JP3139063B2 - Envelope generator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an envelope generator for controlling the volume and sound quality of musical tones generated from an electronic musical instrument or the like in response to the operation of performance operators such as a keyboard. The present invention relates to an envelope generation device capable of applying modulation according to aftertouch.

[0002]

2. Description of the Related Art Heretofore, there has been known an envelope generating apparatus used in an electronic musical instrument or the like capable of generating a musical tone corresponding to the waveform shown in FIG. This waveform shows the attack from pressing the key until the level reaches the maximum value, the decay from this maximum value to the level of the sustained sound, the sustain that is the level of the sustained sound, and the level after the key is released. This is based on an envelope composed of releases up to zero, and the sustain portion S of this envelope is periodically fluctuated. Therefore, when the sound source is driven based on this waveform, the continuous sound fluctuates periodically, and a musical tone having a slight fluctuation in the continuous sound is generated. In other words, the musical tone of a natural musical instrument, for example, a piano, has a slight fluctuation in the generated musical tone from key-on to key-off according to the pressed state of the key. Therefore,
In an electronic musical instrument, by oscillating the sustain portion S of the envelope periodically, it is possible to generate a fluctuation in a sustained sound or to generate a tremolo effect according to the strength of aftertouch, as in a natural musical instrument.

FIG. 17 shows a conventional apparatus for obtaining a waveform in which the sustain portion S is periodically changed. This device is an envelope generator 3
0, LFO 31 (or touch sensor), addition circuit 32,
And an interpolation circuit 33. The output value from the LFO 31 is added to an envelope output value output from the envelope generator 30 by an addition circuit 32. At this time, since the output from the LFO 31 is discrete, the interpolation circuit 33 interpolates between the discrete values to obtain a waveform in which the sustain portion S of the envelope fluctuates periodically as shown in the figure. Is what you can do.

[0004]

However, FIG.
In the conventional device shown in FIG.
In addition, since the addition circuit 32 and the interpolation circuit 33 are required, the configuration becomes complicated in hardware. For this reason, a device that forms an envelope by software using only a microcomputer and generates a periodic variation in the sustain portion S has been put to practical use.
However, if it is attempted to generate a periodic variation in the sustain portion using only software, it is impossible to vary the sustain portion S at a fast cycle because the processing speed of the microcomputer is limited. It has been impossible to generate a tremolo that fluctuates at a fast cycle, which approximates the fluctuation of a musical tone generated from a musical instrument.

The present invention has been made in view of such a conventional problem, and has a simple hardware configuration.
It is another object of the present invention to provide an envelope generating device capable of generating a tremolo having a fast cycle without imposing a load on software of a microcomputer.

[0006]

In order to solve the above-mentioned problems, according to the present invention, level data which is a target value of each successive step for forming an envelope waveform and rate data which indicates a change speed are predetermined. Storage means for storing the level data and the rate data of each step from the storage means in accordance with the order, and at regular intervals based on the rate data of the steps output from the output means. Accumulation, and outputs the accumulated value as an envelope output value for forming an envelope waveform corresponding to each step. When the accumulated value exceeds the level data of the step, the next step is executed. An envelope output means for instructing the output means to output level data and rate data; A modulation data output means for, the d
Accumulated value exceeds level data in envelope output means
The rate data used for the accumulation and the
Detecting means for detecting whether or not the step of the level data is a specific step;
When it is detected that is, level data of the next step
And a variable setting unit for variably setting the target value by adding the value of the modulation data to the value of the level data in the step without outputting the target value.

Further, the modulation data output means is an LFO generation means for outputting a value corresponding to a signal of a fixed period as the modulation data, or an after touch detection means for detecting an after touch when operating a performance operator. Further, the modulation data output means is configured to add a value corresponding to the after touch detected by the after touch detection means to the modulation data and output the result. Further, it is preferable that the detecting means detects a step corresponding to sustain of the envelope as the specific step.

[0008]

In the above construction, when the output means outputs, for example, level data and rate data of a step corresponding to an attack portion of an envelope waveform, accumulation is performed at regular intervals based on the rate data. The accumulated value is output as an envelope output value, and an attack portion of the envelope waveform is formed by the envelope output value. Further, when the accumulated value as the envelope output value forming the attack portion exceeds the level data value of the step, the next step, that is, the rate data of the step corresponding to the decay portion is output from the output means. Is output and a decay portion of the envelope waveform is formed in the same manner as described above.

[0009] Then, specific steps by said detecting means, for example, and this <br/> a step corresponding to the sustain is detected, the variable setting means, the next step
Level data by adding the value of the modulation data to the level data of the step without outputting a target value of those said step variably setting. Therefore, in certain steps
Performs the accumulation based on the rate data, every time the accumulated value reaches the target value, by which the target value is changed,
Continue accumulation up to the changed target value. Therefore, the change of the target value and the accumulation up to the changed target value are repeated. At this time, the accumulated value is output as an envelope output value for forming an envelope waveform, whereby the sustain portion of the envelope waveform is output. Varies periodically according to the change in the modulation data.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment in which the present invention is applied to an electronic musical instrument will be described below with reference to the drawings. That is, FIG. 1 shows the overall circuit configuration of the present embodiment. The ROM 2 includes a program for operating the microcomputer 1 and the level data from LEVEL (0) to LEVEL (5) shown in FIG. Rate data from RATE (0) to RATE (5), LFO-RAT for determining LFO change rate
E, LFO-DEPTH for determining the depth of LFO, and AFTER-DE for determining the degree of aftertouch
PTH is stored. The level data and the rate data are values corresponding to the envelope waveform shown in FIG. 3, and LEVEL (0) is the value at point A, and LEVEL
(1) Value at point B, LEVEL (2) Value at point C, LEVEL
EL (3) is the value at point D, and the value at point D is "0". RATE (0) is the rate of change from key-on to point A, that is, the rate of change, RATE (1) is the rate of change from point A to point B, RATE (2) is the rate of change from point B to point C, and RATE (3). ) Stores the change speed from point C to point D.

The RAM 3 is used for the work of the microcomputer 1, and as shown in FIG. 4, general-purpose registers A Reg and B Reg, STEP registers, LFOCOUNT registers, LFO registers, and AFTER registers are prepared. The STEP register is provided corresponding to the envelope waveform shown in FIG.
And the register A-Reg stores the level data numbers (0) to (3) corresponding to STEP stored in the STEP register.
In Reg, late data numbers (0) to (3) corresponding to the above steps are stored.

At the input terminal and the output terminal of the microcomputer 1, a signal indicating that the envelope output value has reached the level data value is output to the ARV.
From the WT, the envelope generator 5, RA
M3 and a write signal to the tone generator 6 are output.
From the RD, the envelope generator 5, the operator group 4,
A read signal is output to the RAM3 and the ROM2, and A
, The address data is transferred to the RAM 3 and the ROM 2, and the data necessary for the ROM 2, the RAM 3, the envelope generator 5, and the tone generator 6 are transferred by the D. The operator group 4 includes a keyboard and an aftertouch sensor for detecting an aftertouch, and various switches required for the electronic keyboard instrument. Then, key-on, key-off and key data (pitch) are read from the keyboard, and
Generates a tone signal based on the transferred key data and the envelope output value, and the tone signal is emitted to the outside via a tone generation circuit 7 including an amplifier and a speaker.

FIG. 5 is a circuit diagram showing the configuration of the envelope generator 5. The first RAM 9 becomes writable when WT = 0. At this time, one step corresponding to one step input from the microcomputer 1 to the input terminal I is obtained. Is stored. The level data written in the first RAM 9 is supplied from the output terminal 01 to the input terminal B of the first comparator 10, the input terminal B of the second comparator 11, and further supplied to the contact b of the switch 12. Can be

On the other hand, the second RAM 13 is in a writable state when the signal input to the input terminal WT is "0", and writes the data input to the input terminal I. The second
The clock pulse CK1 is input to the input terminal WT of the RAM 13 via the NOT circuit 15 at regular intervals, and the output terminal O of the second RAM 13 receives the input terminal A of the first comparator 10 and the adder / subtractor. Data is output to 14 input terminals A. The first comparator 10 has input terminals A, B
An output terminal EQ that outputs “1” when the input from A = B, and an output terminal A that outputs “1” when A> B
B, and an output from the output terminal EQ is provided as one input of the first OR circuit 16. The output of the output terminal A> B is input to the input terminal SUB of the adder / subtractor 14.
And one of the input terminals of the first AND circuit 17 and the second AND circuit 18. The adder / subtractor 14 has an input terminal S
When the input to the UB is "1", it functions as a subtractor, while when it is "0", it functions as an adder. The input terminal B receives the rate data from the output terminal 02 of the first RAM 9. Further, from the output terminal O of the adder / subtractor 14, an addition result or a subtraction result is input to the input terminal A of the second comparator 11 and the other terminal b of the switch 12.

The second comparator 11 has an output terminal A> that outputs "1" when the input from the input terminals A and B is A> B.
B and an output terminal B> A that outputs “1” when B> A
The output of the output terminal A> B is supplied to the second AND circuit 18, and the output of the output terminal B> A is supplied to the first AND circuit.
Circuit 17 is provided. The outputs of the AND circuits 17 and 18 are provided to a second OR circuit 19, and the output of the second OR circuit 19 is provided to the first OR circuit 16. The output of the first OR circuit 16 is input to the ARV of the microcomputer 1, and the output of the
Is driven. That is, when the output of the first OR circuit 16 is “0”, the switch 12
Side, and the output of the adder / subtractor 14 is connected to the input terminal I of the second RAM 13 via the switch 12.
Given to. Further, when the output of the first OR circuit 16 becomes “1”, the switch 12 switches to the contact “b”, so that the level data from the output terminal 01 of the first RAM 9 passes through the switch 12, The second RA
It is provided to the input terminal I of M13.

Next, the operation of this embodiment according to the above configuration will be described with reference to the flowchart shown in FIG. That is,
FIG. 6 shows a main routine, which is started by turning on a power switch (not shown) provided in the operator group 4, and first executes an initialization process (SA
1) As a result, the various registers described above are cleared. Subsequently, the control of the operator group is executed (SA2), and then the envelope control is executed (SA3). While the power switch is maintained in the ON state, the SA2 and SA3 are controlled.
Repeat the loop.

The main routine is interrupted by a timer interrupt routine shown in FIG. 7 at regular time intervals and executed to execute LFO control (SB).
1). This LFO control is executed according to the flowchart shown in FIG. 8, and the LFO COUNT register (FIG. 4)
LFO COUNT + LFO RATE is stored (SC1). Here, LFO COUNT is shown in FIG.
Is the current value of the LFO changing to a sawtooth wave, and LFO RATE is a value indicating the changing speed of the LFO stored in the ROM 2 as described with reference to FIG.

Subsequently, SIN (LFO COUNT) is stored in the LFO register (see FIG. 4) (SC2).
Accordingly, the current value of the sine waveform shown as LFO in FIG. 9 is stored in the register LFO. Therefore, the timer interrupt routine shown in FIG.
By being executed at regular intervals, the LFOCO
The UNT register contains the LFO C at the time of the interrupt.
OUT + LFO RATE is stored in the LFO register, and the SIN (LFOCOUNT) at the time of interruption is stored in the LFO register.
T) is stored.

On the other hand, the control of the operator group performed in SA2 of the main routine is executed according to the flowchart shown in FIG. 10, and firstly, is there any key turned on on the keyboard included in the operator group 4? Is determined (S
D1). If this determination is YES and there is a key that has been turned on, key-on processing is executed (SD2), and it is further determined whether there is a key that has been turned off (SD3). If this determination is YES and there is a key that has been turned off,
After the key-off process is performed (SD4), the after-process is performed (SD5). This after-processing is executed according to the flowchart shown in FIG. 11, and after-touch data detected by the after-sensor included in the operation element group 4 is temporarily set to A Reg (SE1). Thereafter, the data set in the A Reg is stored in the AFTER register shown in FIG.
E2) Therefore, the data indicating the aftertouch intensity detected by the aftersensor is stored in the AFTER register at the end of the after-processing.

The key-on processing (SD in FIG. 10)
2) is executed in accordance with the flowchart shown in FIG. 12. First, "1" is stored in the STEP register, LEVEL (0) is stored in A Reg, and RATE (0) is stored in B Reg. (SF
1). That is, since the target value A of STEP = 1 corresponding to the attack portion of the envelope shown in FIG. 3 is indicated by LEVEL (0) as shown in FIG. 2, LEVEL (0) indicating this target value A Is stored in A Reg, and RATE which is the change speed of STEP = 1 is stored.
(0) is stored in B Reg and envelope generator control (SF2) is subsequently performed.

This envelope generator control (SF2)
Is executed according to the flowchart shown in FIG.
First, the value LFO stored in the LFO register (FIG. 4) is multiplied by the LFO DEPTH stored in the ROM 2 by SC2 in FIG. 8 described above, and the value is added to the value of the level data stored in A Reg. Then, the added value is stored in A Reg (SG1). Further, the value indicating the aftertouch strength stored in the AFTER register in SE2 of FIG. 11 described above is multiplied by AFTER DEPTH stored in ROM2, and then the value is applied to A Reg in SG1. The value is added to the stored value, and the added value is stored in A Reg again (SG2). Therefore, at this point, A Reg
LEVEL (0) stored in SF1 of FIG.
In addition, (LFO × LFO DEPTH) and (AFTER ×
AFTER DEPTH) is stored, and RATE (0) is stored without changing the value of B Reg.

Next, after the contents of A Reg and B Reg are sent to the envelope generator 5 (SG3), "0" is output from the WT (SG4), whereby the first RAM 9 is in a writable state. Therefore, the level data (target value) stored in A Reg in SG3 and BR
The late data stored in the eg is written into the first RAM 9 of the envelope generator 5 shown in FIG. The level data written in the first RAM 9 is transmitted from the output terminal 01 to the input terminal B of the first comparator 10 and the second comparator 1
1 and one terminal b of the switch 12, and the late data is supplied from the output terminal 02 to the input terminal B of the adder / subtractor 14. At this time, the second RAM 13 holds the current value of the envelope as described later, and this current value is given to the input terminal A of the first comparator 10.
Therefore, when the target value is larger than the current value, as in the case where the processing in STEP = 1 where RATE is +, the relationship between the input terminals A and B in the first comparator 10 is B> A. Therefore, both output terminals EQ, A> B of the first comparator 10 are both "0".

Therefore, the SUB input of the adder / subtractor 14 becomes "0", and the adder / subtracter 14 functions as an adder. Therefore, in the adder / subtractor 14, the second RAM 13
Is added to the current value input from the input terminal A to the input terminal A based on the late data input to the input terminal B, and the addition result is output to the input terminal A of the second comparator 11 and the terminal a of the switch 12. . Then, the second comparator 11 compares the addition result input to the input terminal A with the target value of the currently executed step input to the input terminal B, and determines the addition result as the target value (LEVEL). , The output end B> A outputs “1” to the first AND circuit 17. However, the other input of the first AND circuit 17 is “0”.
Therefore, the output of the first AND circuit 17 is “0”
It is. Further, since the output of the second AND circuit 18 is “0”, the outputs of the second OR circuit 19 and the first OR circuit 16 also become “0”, and as a result, the switch 12
Keep in contact with.

That is, when the switch 12 is in contact with the contact a, the output of the adder / subtractor 14 is input to the second RAM 13 via the switch 12 and to the input terminal D of the microcomputer 1. And the second RAM
In 13, the output of the adder / subtractor 14 is written as the current value at the timing of CK1, and this current value is output to the input terminal A of the first comparator 10 and the input terminal A of the adder / subtractor 14. Therefore, when the value of RATE is +, the target value (LEVE
L)> As long as the state of the current value continues, the current value as the addition result of the adder / subtractor 14 is input to the second RAM 13 via the switch 12.

When the current value reaches the target value (LEVEL), A = B in the first comparator 10, and "1" is output from the output terminal EQ of the first comparator 10.
Then, the output of the first OR circuit 16 becomes “1”, the switch 12 becomes conductive with the contact “b”, the current level data is written in the second RAM 13, and ARV = 1. If the current value exceeds the target value due to excessive addition by the adder / subtractor 14 without A = B,
Since A> B in the second comparator 11, the second comparator A
The output of the ND circuit 18 becomes “1”, and the first and second O
The outputs of the R circuits 16 and 19 become "1", the switch 12 comes into contact with the contact "b" in the same manner as described above, the current LEVEL is written in the second RAM 13, and ARV = 1.

On the other hand, the envelope control (SA3) performed in the main routine of FIG. 6 is executed according to the flowchart shown in FIG. 14, and it is first determined whether or not ARV = 1 (SH1). If the target value has not been reached, the process returns because ARV = 0, and if the target value has been reached, ARV = 1, and the STEP that has reached the target value is any of 0-5. Is determined (SH2). In this determination, if the current step is STEP = 0, the output returns immediately since the output of the envelope waveform from attack to release has already been completed. In addition, if the determination is S
If TEP = 1, the next STEP value "2" is stored in the STEP register (FIG. 4) (SH3), and A
REG, which is level data of STEP = 2,
(1) and RATE (1), which is the late data of STEP = 2, are stored in B Reg (SH
4) Then, the envelope generator control is executed according to the flowchart of FIG. 13 described above (SH5).

In the determination of SH2, STEP =
If it is 2, the next STE is stored in the STEP register.
"3" which is the value of P is stored (SH6), LEVEL (2) which is STEP = 3 level data is stored in AReg, and RATE (2) which is late data of STEP = 2 is stored in B Reg. After storing (SH7), the envelope generator control is executed (SH5). further,
In the determination of SH2, if STEP = 3, the value of the next STEP, "4", is stored in the STEP register (SH8). Also, ST to A Reg
LEVEL (2) which is level data of EP = 4 is stored. Here, since STEP = 4 is a STEP corresponding to the sustain as shown in FIG.
After storing SUS RATE (constant) as rate data in g (SH9), the envelope generator control is executed (SH5).

In the determination of SH2, STEP =
If the answer is 4, the program proceeds to step S
SH9 and SH5 are executed while maintaining the state of TEP = 4, and the process returns. That is, from STEP = 4 to ST
It is possible to proceed to EP = 5 when the above-mentioned determination of SD3 in FIG. 10 is YES and the key-off process of SD4 is executed, and SI1 shown in FIG. 15 described later is processed.
In other words, this is a condition under which the key-off can proceed from STEP = 4 to STEP = 5.
Even if RV = 1, the state of STEP = 4 is maintained, and SH9 and SH5 of FIG. 14 are executed each time ARV = 1 (each time the target value is reached), and the SH5 is executed.
In, the envelope generator controls SG1 to SG4 shown in FIG. 13 are executed.

At this time, in SG1 of FIG.
A Reg + (LFO × LFO DEPTH) for Reg
Is stored, and the value of LFO changes periodically with a sine waveform as shown in FIG.
1, A Reg + stored in A Reg + (LFO
X LFODEPTH) fluctuates periodically. Therefore, this periodically fluctuating value is sent to the envelope generator 5 as the content of A Reg in SG3 of FIG. 13, and the envelope generator 5 sets the sent AReg value as a target value, and ARV =
Outputs 1.

That is, when STEP = 1 to 3 is completed, the state of STEP = 4 is maintained as long as the key-on state is continued, and when AV = 1, the target value is sent to the envelope generator 5; When the envelope output value reaches the target value, the operation of outputting AV = 1 from the envelope generator 5 is repeated. At this time, since the target value periodically fluctuates according to the sine waveform shown in FIG. 9 as described above, the envelope output value that reaches the periodically fluctuating target value is repeated as shown in FIG. The sustain portion S of the envelope as shown in
Has periodically varying characteristics. Moreover, since the target value is obtained by adding the value multiplied by LFODEPTH and the value multiplied by AFTER DEPTTH in SG1 and SG2 in FIG. The modulation by the LFO of the depth and the modulation by the aftertouch according to AFTER DEPTTH are applied. Therefore, when a tone is generated from the tone generation circuit 7 in accordance with the envelope waveform, the tone periodically fluctuates according to the strength of the after touch while the key-on is continued, causing a fluctuation, and the tone generated from the natural musical instrument. A tone similar to a tone can be generated.

When the key is released, the determination of SD3 in the flowchart shown in FIG. 10 becomes YES, and the key-off process is performed (SD4), and the key-off process is executed according to the flowchart shown in FIG. That is,
First, "5" is stored in the STEP register, LEVEL (3) is stored in A Reg, and B
RATE (3) is stored in Reg (SI1). That is, the target value D (= 0) of STEP = 5 corresponding to the release part of the envelope shown in FIG. 3 is indicated by LEVEL (3) as shown in FIG. LEVEL (3) is stored in A Reg and RATE which is the change speed of STEP = 5 is used.
(3) is stored in B Reg, and envelope generator control (SI2) is subsequently performed. By performing the envelope generator control, when the envelope output value reaches the target value, ARV = 1 and the determination of SH1 shown in FIG. 14 becomes YES. At this time, the state of STEP = 5 is established. From, proceed from SH2 to SH10, ST
"0" is stored in the EP register, and the apparatus enters a standby state before key-on.

[0032]

As described above, according to the present invention, level data is periodically variably set by adding periodically varying modulation data, and the variably set level data is set as a target value. The envelope output means performs accumulation at regular time intervals, and outputs the accumulated value as an envelope output value. Therefore, a tremolo having a short cycle can be generated without complicating a hardware configuration unlike a conventional apparatus requiring an interpolation circuit. Further, in terms of software, every time the envelope output value reaches the level data which is the target value, the target value may be variably set and given to the envelope output means. It is possible to form a fast-period variation in a specific portion of the envelope regardless of the speed.

Further, the envelope generating device according to the present invention is applied to an electronic musical instrument so that a value corresponding to the after-touch of an operator is added to the modulation data, or in a step corresponding to a sustain portion of the envelope,
If the target value is variably set, it is possible to generate fluctuations in the sustain portion of the generated musical tone in accordance with the strength of the after touch, thereby generating a musical tone more similar to a musical tone generated from a natural musical instrument. It becomes possible.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the overall structure of an embodiment of the present invention.

FIG. 2 is a schematic diagram showing contents of data stored in a ROM of the embodiment.

FIG. 3 is an explanatory diagram showing a relationship between an envelope waveform and each STEP of the embodiment.

FIG. 4 is a schematic diagram showing registers prepared in a RAM of the embodiment.

FIG. 5 is a circuit diagram of an envelope generator used in the embodiment.

FIG. 6 is a flowchart showing a main routine of the embodiment.

FIG. 7 is a flowchart showing a timer interrupt routine of the embodiment.

FIG. 8 is a flowchart showing the contents of LFO control in the timer interrupt routine.

FIG. 9 is a waveform chart showing a relationship between LFO COUNT and LFO of the embodiment.

FIG. 10 is a flowchart showing the contents of an operator group control executed in a main routine of the embodiment.

FIG. 11 is a flowchart showing the contents of an after process executed in SD5 of FIG. 10;

FIG. 12 is a flowchart showing the contents of a key-on process executed in SD2 of FIG. 10;

FIG. 13 is a flowchart showing the contents of envelope generator control of the embodiment.

FIG. 14 is a flowchart showing the contents of envelope control executed in SA3 of FIG. 6;

FIG. 15 is a flowchart showing the contents of a key-off process executed in SD4 of FIG. 10;

FIG. 16 is a waveform diagram of an envelope in which a sustain portion periodically fluctuates.

17 is a block circuit diagram of a conventional device for generating an envelope having the waveform shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Microcomputer 2 ROM 3 RAM 4 Operator group 5 Envelope generator 9 1st RAM 10 1st comparator 11 2nd comparator 13 2nd RAM 14 Adder / subtracter

Continuation of the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G10H 1/057 G10H 1/053

Claims (4)

(57) [Claims] 1. A storage means for storing, in a predetermined order, level data, which is a target value of each successive step for forming an envelope waveform, and rate data indicating a rate of change, from the storage means. Output means for outputting the level data and the rate data in accordance with the order; accumulating at a constant interval based on the rate data of the step outputted from the output means; and applying the accumulated value to an envelope corresponding to each step. Envelope output means for outputting as an envelope output value for forming a waveform, and instructing the output means to output the level data and rate data of the next step when the accumulated value exceeds the level data of the step. , the modulation data output means for outputting the modulated data that varies periodically, said envelope output means It had accumulated value to the level Day
Rate data used for the accumulation when data exceeds
Detection means for detecting whether or not the step of the level data is a specific step ; and when the detection means detects that the step is the specific step , the level data of the next step is not output. To
Variable setting means for variably setting the target value by adding the value of the modulation data to the level data value of the step. 2. The modulation data output means outputs a value corresponding to a waveform of a fixed period as the modulation data.
2. The envelope generator according to claim 1, wherein the envelope generator is an O generator. 3. A performance control, and aftertouch detection means for detecting aftertouch when the performance control is operated, wherein the modulation data output means detects an aftertouch detected by the aftertouch detection means. 2. The envelope generator according to claim 1, wherein a value corresponding to the added value is added to the modulation data and output. 4. The envelope generating apparatus according to claim 1, wherein said detecting means detects a step corresponding to the sustain of the envelope as said specific step.