larger the filter envelope becomes. Since the temporal change rate is controlled quickly, the tone of the generated musical tone can be variously changed by the player changing the touch at the time of key release, and as a result, the possibility of musical expression is expanded, and There is an advantage that various tone changes can be imparted to musical tones.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the configuration of one embodiment of the present invention,
FIG. 2 is a block diagram showing the configuration of the filter system of the embodiment, FIG. 3 is a block diagram showing the configuration of the DCF of the embodiment, and FIG. 4 is a filter flow constituted by the filter system of the embodiment. FIG. 5, FIG. 5 is an explanatory diagram showing an example of a multiplication coefficient output by the multiplication coefficient generator in the filter flow, FIG. 6 is an explanatory diagram for explaining the operation of the filter flow, and FIG. FIG. 8 is a block diagram showing the configuration of the DCF controller, FIGS. 9, 10, and 11 are flowcharts showing the operation of the embodiment, and FIG. FIG. 13 is an explanatory diagram for explaining the operation of the embodiment, FIG. 13 is a block diagram showing a configuration of a first conventional electronic musical instrument, and FIG. 14 is a block diagram showing a configuration of a second conventional electronic musical instrument. 11 ... keyboard part (key information generation means), 13 ... system controller, 15 ... filter system (filter means),
16: control section (filter control means), 21: multiplication coefficient generator (filter envelope generation means).

Claims (2)

(57) [Claims] 1. Key information generating means for outputting tone information including touch information at the time of key release, filter means for filtering a tone signal generated according to the tone information, and characteristics of the filter means in time Filter envelope generating means for generating a filter envelope for changing, and envelope control means for controlling a filter envelope generated by the filter envelope generating means in accordance with the touch information at the time of key release, comprising: A filter information generating means for increasing a change speed of a filter envelope generated by the filter envelope generating means as the touch information becomes larger, and a filter control for controlling a characteristic of the filter means based on the filter envelope generated by the filter envelope generating means. And means. Electronic musical instruments. 2. The filter means comprises a plurality of filters, and the filter control means controls a characteristic of at least one of the plurality of filters of the filter means by a filter generated by the filter envelope generating means. The electronic musical instrument according to claim 1, wherein the control is performed based on an envelope.