JP2020064189A - Electronic keyboard instrument, method and program - Google Patents

Abstract

To provide an electronic keyboard instrument that reproduces a way of sounding of an acoustic musical instrument in a musical performance.SOLUTION: An electronic keyboard instrument 200 acquires a first amplitude, refers to data indicative of characteristics of an attenuation curve stored in a ROM 230 to output musical sound data with a second amplitude determined according to the first amplitude, and generates a musical sound based upon the musical sound data. The characteristics of the attenuation curve includes: a first characteristic such that a first attenuation quantity from a first timing to a second timing is smaller than a second attenuation quantity from the second timing to a third timing; and a second characteristic such that a third attenuation quantity from a fourth timing to a fifth timing is smaller than a fourth attenuation quantity from the fifth timing to a sixth timing. When the first amplitude is larger than a certain level, a musical sound generated according to the first characteristic attenuates, and when the first amplitude is smaller than the certain level, a musical sound generated according to the second characteristic attenuates.SELECTED DRAWING: Figure 8

Description

  The present invention relates to an electronic keyboard instrument, method and program.

  Conventionally, various techniques have been developed for reproducing the state of musical sound attenuation in an acoustic piano in an electronic keyboard instrument. For example, in the electronic keyboard instrument described in Patent Document 1, if the key is released before the preset time elapses after the key is pressed, it is determined that the staccato playing method is performed, and the musical sound for the staccato playing method is determined. Reproduce the state of decay of.

JP-A-2009-198797

  However, the electronic keyboard instrument described in Patent Document 1 produces a musical sound when the key is released from the time the key is pressed until the preset time elapses, that is, when it is determined that the staccato playing style is performed. It simply delays the timing at which the decay of starts. For this reason, there is a problem in that the way the acoustic piano plays when played is not properly reproduced.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an electronic keyboard instrument, a method, and a program for reproducing how the acoustic piano plays when played.

  In order to achieve the above object, an electronic keyboard instrument according to an embodiment of the present invention has a keyboard having a plurality of keys, musical tone data, and a time lapse after key release of a tone generated based on the musical tone data. A memory for storing data indicating characteristics of an attenuation curve for muting including muffling, and at least one processor, wherein the at least one processor detects a key release Output in response to a weakening instruction receiving process for receiving a weakening instruction including muffling for a sound being produced based on the musical sound data, and the weakening instruction received by the weakening instruction receiving process. By referring to the amplitude acquisition processing for acquiring the first amplitude of the musical sound data and the data indicating the characteristic of the attenuation curve stored in the memory, the amplitude The second amplitude determined in accordance with the acquired first amplitude to output the musical sound data by resulting processing, executes a sound processing to sound a sound based on the musical sound data. The characteristic of the attenuation curve is that the first attenuation amount from the first timing to the second timing after the first timing is less than the second attenuation amount from the second timing to the third timing after the second timing. The first characteristic and the third attenuation amount from the fourth timing after the third timing to the fifth timing after the fourth timing are the fourth attenuation values from the fifth timing to the sixth timing after the fifth timing. And a second characteristic that is not less than the amount of attenuation, the musical tone generated according to the first characteristic is attenuated when the first amplitude is greater than a certain level, and the first amplitude is at a certain level. When it is smaller, the musical sound generated according to the second characteristic is attenuated.

  According to the present invention, it is possible to reproduce how the acoustic piano plays when played.

It is a figure for demonstrating the action at the time of a key depression in an acoustic piano. It is a figure for demonstrating the action at the time of key release in an acoustic piano. It is a figure which shows an example of the amplitude envelope after key release in an acoustic piano. It is a figure which shows an example of the characteristic of the amplitude envelope after key release in an acoustic piano. It is a figure which shows an example of the relationship between the amplitude of the string after key release in the case of a grand piano, and the maintenance factor of an amplitude. It is a figure which shows an example of the relationship of the amplitude of the string after key release in the case of an upright piano, and the maintenance factor of an amplitude. It is a block diagram which shows the hardware constitutions of the electronic keyboard instrument which concerns on one Embodiment of this invention. It is a figure which shows an example of the external appearance of an electronic keyboard instrument. 3 is a block diagram showing a schematic configuration of a sound source LSI. FIG. It is a flowchart which shows the procedure of a process of CPU. It is a figure which shows an example of the characteristic of the amplitude envelope after key release. It is a figure which shows an example of the amplitude envelope after key release in case the key release speed is fast. It is a figure which shows an example of the amplitude envelope after key release when the key release speed is slow. It is a figure which shows an example of the relationship between the velocity at the time of a key depression, and an initial amplitude. It is a figure which shows an example of the amplitude envelope after key depression.

  Hereinafter, the principle of the present invention will be described with reference to the accompanying drawings, and then an embodiment based on the principle of the present invention will be described. In the description of the drawings, the same elements will be denoted by the same reference symbols, without redundant description. Also, the dimensional ratios in the drawings are exaggerated for convenience of explanation, and may differ from the actual ratios.

[Principle of the Invention]
FIG. 1 is a diagram for explaining an action when a key is pressed in an acoustic piano. FIG. 2 is a diagram for explaining an action when releasing a key in an acoustic piano. FIG. 3A is a diagram showing an example of an amplitude envelope after key release in an acoustic piano. FIG. 3B is a diagram showing an example of a characteristic of an amplitude envelope after key release in an acoustic piano.

  In the acoustic piano 100, as shown in FIG. 1, when the key 110 is pressed, the damper 130 is disengaged from the string 120. Then, when the hammer 140 strikes the released string 120, the string 120 vibrates and a musical sound is produced. Further, as shown in FIG. 2, when the key 110 is released, the damper 130 comes into contact with the string 120, whereby the amplitude of the vibration of the string 120 is gradually attenuated, and the musical sound is muted.

  However, since the time that the damper 130 contacts the string 120 and the area where the damper 130 contacts the string 120 change depending on the magnitude of the amplitude of the string 120, the amplitude of the string 120 is always constant. It does not decay. For example, while the amplitude of the string 120 is large to some extent, the damper 130 is hit by the string 120 (bounced up) and cannot be in contact with the string 120 for a long time. During this time, the amplitude of the string 120 gradually and naturally attenuates as shown in FIGS. 3A and 3B.

  After that, when the amplitude of the string 120 becomes small to some extent, the damper 130 is not repelled by the string 120, and the contact time with the string 120 increases. The contact surface of the damper 130 is made of a soft material such as felt, and contacts the string 120 so as to wrap the string 120. Therefore, as the amplitude of the string 120 decreases, the area of the damper 130 in contact with the string 120 also increases. Thus, after the amplitude of the string 120 is reduced to some extent, both the time and the area of contact of the damper 130 with the string 120 increase, so that the amplitude of the string 120 is as shown in FIGS. 3A and 3B. Decays rapidly. That is, the amplitude of the string 120 is not linearly damped or damped along the exponential curve, but is damped along the dampening curve as shown in FIGS. 3A and 3B.

  More specifically, the amplitude of the string 120 has a first characteristic and a second characteristic as damping characteristics. As shown in FIG. 3B, the first characteristic is that the first attenuation amount A1 from the first timing T1 to the second timing T2 is smaller than the second attenuation amount A2 from the second timing T2 to the third timing T3. It is a characteristic. The second timing is a timing after the first timing, and the third timing is a timing after the second timing. In this embodiment, the elapsed time from the first timing to the second timing (T2-T1) and the elapsed time from the second timing to the third timing (T3-T2) are the same time. , (T2-T1) may be longer than (T3-T2). Further, the respective timings of the first timing T1, the second timing T2, and the third timing T3 are not limited to the timings illustrated in FIG. 3B, and any timing can be used as long as it satisfies the above-described first characteristic. May be

  On the other hand, the second characteristic is that the third attenuation amount A3 from the fourth timing T4 to the fifth timing T5 is not less than the fourth attenuation amount A4 from the fifth timing T5 to the sixth timing T6 (A3> A4, Alternatively, the characteristic is A3 = A4). The fourth timing is a timing after the third timing, the fifth timing is a timing after the fourth timing, and the sixth timing is a timing after the fifth timing. In this embodiment, the elapsed time from the fourth timing to the fifth timing (T5-T4) and the elapsed time from the fifth timing to the sixth timing (T6-T5) are the same time. , (T5-T4) may be shorter than (T6-T5). Further, the respective timings of the fourth timing T4, the fifth timing T5, and the sixth timing T6 are not limited to the timings illustrated in FIG. 3B, and any timing can be used as long as it satisfies the above-mentioned second characteristic. May be In the present embodiment, all of (T2-T1), (T3-T2), (T5-T4), and (T6-T5) are the same time.

  Therefore, as shown in FIG. 3B, when the amplitude level of the string 120 is higher than a certain level L1, the amplitude of the string 120 is attenuated according to the first characteristic. On the other hand, when the amplitude level of the string 120 is smaller than a certain level L1, the amplitude of the string 120 will be attenuated according to the second characteristic.

  Hereinafter, the attenuation characteristic of the amplitude of the string 120 in the acoustic piano 100 as described above will be further described from the viewpoint of the maintenance rate of the amplitude of the string 120.

  FIG. 4A is a diagram showing an example of the relationship between the amplitude of a string after key release and the amplitude maintenance rate in the case of a grand piano. FIG. 4B is a diagram showing an example of the relationship between the amplitude of the string after the key is released and the amplitude maintenance rate in the case of an upright piano.

  In FIGS. 4A and 4B, the “amplitude maintenance rate” means the maintenance rate of the amplitude with respect to the original amplitude after a certain time (for example, 1 ms) has elapsed. That is, the maintenance factor and the attenuation factor of the amplitude have a correlation that the attenuation factor increases (higher) as the maintenance factor decreases (lowers). For example, when the amplitude completely maintains the original amplitude after a lapse of a certain time, the amplitude maintenance ratio becomes 1.000, but the actual string vibration of the piano is generated even when the damper is not in contact. , Is gradually attenuated by various physical resistances, and thus becomes a value close to 1 such as 0.999. This means that after some time the amplitude changes to the original amplitude multiplied by 0.999.

  In FIGS. 4A and 4B, the “bass string” is a string in the low range (low range), for example, a string of any pitch in the range from the lowest pitch to the pitch one octave higher. Shall be shown. Further, the "medium tone string" is a string in the middle tone range (middle tone range), for example, a string having a pitch near the center (for example, C3). Further, the “treble string” is a string in the high range (high range), for example, any note in the range from the highest pitch to the pitch one octave below the pitch provided with the damper. It shall indicate the high string. However, the low-pitch string, the middle-pitch string, and the high-pitch string are not limited to these examples.

  As shown in FIGS. 4A and 4B, in both the grand piano and the upright piano, the larger the amplitude of the string, the larger the vibration energy and the less the amplitude is attenuated. Therefore, the amplitude maintenance rate increases. , The amplitude decays slowly. Further, as the pitch of the string is lower, the thickness of the string is thicker, the vibration energy is larger, and the amplitude is less likely to be attenuated. Also, especially in the low range, the length of the strings of the grand piano is longer than the length of the strings of the same pitch of the upright piano, and the strings of the grand piano vibrate more than the strings of the same pitch of the upright piano. Have energy. Therefore, especially in the bass range, the maintenance factor of the amplitude of the strings of the grand piano is larger than the maintenance factor of the amplitude of the strings of the upright piano, and the amplitude of the strings of the grand piano is greater than the amplitude of the strings of the upright piano. Also gradually declines.

  The present invention reproduces the attenuation characteristic of the amplitude of the string 120 in the acoustic piano 100 as described above in an electronic keyboard instrument.

Embodiment of the Invention
(Constitution)
FIG. 5 is a block diagram showing the hardware configuration of the electronic keyboard instrument according to the embodiment of the present invention. FIG. 6 is a diagram showing an example of the external appearance of an electronic keyboard instrument.

  As shown in FIGS. 5 and 6, the electronic keyboard instrument 200 includes a CPU (Central Processing Unit) 210, a RAM (Random Access Memory) 220, a ROM (Read Only Memory) 230, a switch panel 240, an LCD (liquid crystal display) 250. , A keyboard 260, a sound source LSI (large-scale integrated circuit) 270, a D / A converter 280, and an amplifier 290. Each of the CPU 210, the RAM 220, the ROM 230, and the tone generator LSI 270 is connected to the bus 295. Further, each of the switch panel 240, LCD 250 and keyboard 260 is connected to the bus 295 via each of the I / O interface 245, LCD controller 255 and key scanner 265.

  The CPU 210 as a processor executes control of each of the above-described components and various arithmetic processes according to a program. The RAM 220 temporarily stores programs, data, etc. as a work area.

  The ROM 230 as a memory has a program area and a data area, and stores various programs and various data in advance. The ROM 230 functions as a waveform memory, for example, and stores musical tone data (tone waveform data) of each musical instrument including an acoustic piano such as a grand piano or an upright piano.

  Further, in the present embodiment, the ROM 230 reproduces the attenuation characteristic of the amplitude of the string in the acoustic piano as described above, for each tone color and range, as shown in FIGS. 4A and 4B. Data indicating the relationship between the amplitude of the string and the maintenance factor of the amplitude is stored in advance. More specifically, the ROM 230 shows the characteristics of the attenuation curve for reducing the sound generated based on the musical sound data, including the muting according to the lapse of time after the key is released (the characteristics of the attenuation curve. The data as shown in FIG. 4A and FIG. That is, it can be said that the characteristic of the attenuation curve is a characteristic characterized by the relationship between the amplitude of the string after key release and the amplitude maintenance rate as shown in FIGS. 4A and 4B.

  The ROM 230 includes, for example, each tone color corresponding to the type of acoustic piano such as a grand piano or upright piano, and each tone range included in the range from the lowest pitch to the highest pitch provided with a damper. Then, the data is stored. The ROM 230 stores data corresponding to a part of the pitch in the range from the lowest pitch to the highest pitch provided with the damper as representative data of a certain range including the pitch, Data corresponding to all pitches may be stored. Further, the ROM 230 may store data obtained experimentally in the acoustic piano as data indicating the relationship between the amplitude of the string after key release and the maintenance rate of the amplitude, or by various simulations such as numerical calculation. The predicted and acquired data may be stored. Further, the ROM 230 may store data in the form of a graph as shown in FIG. 4A or FIG. 4B, or may store data in other forms such as a table.

  In the present embodiment, the ROM 230 uses the data indicating the relationship between the amplitude of the string after the key is released and the amplitude maintenance rate as the velocity (key release speed) at the time of key release detected by the electronic keyboard instrument 200. It should be stored in association with each other. In the following, a case will be described as an example in which the ROM 230 stores data indicating the relationship between the amplitude of the string after the key is released and the maintenance factor of the amplitude as data when the velocity value at the time of key release is 64. . That is, the ROM 230 has data obtained experimentally on the assumption that the velocity value at the time of key release is 64 as data indicating the relationship between the amplitude of the string after key release and the maintenance rate of the amplitude, and various data. The data predicted and obtained by the simulation may be stored. However, the velocity value associated with the data indicating the relationship between the amplitude of the string after the key is released and the maintenance factor of the amplitude is not limited to the value described above.

  The switch panel 240 includes a plurality of switches 241 as operators, and receives a player's operation of pressing each of the plurality of switches 241. The switch panel 240 includes, for example, a plurality of switches 241 as operators for selecting one of a plurality of musical instrument sounds. The I / O interface 245 monitors the plurality of switches 241 in the switch panel 240, and when detecting the pressing of each of the plurality of switches 241, notifies the CPU 210.

  The LCD 250 displays various information. The LCD controller 255 is an IC (integrated circuit) that controls the LCD 250.

  The keyboard 260 is provided with a plurality of keys 261 and receives a key depression operation and a key release operation performed by the performer. Each of the plurality of keys 261 may operate, for example, with one end of a leaf spring or the like as a fulcrum, and may be provided with a plurality of switches (contacts) below which are sequentially turned on or off by key depression or key release.

  The key scanner 265 monitors a plurality of keys 261 on the keyboard 260 and detects a key press or a key release of each of the plurality of keys 261. For example, when the key scanner 265 detects a key depression, it detects the key number (note number) of the depressed key 261 and the velocity (key pressing speed) at the time of key depression, and notifies the CPU 210. When the key scanner 265 detects the key release, it detects the key number of the released key 261 and the velocity (key release speed) at the time of key release, and notifies the CPU 210 of the detected key number. The key scanner 265 detects the velocity at the time of key depression or key release, for example, by measuring the time difference when at least two switches included in each of the plurality of keys 261 are detected to be turned on or off. When the CPU 210 receives a tone generation instruction (note-on instruction) by detecting a key depression by the key scanner 265, the CPU 210 executes a process for generating a tone according to the received tone generation instruction. Further, when the CPU 210 receives a weakening instruction (eg, a note-off instruction) that includes muffling of a musical sound that is being generated due to the key release detected by the key scanner 265, the musical tone is softened according to the received weakening instruction. Processing to make the sound mute.

  The tone generator LSI 270 as a processor adopts a well-known waveform memory reading method and reads the waveform data of the selected musical instrument sound from the ROM 230 functioning as a waveform memory. The tone generator LSI 270 has a plurality of channels, and is configured to be able to read different waveform data from each of the plurality of channels. The tone generator LSI 270 processes the read waveform data and outputs it to the D / A converter 280. Details of the tone generator LSI 270 will be described later.

  The D / A converter 280 converts the digital waveform data output from the sound source LSI 270 into an analog waveform signal and outputs the analog waveform signal to the amplifier 290. The amplifier 290 amplifies the analog waveform signal output from the D / A converter 280 and outputs it to a speaker or an output terminal (neither is shown).

  The electronic keyboard instrument 200 may include components other than the components described above, or may not include some of the components described above.

  Next, the sound source LSI 270 will be described in detail. FIG. 7 is a block diagram showing a schematic configuration of the sound source LSI.

  As shown in FIG. 7, the tone generator LSI 270 functions as a waveform generator 271, a pitch envelope generator 272, a filter 273, a filter envelope generator 274, an amplifier 275, an amplifier envelope generator 276, and an amplitude value detector 277. The sound source LSI 270 causes each component to function in each of the plurality of channels. The sound source LSI 270 also functions as a mixer 278 that adjusts and mixes the outputs from the amplifier 275 in each of the plurality of channels.

  The waveform generator 271 generates a waveform in which the pitch is controlled according to the pitch envelope set by the pitch envelope generator 272 and indicating the time change of the pitch. More specifically, the waveform generator 271 controls the pitch by reading the waveform data from the ROM 230 at the read speed corresponding to the pitch envelope. The waveform generator 271 may generate the waveform of the continuous sound by executing a loop process of repeatedly reading the waveform data from the ROM 230. The filter 273 controls the sound quality of the sound based on the waveform according to the filter envelope set by the filter envelope generator 274 and indicating the time change of the cutoff frequency of the filter (for example, a low-pass filter). The amplifier 275 controls the level of the sound based on the waveform, that is, the amplitude of the waveform, according to the amplifier envelope which is set by the amplifier envelope generator 276 and indicates the temporal change of the level (volume).

  Each envelope generator 272, 274, 276 sets each envelope based on the parameters supplied from the CPU 210. For example, the amplifier envelope generator 276 sets the amplifier envelope based on the target amplitude value supplied from the CPU 210 and the parameter regarding the rate for reaching the target amplitude value. When the amplitude value of the waveform reaches 0 (zero) according to the amplifier envelope, the amplifier envelope generator 276 is stopped, and the reading of the waveform data by the waveform generator 271 is also stopped.

  The amplitude value detection unit 277 is composed of a rectifier circuit, a low-pass filter, etc., and detects an amplitude value indicating the amplitude of the musical sound data output from the amplifier 275. The CPU 210 acquires the amplitude value of the musical sound data detected by the amplitude value detection unit 277 from the amplitude value detection unit 277. In the present embodiment, the “amplitude value” may mean any one of the effective value of the amplitude, the peak value and the average value, or the amplitude level calculated based on the effective value of the amplitude. Good.

(motion)
Next, the operation of the process executed by the CPU 210 will be described in detail with reference to FIG.

  FIG. 8 is a flowchart showing the procedure of processing by the CPU. The algorithm shown in the flowchart of FIG. 8 is stored in the ROM 230 or the like as a program and executed by the CPU 210. It is assumed that the CPU 210 is executing a process of producing a musical sound by detecting a key depression of one of the plurality of keys 261 before the process shown in FIG.

  As shown in FIG. 8, the CPU 210 receives (accepts) a weakening instruction including muting for a musical sound generated based on the musical sound data by detecting the release of one of the keys 261. It is determined whether or not a certain sound reduction instruction receiving process has been executed (step S101).

  When it is determined that the weakening instruction for the musical sound has not been received, that is, the weakening instruction receiving process has not been executed (step S101: NO), the CPU 210 ends the process shown in FIG.

  When it is determined that the softening instruction for the musical sound has been received, that is, the softening instruction receiving process has been executed (step S101: YES), the CPU 210 proceeds to the process of step S102. Then, the CPU 210 controls the sound source LSI 270 so as to set the amplifier envelope to the release state according to the weakening instruction received by the weakening instruction receiving process in step S101 (step S102). In the release state, the target amplitude value and rate set in the amplifier envelope can be updated every certain time (for example, 1 ms).

  Subsequently, the CPU 210 indicates the relationship between the amplitude of the released string and the amplitude maintenance rate stored in the ROM 230, based on the tone color being sounded and the key number of the released key 261. The data is acquired for reference (step S103). The CPU 210 indicates, for example, the amplitude and amplitude of the string after key release corresponding to the tone color corresponding to the type of acoustic piano such as a grand piano or upright piano and the range including the pitch of the released key number. Acquire data showing the relationship with the maintenance rate. As described above, in the data stored in the ROM 230, the maintenance factor of the amplitude of the string of the grand piano is set to be larger than the maintenance factor of the amplitude of the string of the upright piano, particularly in the low tone range. . Further, the maintenance rate of the amplitude of the bass string is set to be larger than the maintenance rate of the amplitude of the treble string.

  When the ROM 230 stores the data corresponding to all the pitches in the range from the lowest pitch to the highest pitch provided with the damper, the CPU 210 corresponds to the pitch of the key number. You may acquire the data. Further, when the ROM 230 stores the data corresponding to a part of the pitch, the CPU 210 determines the pitch of the key number based on the data corresponding to the part of the pitch stored in the ROM 230. May be predicted and acquired. For example, the CPU 210 may interpolate and acquire data corresponding to a pitch string between the low-pitched string and the high-pitched string based on the above-described data regarding the low-pitched string and the high-pitched string.

  Subsequently, the CPU 210 is an amplitude value acquisition process (amplitude acquisition process) that is a process of acquiring an amplitude value indicating the current amplitude (first amplitude) of the output musical sound data detected by the amplitude value detection unit 277. Is executed (step S104). When executing step S104 for the first time, the CPU 210 acquires the amplitude value of the tone data at the time of key release detected by the amplitude value detection unit 277. Then, the CPU 210 responds to the data indicating the relationship between the amplitude of the string after key release and the amplitude maintenance rate acquired in step S103, and the amplitude value of the musical sound data acquired by the amplitude value acquisition process in step S104. Then, the maintenance rate of the amplitude of the musical sound data is acquired (step S105).

  Here, the maintenance rate of the amplitude of the musical sound data corresponds to the maintenance rate of the amplitude of the strings stored in the ROM 230, and the maintenance rate of the amplitude after the elapse of a certain time (for example, 1 ms) with respect to the original amplitude. Shall be Further, the amplitude of the output musical sound data corresponds to the amplitude of the strings. The CPU 210, for example, associates the maximum and minimum amplitude values of a string with the maximum and minimum amplitude values of a musical tone, and interpolates the amplitude values between them to obtain the amplitude of the string after key release and the maintenance rate of the amplitude. The amplitude of the strings in the data indicating the relationship may be normalized (converted) to the amplitude of the musical sound data. Then, the CPU 210 determines the amplitude of the tone data in accordance with the data indicating the relationship between the normalized amplitude of the tone data after key release and the amplitude maintenance rate, and the amplitude value of the tone data acquired in step S104. The maintenance rate of may be acquired.

  Subsequently, the CPU 210 confirms the velocity value of the released key 261 when the key is released, and based on the velocity value, corrects (changes) the amplitude maintenance rate acquired in step S105 and determines it ( Step S106). The velocity at the time of releasing the key is detected, for example, as described above, by measuring the time difference when at least two switches included in the released key 261 are detected to be off.

  The CPU 210 corrects the amplitude maintenance rate based on the confirmed velocity value and the following equation, for example.

  Here, d'is a corrected amplitude maintenance rate, d is an amplitude maintenance rate acquired in step S105, and v is a velocity value (value of 0 to 127). This equation means that the value of d'is changed according to the obtained velocity value v at the time of releasing the key. Here, when the obtained velocity value at the time of key release is 64, d ′ = d, and the amplitude maintenance rate is not corrected. The CPU 210 corrects the amplitude maintenance rate acquired in step S105 according to the velocity value at the time of key release that is actually detected. As a result, the larger the acquired velocity value at key release, that is, the faster the key release speed, the smaller the amplitude maintenance rate (the larger the amplitude attenuation rate) is adjusted. That is, the after-release after key release is adjusted to be short. On the contrary, the smaller the obtained velocity value at the time of releasing the key, the longer the lingering sound after releasing the key is adjusted.

  Subsequently, the CPU 210 multiplies the amplitude value of the musical sound data acquired in step S104 by the amplitude maintenance rate corrected in step S106 to calculate the target amplitude value after a lapse of a certain time (for example, 1 ms). Yes (step S107). That is, it can be said that the CPU 210 calculates the target amplitude value based on the current amplitude value of the musical sound data and the velocity value at the time of key release (the amplitude maintenance rate corrected based on the velocity value). Further, the CPU 210 calculates the rate to be set in the amplifier envelope in order to reach the target amplitude value after a certain time has elapsed from the current amplitude value of the musical sound data (step S108).

  Subsequently, the CPU 210 sets the target amplitude value calculated in step S107 and the rate calculated in step S108 in the amplifier envelope generator 276 of the sound source LSI 270 (step S109). Then, the CPU 210 is a process of determining an amplitude value indicating the amplitude (second amplitude) at which the musical sound data is output, based on the target amplitude value and the rate calculated according to the current amplitude value of the musical sound data. The process is executed (step S110). Further, the CPU 210 executes a sound generation process, which is a process of generating a musical tone based on the musical tone data by outputting the musical tone data with the amplitude value determined by the determination process in step S110 (step S111). The CPU 210 repeats the processing of steps S110 and S111 until the amplitude value reaches the target amplitude value. After that, the CPU 210 ends the process.

  After that, the CPU 210 repeats the processing of steps S104 to S111 of FIG. 8 each time the amplitude value reaches the target amplitude value until the amplitude value of the musical sound data detected by the amplitude value detection unit 277 reaches 0. . Since the time until the amplitude value of the musical sound data reaches a next target amplitude value from a certain target amplitude value is constant, the CPU 210, at a certain time, until the amplitude value of the musical sound data reaches 0. The processing of steps S104 to S111 in FIG. 8 will be repeated. That is, the CPU 210 obtains the amplitude maintenance rate according to the amplitude value of the musical tone data every certain time, and updates the target amplitude value and the rate set in the tone generator LSI 270 according to the amplitude maintenance rate to update the musical tone data. The process of attenuating the amplitude is repeated. In other words, the CPU 210 updates the target amplitude value and the rate set in the tone generator LSI 270 according to the amplitude attenuation rate that has a correlation with the amplitude maintenance rate every certain time to attenuate the amplitude of the musical sound data. Can be said to repeat.

(Action effect)
Subsequently, the effects of the present embodiment will be further described with reference to FIGS. 9A to 9C. The electronic keyboard instrument 200 realizes the attenuation characteristic of the amplitude of the musical sound data as shown in FIGS. 9A to 9C by executing the processing shown in FIG.

  FIG. 9A is a diagram showing an example of the characteristic of the amplitude envelope after key release. FIG. 9B is a diagram showing an example of the amplitude envelope after key release when the key release speed is fast. FIG. 9C is a diagram showing an example of the amplitude envelope after key release when the key release speed is slow. In FIGS. 9A to 9C, the amplitude value (amplitude level) “1.0” indicates the maximum amplitude value that can be output.

  The electronic keyboard instrument 200 determines the amplitude value to be output immediately after, by determining the amplitude maintenance rate according to the amplitude value of the musical sound data. Thereby, as shown in FIG. 9A, the electronic keyboard instrument 200 can gently reduce the amplitude while the amplitude value of the tone data after key release is larger than a certain amplitude value L1. That is, when the amplitude value is larger than a certain amplitude value L1 (for example, 0.8), the electronic keyboard musical instrument 200 has an amplitude immediately after being determined by the determination process than when the amplitude value is the certain amplitude value L1. The value can be set to a large value (that is, the amplitude maintenance rate is large or the attenuation rate is small) to gently attenuate the amplitude. On the other hand, the electronic keyboard instrument 200 can quickly attenuate the amplitude after the amplitude value becomes smaller than the certain amplitude value L1. When the amplitude value is smaller than a certain amplitude value L1 (for example, 0.8) from the beginning, the electronic keyboard instrument 200 can quickly attenuate the amplitude according to, for example, an exponential curve.

  More specifically, the amplitude of the musical sound data has the first characteristic and the second characteristic as the attenuation characteristic, like the amplitude of the string 120 as described above. As shown in FIG. 9A, the first characteristic is that the first attenuation amount A1 from the first timing T1 to the second timing T2 is smaller than the second attenuation amount A2 from the second timing T2 to the third timing T3. It is a characteristic. The second timing is a timing after the first timing, and the third timing is a timing after the second timing. In the example shown in FIG. 9A, the elapsed time from the first timing to the second timing (T2-T1) and the elapsed time from the second timing to the third timing (T3-T2) are the same time, but ( T2-T1) may be longer than (T3-T2). Further, the respective timings of the first timing T1, the second timing T2, and the third timing T3 are not limited to the timings illustrated in FIG. 9A, and any timing can be used as long as it satisfies the above-described first characteristic. May be

  On the other hand, the second characteristic is that the third attenuation amount A3 from the fourth timing T4 to the fifth timing T5 is not less than the fourth attenuation amount A4 from the fifth timing T5 to the sixth timing T6 (A3> A4, Alternatively, the characteristic is A3 = A4). The fourth timing is a timing after the third timing, the fifth timing is a timing after the fourth timing, and the sixth timing is a timing after the fifth timing. In the example shown in FIG. 9A, the elapsed time from the fourth timing to the fifth timing (T5-T4) and the elapsed time from the fifth timing to the sixth timing (T6-T5) are the same time. T5-T4) may be shorter than (T6-T5). Further, the respective timings of the fourth timing T4, the fifth timing T5, and the sixth timing T6 are not limited to the timings illustrated in FIG. 9A, and any timing may be used as long as it satisfies the above-mentioned second characteristic. May be

  Therefore, as shown in FIG. 9A, when the amplitude value of the musical tone data is larger than a certain amplitude value L1, the amplitude of the musical tone data to be output, and thus the musical tone to be sounded, is attenuated according to the first characteristic. become. On the other hand, when the amplitude value of the musical tone data is smaller than a certain amplitude value L1, the amplitude of the musical tone data that is output, and thus the musical tone that is sounded, is attenuated according to the second characteristic. As a result, the electronic keyboard instrument 200 can reproduce the attenuation characteristic of the amplitude of the string in the acoustic piano as described above.

  In addition, the electronic keyboard instrument 200 can quickly attenuate the amplitude when the key release speed is higher than a certain speed (hereinafter referred to as “first speed”) by correcting the amplitude maintenance rate. . That is, when the key release speed is faster than the first speed, the electronic keyboard instrument 200 reduces the amplitude value immediately after the determination process is performed (that is, the amplitude of the amplitude is smaller than that when the key release speed is the first speed). The maintenance factor can be set to be small overall or the attenuation factor can be set to be large overall) to quickly attenuate the amplitude. It should be noted that the case where the key release speed is higher than the first speed corresponds to the case where the velocity value at the time of key release is larger than the first velocity value (for example, 64) corresponding to the first speed. As a result, the electronic keyboard instrument 200 can reflect the influence of the key release speed on the amplitude attenuation characteristic.

  As described above, the electronic keyboard instrument 200 according to the present embodiment performs the weakening instruction receiving process for receiving the weakening instruction including the muting of the musical sound and the amplitude value indicating the current amplitude (first amplitude) of the musical sound data. By referring to the amplitude acquisition processing to be acquired and the data indicating the characteristics of the attenuation curve stored in the ROM 230, the musical tone data is output with the amplitude value indicating the amplitude (second amplitude) determined according to the current amplitude value. Then, a tone generation process for generating a tone based on the tone data is executed. The characteristics of the attenuation curve are as follows: the first characteristic in which the first attenuation amount from the first timing to the second timing is smaller than the second attenuation amount from the second timing to the third timing, and the first characteristic from the fourth timing to the fifth timing. And a second characteristic in which the third attenuation amount is not less than the fourth attenuation amount from the fifth timing to the sixth timing. When the current amplitude value is higher than a certain level, the musical tone generated according to the first characteristic is attenuated, and when the current amplitude value is smaller than the certain level, the musical tone generated according to the second characteristic is attenuated. Decays. As a result, the electronic keyboard instrument 200 can appropriately reproduce how the acoustic piano is played when the acoustic piano is played, without delaying the timing of starting the attenuation of the musical sound or being influenced by whether or not the staccato playing method is performed. That is, the electronic keyboard instrument 200 can reproduce the damping characteristic of the amplitude of the string in the acoustic piano, that is, when the amplitude of the string is large, the damper is repelled by the string and the amplitude of the string gradually and naturally attenuates.

  Further, in the electronic keyboard instrument 200, the amplitude value to be output is determined based on the current amplitude value and the key release speed. As a result, the electronic keyboard instrument 200 can reflect the influence of the key release speed on the amplitude attenuation characteristic. In other words, the electronic keyboard instrument 200 can reflect the influence of the key release speed that the amplitude is rapidly attenuated when the key release speed is high, on the amplitude attenuation characteristic.

  In addition, in the electronic keyboard instrument 200, the characteristics of the attenuation curve in the lower range than a certain sound and the characteristics of the attenuation curve in the higher range than a certain sound are set to be different. As a result, the electronic keyboard instrument 200 can reflect the influence of the thickness of the string, that is, the amplitude gradually attenuates when the thickness of the string is thick, on the amplitude attenuation characteristic.

  Further, in the electronic keyboard instrument 200, the characteristics of the attenuation curve are set to be different for each timbre. As a result, the electronic keyboard instrument 200 can accurately reproduce the attenuation characteristic of different amplitude for each tone color corresponding to the type of acoustic piano such as a grand piano or an upright piano.

  The present invention is not limited to the above-described embodiment, and various modifications and improvements can be made within the scope of the claims.

  For example, in the above-described embodiment, the case where the amplitude maintenance rate is acquired based on the data indicating the relationship between the amplitude of the string after key release and the amplitude maintenance rate has been described as an example. However, the electronic keyboard instrument 200 may store in advance data indicating the relationship between the amplitude of the string after the key is released and the attenuation rate of the amplitude, and may acquire the attenuation rate of the amplitude based on the data. Then, the electronic keyboard instrument 200 may calculate the target amplitude value and rate based on the attenuation rate of the amplitude instead of the maintenance rate of the amplitude.

  In the above-described embodiment, the case where the amplitude maintenance rate is acquired according to the amplitude value of the musical sound data has been described as an example in step S105, but the amplitude maintenance rate is acquired by another method. Good. For example, the electronic keyboard instrument 200 may store in advance a plurality of tables, graphs, and the like indicating the temporal change of the amplitude maintenance rate. Then, the electronic keyboard instrument 200 selects an appropriate one from a plurality of tables and graphs according to the amplitude value of the musical sound data at the time of releasing the key, and thereafter, the amplitude maintenance rate of the amplitude indicated by the selected table or graph, etc. The maintenance factor of the amplitude may be acquired according to the time change.

  Further, in the above-described embodiment, the case where the amplitude maintenance rate is corrected based on the formula in step S106 has been described as an example, but the amplitude maintenance rate may be corrected by another method. For example, the electronic keyboard instrument 200 may store in advance a table, a graph, or the like showing the relationship between the velocity at the time of releasing the key and the correction amount of the amplitude maintenance rate, and instead of the formula, based on the table, the graph, or the like, The maintenance factor of the amplitude may be corrected.

  Further, in the above-described embodiment, the case where the CPU 210 executes the process illustrated in FIG. 8 has been described as an example, but at least a part of the process illustrated in FIG. 8 may be executed by the tone generator LSI 270.

  Further, in the above-described embodiment, the case where the amplitude value of the musical sound data is detected by the amplitude value detection unit 277 in step S104 has been described as an example, but the amplitude value may be acquired by another method. . Hereinafter, with reference to FIGS. 10 and 11, another method for acquiring the amplitude value of the musical sound data will be described as a modified example.

(Modification)
FIG. 10 is a diagram showing an example of the relationship between the velocity and the initial amplitude when a key is pressed. FIG. 11 is a diagram showing an example of the amplitude envelope after key depression.

  In the modification, the CPU 210 predicts and acquires the amplitude value of the musical sound data at the time of releasing the key based on the data as shown in FIGS. 10 and 11. More specifically, as the amplitude value acquisition processing in step S104, the CPU 210 does not acquire the amplitude value of the musical sound data detected by the amplitude value detection unit 277, but based on the data shown in FIGS. 10 and 11. Then, a process of predicting and acquiring the amplitude value of the musical sound data is executed. Therefore, in the modified example, the ROM 230 stores, for each tone color and tone range, data indicating the relationship between the velocity at the time of key depression and the initial amplitude as shown in FIG. 10 and the amplitude after key depression as shown in FIG. The envelope setting data is stored in advance. Further, since the CPU 210 does not acquire the amplitude value of the musical sound data detected by the amplitude value detection unit 277, the tone generator LSI 270 may not have the function as the amplitude value detection unit 277.

  The CPU 210 executes the following processing of acquiring the predicted value of the initial amplitude of the musical sound and processing of confirming the time change of the amplitude during the key depression, so that the amplitude value of the musical sound data at the time of key release is executed. Predict and get.

  First, the CPU 210 obtains the predicted value of the initial amplitude of the musical tone based on the velocity at key depression and the data stored in the ROM 230 showing the relationship between the velocity at key depression and the initial amplitude. In one example, as shown in FIG. 10, when the velocity value at the time of key depression is 64, 0.8 is acquired as the predicted value of the initial amplitude of the musical sound. However, the content of the data indicating the relationship between the velocity at the time of key depression and the initial amplitude is not limited to the example shown in FIG. The velocity at the time of key depression is detected by, for example, as described above, by measuring the time difference at which at least two switches of the depressed key 261 are detected to be turned on.

  Then, the CPU 210 predicts the amplitude of the musical tone data at the time of key release based on the elapsed time from the key being pressed until the key is released, and the setting data of the amplitude envelope after key pressing stored in the ROM 230. Get the value. That is, the CPU 210 confirms the time change during the key depression of the above-mentioned initial amplitude of the musical sound based on the elapsed time and the data. In one example, as shown in FIG. 11, when the elapsed time is t time, the predicted value of the initial amplitude of the musical sound is further multiplied by 0.5 as the predicted value of the amplitude of the musical sound data at key release. To be acquired. However, the setting of the amplitude envelope after key depression is not limited to the example shown in FIG.

  After that, the CPU 210 executes the processing of steps S105 to 109 by using the above-described predicted value of the amplitude of the musical sound data at the time of key release as the amplitude value of the musical sound data acquired by the amplitude value acquisition processing. However, the CPU 210 needs to temporarily store the target amplitude value in the RAM 220 or the like each time the target amplitude value is calculated in step S107.

  After that, the CPU 210 repeats the processing of steps S105 to S111 of FIG. 8 every time the predicted value of the amplitude of the musical sound data reaches the target amplitude value. The CPU 210 acquires the reached target amplitude value from the RAM 220 or the like as the predicted value of the amplitude of the new musical sound data each time the predicted value of the amplitude of the musical sound data reaches the target amplitude value, that is, every certain time. Then, the CPU 210 acquires the amplitude maintenance rate of the musical sound data according to the predicted value of the amplitude of the new musical tone data, updates the target amplitude value and rate set in the tone generator LSI 270 in accordance with the amplitude maintenance rate, and updates the musical tone data. The process of attenuating the amplitude of is repeated. As a result, the CPU 210 can execute the processing according to the present embodiment even when the tone generator LSI 270 cannot function as the amplitude value detection unit 277 and cannot acquire the actual measurement value of the amplitude of the musical sound data, and when the acoustic piano is playing, for example. You can properly reproduce how you ring.

  In addition, the present invention is not limited to the above-described embodiment, and can be variously modified at the stage of implementation without departing from the spirit of the invention. Further, the functions executed in the above-described embodiments may be combined appropriately as much as possible. The above-described embodiment includes various stages, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent elements. For example, even if some constituent elements are deleted from all the constituent elements shown in the embodiment, if the effect can be obtained, the structure in which the constituent elements are deleted can be extracted as the invention. In the following, the inventions described in the claims at the beginning of the application will be additionally described.

(Appendix)
[Claim 1]
A keyboard with multiple keys,
A memory storing the tone data, and data indicating the characteristics of an attenuation curve for weakening the sound being produced based on the tone data, including muting according to the time elapsed after the key is released. ,
At least one processor,
Equipped with
The at least one processor is
A weakening instruction receiving process for receiving a weakening instruction including muffling for a sound being produced based on the tone data by detecting the key release;
An amplitude acquisition process for acquiring a first amplitude of the musical sound data to be output in response to the weakening instruction received by the weakening instruction receiving process,
Outputting the tone data with a second amplitude determined according to the first amplitude acquired by the amplitude acquisition processing by referring to data indicating the characteristics of the attenuation curve stored in the memory A sounding process for generating a sound based on the musical sound data,
Run
The characteristic of the attenuation curve is that the first attenuation amount from the first timing to the second timing after the first timing is less than the second attenuation amount from the second timing to the third timing after the second timing. The first characteristic and the third attenuation amount from the fourth timing after the third timing to the fifth timing after the fourth timing are the fourth attenuation values from the fifth timing to the sixth timing after the fifth timing. And a second characteristic that is not less than the amount of attenuation, the musical tone generated according to the first characteristic is attenuated when the first amplitude is greater than a certain level, and the first amplitude is at a certain level. If smaller, the musical sound generated according to the second characteristic is attenuated,
Electronic keyboard instrument.

[Claim 2]
A determination process of determining the second amplitude based on the first amplitude and a key release speed detected in response to key release;
The electronic keyboard instrument according to claim 1, wherein the sounding process outputs a sound based on the musical tone data by outputting the musical tone data at the second amplitude determined by the determining process.

[Claim 3]
The electronic keyboard instrument according to claim 2, wherein the second amplitude determined by the determination process is smaller when the key release speed is higher than the first speed than when the key release speed is the first speed.

[Claim 4]
The characteristic of the attenuation curve is different between a characteristic of an attenuation curve in a lower range than a certain sound and a characteristic of an attenuation curve in a higher range than the certain sound. Electronic keyboard instrument described.

[Claim 5]
The electronic keyboard musical instrument according to any one of claims 1 to 4, wherein the characteristic of the attenuation curve is different for each set tone color.

[Claim 6]
A keyboard with multiple keys,
A memory storing the tone data, and data indicating the characteristics of an attenuation curve for weakening the sound being produced based on the tone data, including muting according to the time elapsed after the key is released. ,
To the computer of the electronic keyboard instrument that has
A weakening instruction receiving process for receiving a weakening instruction including muffling for a sound being produced based on the tone data by detecting the key release;
An amplitude acquisition process for acquiring a first amplitude of the musical sound data to be output in response to the weakening instruction received by the weakening instruction receiving process,
Outputting the musical sound data with a second amplitude determined according to the first amplitude acquired by the amplitude acquisition processing by referring to data indicating the characteristics of the attenuation curve stored in the memory. A sounding process for generating a sound based on the musical sound data,
Run
The characteristic of the attenuation curve is that the first attenuation amount from the first timing to the second timing after the first timing is less than the second attenuation amount from the second timing to the third timing after the second timing. The first characteristic and the third attenuation amount from the fourth timing after the third timing to the fifth timing after the fourth timing are the fourth attenuation values from the fifth timing to the sixth timing after the fifth timing. And a second characteristic that is not less than the amount of attenuation, the musical tone generated according to the first characteristic is attenuated when the first amplitude is greater than a certain level, and the first amplitude is at a certain level. A method of causing a musical sound to be generated according to the second characteristic to be attenuated when the musical value is smaller than the predetermined value.

[Claim 7]
A keyboard with multiple keys,
A memory storing the tone data, and data indicating the characteristics of an attenuation curve for weakening the sound being produced based on the tone data, including muting according to the time elapsed after the key is released. ,
To the computer of the electronic keyboard instrument that has
A weakening instruction receiving process for receiving a weakening instruction including muffling for a sound being produced based on the tone data by detecting the key release;
An amplitude acquisition process for acquiring a first amplitude of the musical sound data to be output in response to the weakening instruction received by the weakening instruction receiving process,
Outputting the tone data with a second amplitude determined according to the first amplitude acquired by the amplitude acquisition processing by referring to data indicating the characteristics of the attenuation curve stored in the memory A sounding process for generating a sound based on the musical sound data,
Run
The characteristic of the attenuation curve is that the first attenuation amount from the first timing to the second timing after the first timing is less than the second attenuation amount from the second timing to the third timing after the second timing. The first characteristic and the third attenuation amount from the fourth timing after the third timing to the fifth timing after the fourth timing are the fourth attenuation values from the fifth timing to the sixth timing after the fifth timing. And a second characteristic that is not less than the amount of attenuation, the musical tone generated according to the first characteristic is attenuated when the first amplitude is greater than a certain level, and the first amplitude is at a certain level. A program that is executed so as to attenuate the musical sound generated according to the second characteristic when it is smaller.

200 electronic keyboard instruments,
210 CPU,
220 RAM,
230 ROM,
240 switch panel,
241 switch,
245 I / O interface,
250 LCD,
255 LCD controller,
260 keyboards,
261 key,
265 key scanner,
270 sound source LSI,
280 D / A converter,
290 amp.

Claims (7)

A keyboard with multiple keys,
A memory storing the tone data, and data indicating the characteristics of an attenuation curve for weakening the sound being produced based on the tone data, including muting according to the time elapsed after the key is released. ,
At least one processor,
Equipped with
The at least one processor is
A weakening instruction receiving process for receiving a weakening instruction including muffling for a sound being produced based on the tone data by detecting the key release;
An amplitude acquisition process for acquiring a first amplitude of the musical sound data to be output in response to the weakening instruction received by the weakening instruction receiving process,
Outputting the tone data with a second amplitude determined according to the first amplitude acquired by the amplitude acquisition processing by referring to data indicating the characteristics of the attenuation curve stored in the memory A sounding process for generating a sound based on the musical sound data,
Run
The characteristic of the attenuation curve is that the first attenuation amount from the first timing to the second timing after the first timing is less than the second attenuation amount from the second timing to the third timing after the second timing. The first characteristic and the third attenuation amount from the fourth timing after the third timing to the fifth timing after the fourth timing are the fourth attenuation values from the fifth timing to the sixth timing after the fifth timing. And a second characteristic that is not less than the amount of attenuation, the musical tone generated according to the first characteristic is attenuated when the first amplitude is greater than a certain level, and the first amplitude is at a certain level. If smaller, the musical sound generated according to the second characteristic is attenuated,
Electronic keyboard instrument. A determination process of determining the second amplitude based on the first amplitude and a key release speed detected in response to key release;
The electronic keyboard instrument according to claim 1, wherein in the sounding process, the musical sound data is output at the second amplitude determined by the determining process to generate a sound based on the musical sound data.   The electronic keyboard instrument according to claim 2, wherein the second amplitude determined by the determination process is smaller when the key release speed is higher than the first speed than when the key release speed is the first speed.   The characteristic of the attenuation curve is different between a characteristic of an attenuation curve in a lower range than a certain sound and a characteristic of an attenuation curve in a higher range than the certain sound. Electronic keyboard instrument described.   The electronic keyboard musical instrument according to any one of claims 1 to 4, wherein the characteristic of the attenuation curve is different for each set tone color. A keyboard with multiple keys,
A memory storing the tone data, and data indicating the characteristics of an attenuation curve for weakening the sound being produced based on the tone data, including muting according to the time elapsed after the key is released. ,
To the computer of the electronic keyboard instrument that has
A weakening instruction receiving process for receiving a weakening instruction including muffling for a sound being produced based on the tone data by detecting the key release;
An amplitude acquisition process for acquiring a first amplitude of the musical sound data to be output in response to the weakening instruction received by the weakening instruction receiving process,
Outputting the tone data with a second amplitude determined according to the first amplitude acquired by the amplitude acquisition processing by referring to data indicating the characteristics of the attenuation curve stored in the memory A sounding process for generating a sound based on the musical sound data,
Run
The characteristic of the attenuation curve is that the first attenuation amount from the first timing to the second timing after the first timing is less than the second attenuation amount from the second timing to the third timing after the second timing. The first characteristic and the third attenuation amount from the fourth timing after the third timing to the fifth timing after the fourth timing are the fourth attenuation values from the fifth timing to the sixth timing after the fifth timing. And a second characteristic that is not less than the amount of attenuation, the musical tone generated according to the first characteristic is attenuated when the first amplitude is greater than a certain level, and the first amplitude is at a certain level. A method of causing a musical sound to be generated according to the second characteristic to be attenuated when the musical value is smaller than the predetermined value. A keyboard with multiple keys,
A memory storing the tone data, and data indicating the characteristics of an attenuation curve for weakening the sound being produced based on the tone data, including muting according to the time elapsed after the key is released. ,
To the computer of the electronic keyboard instrument that has
A weakening instruction receiving process for receiving a weakening instruction including muffling for a sound being produced based on the tone data by detecting the key release;
An amplitude acquisition process for acquiring a first amplitude of the musical sound data to be output in response to the weakening instruction received by the weakening instruction receiving process,
Outputting the tone data with a second amplitude determined according to the first amplitude acquired by the amplitude acquisition processing by referring to data indicating the characteristics of the attenuation curve stored in the memory A sounding process for generating a sound based on the musical sound data,
Run
The characteristic of the attenuation curve is that the first attenuation amount from the first timing to the second timing after the first timing is less than the second attenuation amount from the second timing to the third timing after the second timing. The first characteristic and the third attenuation amount from the fourth timing after the third timing to the fifth timing after the fourth timing are the fourth attenuation values from the fifth timing to the sixth timing after the fifth timing. And a second characteristic that is not less than the amount of attenuation, the musical tone generated according to the first characteristic is attenuated when the first amplitude is greater than a certain level, and the first amplitude is at a certain level. A program that is executed so as to attenuate the musical sound generated according to the second characteristic when it is smaller.