JP2967787B2 - Tone generator - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tone generator suitable for an electronic musical instrument.

[Prior Art] Conventionally, attack,
A device that generates an envelope waveform composed of a plurality of states such as decay is known (for example, Japanese Patent Publication No. 63-3907).
No. 2).

However, in the conventional tone generator, if the key-off operation is performed extremely quickly before the envelope waveform sufficiently rises, there is a disadvantage that the envelope waveform starts to be attenuated without an attack feeling.

Japanese Patent Application Laid-Open No. 53-25416 discloses an apparatus for generating an envelope waveform signal in an electronic musical instrument, wherein a key is turned off before the waveform level of the envelope reaches a predetermined attack level, and It is described that a different attenuation waveform is generated when the key is turned off after the attack level is reached.

However, in this method, attention is paid only to a case where a key is turned off during an attack, and an attenuation waveform is made different only depending on whether or not a predetermined attack level is reached. It has just been eliminated.

Japanese Patent Application Laid-Open No. 2-48699 discloses a technique for controlling an envelope waveform such that when a key-off timing is within a predetermined period, the timing of performing a key-off process is delayed until the predetermined period elapses. Is described.

However, in this technique, the key-off processing is simply delayed according to the timing of the key-off, so that the key-off processing must be monotonous.

As described above, in the U.S.A., the shape of the envelope cannot be variously controlled in accordance with various key-off timings.

[Problems to be Solved by the Invention] In view of the problems of the related art, an object of the present invention is to have a sufficient attack feeling even when the key-off timing is extremely early, and to respond to various key-off timings. It is an object of the present invention to provide a tone generator capable of controlling the shape of the envelope in various ways.

Means for Solving the Problems To achieve the above object, according to the present invention, there is provided an envelope waveform signal forming means for forming an envelope waveform signal, and a tone signal generating means for generating a tone signal using the envelope waveform signal. A specific position setting means for arbitrarily setting a specific position on the envelope waveform; and when a key-off instruction is given, (a) when the key-off occurs, the musical sound signal generating means (B) when the position on the envelope waveform at the key-off timing is before the specific position, the envelope waveform signal formed by the envelope waveform signal forming means is used for the key-off process. Executes a key-off process in the envelope waveform signal forming means until a specific position is reached. Without performing the key-off process in the envelope waveform signal forming means when the envelope waveform signal formed by the envelope waveform signal forming means reaches the specific position; (c) performing the key-off processing on the envelope waveform at the key-off timing; When the position is located after the specific position, the control unit causes the envelope waveform signal forming unit to execute a key-off process when the key-off occurs.

In a preferred embodiment of the present invention, the specific position setting means arbitrarily sets first and second specific positions on an envelope waveform, and the control means sets the key-off timing to the first specific position. When the key-off timing is between the first specific position and the second specific position, the key-off process in the envelope waveform signal forming means is delayed when the key-off timing is between the first specific position and the second specific position.
The attenuation characteristic of the envelope waveform in the key-off process in the envelope waveform signal forming means differs between when the envelope is after the specific position.

In an embodiment described later, the envelope waveform signal forming means corresponds to the CPU 10 and the flow shown in FIGS. 5 to 7, the tone signal generating means is provided in the tone generator circuit 16, and the specific position setting means is provided in the EG.
The setting switch 14 corresponds to the control means, and the control means corresponds to the CPU 10.

[Operation] According to the above configuration, when the position on the envelope waveform at the key-off timing is before the specific position, the key-off process in the envelope waveform signal forming means is delayed, so that the key-off timing is too early. In this case, an envelope waveform having a sufficient attack feeling can be generated.

Further, the key-off process is instructed to the tone signal generating means at the time of the key-off, and the following effects can be obtained by combining these and the configurations.
That is, in the present invention, the control to the tone signal generating means and the control to the envelope waveform signal forming means when the key is turned off are independent. Stop sounding is instructed. On the other hand, for the envelope waveform signal forming means,
If the position on the envelope waveform at the key-off timing is before the specific position, the key-off process in the envelope waveform signal forming means is delayed.

As a result, the key-off process is delayed for the envelope under the above condition, but the key-off process is performed at the time of key-off for other parameters (for example, tone, effect, etc.) even when the key-off process for the envelope is delayed. Can be executed.

[Effect] Therefore, according to the present invention, even when the key-off timing is too early, an envelope having a sufficient attack feeling can be generated, and the envelope shape can be made more versatile in accordance with the key-off timing. be able to. In addition, even if the key-off process for the envelope is delayed, the key-off process can be executed as needed when the key-off process is performed on the envelope other than the envelope, so that a wider variety of musical sounds can be generated.

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

FIG. 1 shows a hardware configuration of an electronic musical instrument according to an embodiment of the present invention.

The electronic musical instrument shown in FIG. 1 is configured to control the entire operation using a central processing unit (CPU) 10. CP
U10 has a read only memory (ROM) 11, a random access memory (RAM) 12, a key detection circuit 13, an EG setting switch group 14, and other switches via a bidirectional bus line BUS.
15 and a tone generator circuit 16 are connected. In addition, CPU1
Timer circuit 17 is connected to 0 via signal line L,
A keyboard circuit 18 is connected to the key detection circuit 13 and a tone generator circuit 16
Is connected to a sound system 19.

The ROM 11 has a program area and a parameter area. The program area stores various control programs such as a main routine process corresponding to the flowcharts shown in FIGS. 2 to 7 and a timer interrupt process. The envelope waveform of the musical tone generated in this electronic musical instrument has states such as attack, decay, hold, and release or sustain, as shown in FIGS. In the parameter area, rate data indicating the slope of each state (excluding the hold state) of the envelope waveform and level data indicating the target (final) level are stored.
This is stored as a table for each tone.

The following groups of registers are set in the RAM 12 to temporarily store various data generated when the CPU 10 executes the control program. In the following, registers and the like and their contents are represented by the same label. Also, i (= 0 to 7) is a state number, for example, state 0 is an attack state, state 1
Represents a decay state. j (= 0 to 15) is a sounding channel number.

Li: Target level of state i 0 to 95.25 (0.75 steps, 7 bits) Ri: Rate of state i 0 to 95.25 (0.75 steps, 7 bits) RR: Release rate 0 to 95.25 (0.75 steps, 7 bits) SUSR: Sustain Rate 0 to 95.25 (0.75 steps, 7 bits) EGj: Current envelope level of channel j 0 to 95.25 (0.75 steps, 7 bits) INTj: Initial touch of channel j 0 to 127 (7 bits) KCDj: Sound assignment to channel j Key code MP: Mask point 0-7 (3 bits) DP: Decay point 0-7 (3 bits) HP: Hold point 0-7 (3 bits) SUSON: Sustain flag 1: Sustain on, 0: Sustain off SYNM: Synth flag 1: Synth mode, 0: Normal mode DPINH: DP inhibit flag 1: DP inhibit, 0: DP enable HOLDj: Channel j hole KONj: Key-on flag of channel j 1: During key-on KOFFj: Key-off flag of channel j 1: End of envelope waveform formation The key detection circuit 13 detects the operation state of each key (key) on the keyboard 18 and Key information indicating key press, key release, and key touch (initial touch) for each key is generated.

The EG setting switch group 14 includes a sustain on / off switch, a synth mode setting switch, a DP inhibit switch, and the like, and generates switch information indicating an on / off or setting state of each of these switches.

Other switch groups 15 include a tone selection switch,
A volume setting switch and various effect switches are provided.

The tone generator circuit 16 includes an on / off or set state of the EG setting switch group 14 and other switch groups 15, and a keyboard.
A tone signal is formed based on envelope level information EGj sent from the CPU 10 in response to the operation 18 and tone control information such as a note on / off command, key code information KCDj, and initial touch information INTj. This tone signal is supplied to the sound system 19. Here, the tone generator 16 is formed with 16 time-division sounding channels represented by numbers j (= 0 to 15), and this electronic musical instrument can simultaneously generate 16 musical tones.

The sound system 19 converts a tone signal supplied from the sound source circuit 16 into sound and emits the sound.

Next, the operation of the CPU 10 in the electronic musical instrument of FIG. 1 will be described with reference to the flowcharts of FIGS.

When a power source (not shown) is turned on in the electronic musical instrument of FIG. 1, the CPU 10 starts operating according to a control program stored in the ROM 11. First, the processing shown in the main routine after step 100 in FIG. 2 is executed, and at the same time, the timer interrupt processing shown in FIGS. 5A and 5B is executed.

Referring to FIG. 2, first, in step 201, a target level register L0 for each state set in the RAM 12 is set.
~ L7 and rate registers R0 ~ R7, release rate register RR, sustain rate register SUSR, envelope level registers EG0 ~ GE15 for each sounding channel, initial touch registers INT0 ~ INT15, key code registers KCD0 ~ KCD15, key on flags KON0 ~ KON15 And hold flags HOLD0 to HOLD15, mask point register M
P, Decay point register DP, Hold point register HP, Sustain flag SUSON, Synth flag SYN
Initial settings such as clearing the M and DP inhibit flags DPINH and setting the key-off flags KOFF0 to KOFF15 of each sounding channel to 1 are performed. Thereafter, a circulating process including a key pressing process in step 202, an EG setting process in step 203, and other processes in step 204 is executed.

FIG. 3 shows the key pressing process in FIG. 2 (step 202).
The details are shown below.

Referring to FIG. 3, in step 301, the key detection circuit 13
It is determined whether or not a key state change due to a key press on the keyboard 18 has occurred (there is a key-on event) based on the output of. If there is a key-on event, a tone channel (key code) corresponding to the key in which the on-event occurred is assigned in step 302, and a key-on flag KONj of the assigned tone channel j is set to 1 in step 303. Then, the key code and the initial touch data of the key are stored in the key code register KCDj and the initial touch register INTj, respectively. In step 304, a note-on (sound generation start) command is issued to the j channel of the tone generator circuit 16, and the key code KCDj And initial touch data
After transmitting INTj, the process proceeds to step 305. As a result, the tone generator 16 starts a tone generation process based on the key code KCDj, the initial touch data INTj, and the envelope level data EGj described later.

On the other hand, if the determination in step 301 is “NO”, that is, if no key-on event has occurred, steps 302 to 3
Skip step 04 and skip directly from step 301 to step 3
Proceed to 05.

In step 305, the presence or absence of a key release operation (key off event) on the keyboard 18 is determined from the output of the key detection circuit 13. If there is a key-off event, a search is made in step 306 for a sound channel to which a key code corresponding to the key having the key-off event is assigned. If the corresponding channel j is found, the process branches from the next step 307 to step 308 to reset the key-on flag KONj of the corresponding channel j.
After transmitting a note-off (sound generation stop) command to the corresponding channel j, the key pressing process is terminated and the process returns to the main process (step 203 in FIG. 2). As a result, the tone generator 16 performs a tone signal formation process after the key-off in the corresponding channel j.

On the other hand, if the determination in step 307 is "NO", that is, if no sounding channel to which the same key code as the key that has been turned off is assigned is found, step 308 is executed.
Steps 307 to 309 are skipped, and the key depression processing is terminated as it is from step 307, and the main processing (step 20 in FIG. 2) is performed.
Return to 3).

If the determination in step 305 is “NO”, that is, if no key-off event has occurred, step 30
The processing of steps 6 to 309 is skipped, the key depression processing is terminated as it is from step 305, and the main processing (step 20 in FIG. 2) is performed.
Return to 3).

FIG. 4 shows the EG setting process (step 20) in FIG.
Details of 3) are shown.

In this EG setting process, the CPU 10 reads the setting state of each switch constituting the EG setting switch group 14, and stores a parameter corresponding to the setting state in a corresponding register in the RAM 12. For example, the target level L0 of each state
L7, the level change rate R0 to R7 of each state, the release rate RR, and the sustain rate SUSR correspond to the data read from the table in the ROM 11 corresponding to the tone selected by the tone selection switch. Store in L7, R0-R7, RR and SUSR. Also,
Mask Point MP, Decay Point DP, Hold Point HP, Sustain On / Off SUSON, Synth Mode On / Off SYNM, and DP Inhibit On / Off DPINH
Are created based on the state of each setting switch in the EG setting switch group 14, and are stored in the corresponding registers MP, DP, and HP, and the flags SUSON, SYNM, and DPINH.

When a clock having a fixed period (for example, 50 .mu.S) is input from the timer 17 via the signal line L, the CPU 10 executes a timer interrupt process shown in FIGS. Here, the envelope waveform forming process for one sounding channel represented by the channel number j is executed by one timer interrupt process.

Referring to FIG. 5A, in step 501, it is determined whether or not this timer interrupt processing is the first interrupt processing for the channel after the channel j is assigned as a sounding channel. If it is the first interrupt processing, the attack rate R0 is set to the maximum value (95.2
5) is determined. If it is the maximum value, the state number i is set to 1 in step 503, the envelope level EGj is set to the target level L0 of the attack state (i = 0), and the process proceeds to step 505. In this case, the envelope waveform has an extremely steep attack waveform in which the initial value becomes the attack target value L0 and the attack state ends instantly. On the other hand, if the attack rate R0 is not the maximum value, the state number i is set to 0 in step 504, and the envelope level EGj is set to the maximum value of 1
After setting the value to / 2 (47.25), the process proceeds to step 505. In this case, the initial value of the envelope waveform is 47.25,
From here, the attack state is started. Next, when the key-off flag KOFFj is reset in step 505, the process proceeds to step 551 (FIG. 5B).

If the result of the determination in step 501 is “NO”, that is, if this interrupt processing is the second or subsequent time for the channel after the tone is assigned to the j channel by the key-on event, the processing proceeds to step 511.

In step 511, the key-off flag KOFFj is checked. The flag KOFFj becomes 1 when the formation of the envelope waveform signal is completed (see step 615 in FIG. 6 and step 707 in FIG. 7). Therefore, in this case, the process directly proceeds from step 511 to step 551 (FIG. 5B) without performing any further processing relating to the envelope.

If KOFFj = 0 in step 511, the key-on flag KONj is checked in step 512. If the key is ON (KONj = 1), the hold flag HOLDj is checked in the following step 513. If the flag HOLDj is 0, a subroutine (6th
(FIG. 5) to increase or decrease the envelope level EGj at the rate Ri of the current state i, and then proceed to step 551 (FIG. 5B).

On the other hand, if the determination result of step 513 is HOLDj = 1,
In step 521, the synth mode flag SYNM is checked. If the synth mode is SYNM (SYNM = 1), step 522 is further executed.
Inspects the DP inhibit flag DPINH. And D
If P inhibit mode (DPINH = 1), step
At step 523, the state number i is jumped (state jump) to DP + 1 which is the next state of the state in which the decay point DP is set, and at step 524, the hold flag HOLDj is reset.
After executing the envelope level increasing / decreasing process of the subroutine (FIG. 6), the process proceeds to step 551 (FIG. 5B). In the case of going through the processing of steps 521 to 524, DP <
If it is HP, by the state jump processing of the step 523, the state number DP +
The waveform from 1 to HP is repeated.

If the determination result of step 521 is a normal mode (SYNM
= 0), and the determination result of step 522 is DP
If it is enabled (DPINH = 0), the process proceeds from these steps 521 or 522 to step 525, where the tone generator circuit 1
After sending the envelope level data EGj to 6, the process proceeds to step 551 (FIG. 5B).

Referring to FIG. 6, in step 601, the magnitude of the envelope level EGj and the target level Li of the current state i are compared to determine whether the current slope of the envelope waveform is positive or negative. If the gradient is positive (EGj <Li), the rate Ri is added to the level EGj in step 602; if negative (EGj ≧ Li), the rate Ri is subtracted from the level EGj in step 603. At 605, it is determined whether or not the envelope level EGj has reached the target level Li. If the target level Li has not been reached, step 606
Or 607 to the tone generator circuit 16 at envelope level data E
After sending Gj, the original routine (step 55 in FIG.
Return to 1).

On the other hand, if the target level Li has been reached, the process proceeds to step 609, where the envelope level EGj is set to the target level Li, and in step 610, it is determined whether or not the current state i is the state in which the hold point HP is set. judge. If the state is a state where the hold point HP is set (i = HP), the hold flag HOLDj is set in step 611; otherwise, the state number i is incremented in step 612, and the sound source is generated in step 613. Circuit 1
The envelope level data EGj is sent to 6, and at step 614 it is determined whether or not the state number i has reached 8. In this electronic musical instrument, the number of envelope states is set to eight (0 to 7). Therefore, if the state number i has reached 8, it means that the envelope waveform forming process has been completed. in this case,
After setting the key-off flag KOFFj in step 615,
The routine returns to the original routine (step 551 in FIG. 5B). If the state number i has not reached 8, the routine returns from step 614 to the original routine (step 551 in FIG. 5B).

Returning to FIG. 5A, if the determination in step 512 is that the key-on flag KONj = 0, this means that the key assigned to the channel j on the keyboard 18 is released (key-off).
(Step 308 in FIG. 2). In this case, post-key-off processing shown in FIG. 5B is executed.

Referring to FIG. 5B, in step 530, the hold flag HOLDj is cleared, and in step 531, the current state i is cleared.
Is a state (i ≧ MP) after the state in which the mask point MP is set. Mask point
The MP does not immediately accept a key-off that has occurred earlier, and forms a key-off envelope after an envelope waveform is formed up to the mask point MP. Therefore, if the current state i is a state (i <MP) before the state MP in which the mask point MP is set, after performing the envelope level increasing / decreasing process of the subroutine (FIG. 6) in step 532, 55
Proceed to step 1. In this case, the same envelope forming processing as during key-on is continued.

If the determination result of step 531 is "YES", that is, if the current state i is a state after the state where the mask point MP is set (i ≧ MP), then in step 533, the current state i changes the decay point DP. It is determined whether or not the state after the set state (i> DP). The decay point DP is provided to make the envelope waveform after key-off different depending on whether the key-off is before or after that. If the current state i is a state before the state where the decay point DP is set (i ≦ DP), the DP inhibit flag DPINH is checked in step 534. DP inhibit mode (DPINH
= 1) means to ignore the decay point DP. Therefore, if the DP inhibit plug DPINH is 1, a standard key-off envelope waveform set according to each of the synth mode and the normal mode is formed in steps 541 and later described later. On the other hand, if the DP inhibit plug DPINH is 0, a key-off envelope waveform different from the standard key-off envelope waveform corresponding to the key-off before the decay point DP is formed. That is, in step 535, the synth flag SYNM
Is checked, and if it is a synth mode (SYNM = 1), a release / sustain process of a subroutine (FIG. 7) described later is executed in step 536, and then the process proceeds to step 551.

Referring to FIG. 7, in step 701, the sustain flag SUSON is checked. If sustain on (SUSON = 1), the envelope level EGj is set to the sustain rate SUSR
After attenuating only, on the other hand, sustain off (SUSON =
If it is 0), the envelope level EGj is attenuated by the release rate RR, and then the envelope level data EGj is transmitted to the tone generator 16 in step 704, and in step 705, whether the envelope level EGj is greater than 0 or not. Is determined. Envelope level EGj is 0 or less (EGj ≦
If 0), the level EGj is set to 0 in step 706, and the key-off flag KOFFj is set to 1 in step 707. On the other hand, the envelope level EGj is larger than 0 (EGj
If> 0), the process returns to the original routine (step 551 in FIG. 5B). In step 706, the level EGj is 0
And the key-off flag is set to KOFFj =
If set to 1, the timer interrupt processing of FIG.
From the subroutine and step 538 to be described later.
It is executed without going through. For this reason, the envelope level EGj remains constant at 0. That is, the envelope waveform formation of the channel ends.

Returning to FIG. 5B, if the result of the determination in step 535 is the normal mode (SYNM = 0), the state number i is set to DP in step 537 (state jump), and then the envelope level is determined in step 538. EGj is in state
It is determined whether or not the DP has reached the target level Li (i = DP). If the target level Li has not been reached (EGj ≦ Li),
After executing the release / sustain process in the subroutine of FIG. 7 in the step 536, the process proceeds to a step 551. If the target level Li has been reached (EG
j> i), in step 539, an envelope attenuation process is performed with the decay rate Ri (i = DP), which is the rate of the state DP, and in step 540, the envelope level data EGj is sent to the tone generator 16; Proceed with the process.

On the other hand, if the result of the determination in the step 533 is after the decay point DP (i> DP), the standard key-off envelope waveform forming processing of the step 541 and subsequent steps is executed. That is, in step 541, the synth mode flag SYNM is checked. In the normal mode (SYNM = 0), the release / sustain process of the subroutine (FIG. 7) is executed in step 542, and then the process proceeds to step 551. Therefore, when the key is turned off after the decay point DP in the normal mode (SYNM = 0) (i> DP),
The key-off envelope waveform is calculated in the subroutine (7th
It becomes a release or sustain waveform formed by the processing of FIG. That is, the standard key-off envelope waveform in the normal mode (SYNM = 0) is a release or sustain waveform.

On the other hand, the result of the determination in step 541 is the synth mode (S
If YNM = 1), it is determined in step 543 whether or not the current state number i is after the hold point HP. If it is before the hold point HP (i ≦ HP), after setting the state number i to HP + 1 which is the state number immediately after the hold point (state jump) in step 544, after the hold point HP (i> HP), If so, the process proceeds to step 545. Step 5
At step 45, after executing the envelope level increasing / decreasing process of the subroutine (FIG. 6), the process proceeds to step 551.

In steps 551 to 553, the sound channel is switched to the next channel. That is, after incrementing the channel number j in step 551, it is determined in step 552 whether or not the channel number j has reached 16.
In this electronic musical instrument, the sounding channel is number j =
There are 16 from 0 to 15. Therefore, the channel number j
If the channel number j is 16 if it is not 16, the channel number is changed to j = 15 in step 553.
After setting the next number j = 0, the timer interrupt is released and the process returns to the main routine.

By the above operation, an envelope waveform as shown in FIGS. 8 to 11 can be formed.

8 to 11 show envelope waveform diagrams when the decay point DP is set to 1 and the hold point HP is set to 3. In each of the figures, the attack rate R0 is set to a value smaller than the maximum value (95.25).

Such an envelope waveform is formed by detecting a key-on event (step 301 in FIG. 3), assigning a sound channel (step 302), and setting a key-on flag KONj (step 303). When a key-off event is detected (step 305),
The key-on flag KONj is reset (step 308)
As a result, an attenuation silencing process is performed.

First, in the timer interrupt processing (FIG. 5A) of the sounding channel immediately after the key-on detection, the initial values of the envelope level EGj and the state number i are set to 47.25 and 0 (attack state) in step 504, respectively. . Thus, the envelope waveform starts from an initial position specified by these initial values.

8 to 11 except for the release or sustain state RR / SUSR are formed by executing the processing of the step 602 or 603 (FIG. 6) each time a timer interrupt occurs. . Further, by the processing of the step 612, the gradient switching (state switching) in the envelope waveforms of FIGS. 8 to 11 is performed, and the steps 610 to 612 are performed.
Are skipped, a flat portion (hold state) shown in FIGS. 8 to 10 is formed. Further, the step 61
By setting the hold flag HOLDj at 1,
The state jump of step 523 is executed, and the eleventh state is executed.
The repetition of the state numbers 2 and 3 in the figure is realized.

Next, the formation of the envelope at the time of key-off will be described. In the following, the item numbers with circles correspond to the numbers with broken lines indicating the key-off envelope waveform in the figure.

In the case of the normal mode (SYNM = 0) and no mask point (MP = 0) shown in FIG. 8, the DP level (state) in the state 0 (attack state) which is the state prior to the state to which the decay point DP belongs. When the key is turned off in a state lower than L1), each time a timer interrupt occurs, step 53 in FIG. 5B is performed.
The program proceeds from step 8 to step 536 to execute the subroutine shown in FIG. 7, so that the rate is attenuated at the release or sustain rate. Then, when the envelope level EGj becomes 0 or less (step 705), the level EGj is set to 0 and the key-off flag KOFFj is set. As a result, in the subsequent timer interrupt, the processing is performed along the path from step 511 to step 525, so that the envelope level EGj remains 0 and is not increased or decreased. That is, the envelope waveform forming process ends.

When the key is turned off in a state higher than the DP level Li (i = DP) of the state (state 0) preceding the state to which the DP belongs (state 1), the envelope level EGj becomes D
Until the level falls to the P level, the damping process is performed at the rate of DP Ri (i = DP) at step 539 every time the timer interrupt occurs, and then the subroutine is executed at steps 538 and 536 to attenuate at the release or sustain rate. .

When the key is turned off in the state to which the DP belongs (state 1), the signal is attenuated at the DP rate up to the DP level and then attenuated at the release or sustain rate, as described above.

When the key is turned off in a state after the state to which the DP belongs (state 2 or later), the subroutine is executed in step 542, and the signal is attenuated at the release or sustain rate.

When the hold point HP is reached without being keyed off, the hold state is entered from there as described above. Then, when there is a key-off, similarly to the above, the subroutine is executed at step 542 every time a timer interrupt is performed, so that the signal is attenuated at the release or sustain rate.

In the case of the synth mode (SYNM = 1) and no mask point (MP = 0) shown in FIG.
FIG. Also, when the key is turned off in the state (state 1) to which the DP belongs, an attenuation waveform similar to the broken line in FIG. 8 is obtained.

If the key is turned off in the state after the state to which the DPs belonging to 'and' belong (state 2 and subsequent), the CPU jumps to the state HP + 1 (= 4) immediately after the hold point HP (= 3) (step 544). At each interrupt, the subroutine of FIG. 6 is executed at step 514. As a result, a key-off envelope waveform (key-off EG) based on the rate Ri and the target level Li set for each of the states 4 to 7 immediately after the hold point HP is formed. In other words, the target level at the rate R4 from the key-off level
Head to L4, then to level L5 at rate R5, rate R6
Goes to level L6 and attenuates to level L7 at rate R7. This envelope waveform can give a click feeling to the key-off sound. When the state number i becomes 8 (step 614), the key-off flag KOFFj is set (step 615). As a result, in the subsequent timer interrupt, the processing is performed on the route that goes from step 511 to step 525,
There is no increase or decrease in the envelope level EGj. That is, the envelope waveform forming process ends.

If the key reaches the hold point HP without being keyed off, it is held at that level, and if there is a key-off, it is attenuated by the key-off EG.

In the normal mode (SYNM = 0) and the mask point MP = 1 shown in FIG. 10, the state before the mask point MP (state 0,
For example, when key-off at point), the mask point MP
Until each timer interrupt occurs.
Since the process branches from 1 to step 532, the process of increasing / decreasing the envelope level EGj (subroutine in FIG. 6) is executed in step 532, but the operation does not shift to the key-off operation. Then, when the state number i is incremented in step 612 and reaches the mask point MP, similarly to FIG. 8, the state number i attenuates to the decay point DP at the rate R1 of the decay point DP (= 1), and then releases or releases. Decays at the sustain rate.

When DPINH = 1, it attenuates at the release or sustain rate regardless of where the key is turned off, regardless of the position of the decay point DP.

In the synth mode (SYNM = 1) shown in FIG. 11, when the mask point MP = 0, and when DPINH = 1, regardless of the position of the decay point DP, regardless of the position of the decay point DP, steps 533 or 5 are performed.
Since the process proceeds from step 34 to step 541, a key-off EG waveform is formed as in the case of FIGS.

When DPINH = 1, when the hold point HP (= 3) is reached (step 610), the decay point DP (=
It jumps to state DP + 1 (= 2) immediately after 1) (steps 611 and 523), and repeats the waveforms of states 2 and 3 (loop). When the key is turned off, a key-off EG waveform is formed as in the case of FIG.

[Application Examples of the Invention] The present invention is not limited to the above-described embodiments, and can be appropriately modified and implemented.

For example, in the above-described embodiment, control is performed by software, but control may be performed using dedicated hardware.

In the above description, an example in which the present invention is applied to an electronic keyboard instrument has been described. However, the present invention is also applicable to an internal sound source unit of a keyboard.

The mask point, decay point, and hold point can be set at arbitrary positions. Alternatively, it may be automatically set in accordance with the tone color.

The release and the sustain may be switched at the time of performance with a foot pedal or the like.

The envelope waveform is not limited to a waveform composed of a plurality of straight lines as in the above embodiment, and may be a waveform obtained by freely combining curves and the like. Further, the waveform is not limited to the one in which the envelope is formed by designating the level and the rate, and the waveform may be stored in the memory.

[Brief description of the drawings]

FIG. 1 is a hardware configuration diagram of an electronic musical instrument according to one embodiment of the present invention, FIGS. 2 to 7 are flowchart diagrams showing processing executed by a CPU in FIG. 1, and FIGS. FIG. 3 is an envelope waveform diagram formed by the tone generator circuit in FIG. 10: Central processing unit (CPU) 13: Key detection circuit 14: EG setting switch 16: Sound source circuit 18: Keyboard

Continuation of the front page (72) Inventor Tetsuji Ichiki 10-1 Nakazawa-cho, Hamamatsu-shi, Shizuoka Pref. Yamaha Corporation (56) References JP, A) Hikaru 1-101296 (JP, U)

Claims (2)

(57) [Claims] 1. A tone generator comprising: an envelope waveform signal forming means for forming an envelope waveform signal; and a tone signal generating means for generating a tone signal using the envelope waveform signal, wherein a specific position on the envelope waveform is determined. (A) instructing the tone signal generating means to perform key-off processing at the time of the key-off, and (b) timing of the key-off. If the position on the envelope waveform in the above is before the specific position, the key-off process in the envelope waveform signal forming means is performed until the envelope waveform signal formed by the envelope waveform signal forming means reaches the specific position. Without executing, the envelope formed by the envelope waveform signal forming means. When the envelope waveform signal reaches the specific position, a key-off process is performed in the envelope waveform signal forming means. (C) When a position on the envelope waveform at the key-off timing is later than the specific position And a control means for causing the envelope waveform signal forming means to execute a key-off process when the key-off occurs. 2. The method according to claim 1, wherein the specific position setting means arbitrarily sets first and second specific positions on an envelope waveform, and the control means sets the key-off timing before the first specific position. In this case, the key-off process in the envelope waveform signal forming means is delayed, and the envelope waveform signal is generated when the key-off timing is between the first specific position and the second specific position and when the key-off timing is after the second specific position. 2. A tone generator according to claim 1, wherein the attenuation means of the envelope waveform in the key-off process in said forming means is made different.