KR100765006B1 - Electronic keyboard musical instrument - Google Patents

Abstract

An electronic keyboard musical instrument capable of realizing natural sound with good sound quality such as an acoustic piano is provided. The directing plate 33 is made of a plate-like member, and vibrates to generate sound. The first performance signal generator 22 generates the first performance signal based on the operation state of the plurality of keys in the keyboard 17. The second performance signal generator 23 generates a second performance signal separate from the first performance signal based on the operation of the plurality of keys and the operation of the pedal 18. The speakers 41A to 41D generate a musical sound based on the first performance signal generated by the first performance signal generator 22. The transducers 21A to 21C are attached to the sound board 33 to vibrate the sound board 33 based on the second performance signal generated by the second performance signal generator 23.

Acoustic Piano, Sound Plate, Keyboard, Pedal, Transducer

Description

Electronic keyboard musical instrument {ELECTRONIC KEYBOARD MUSICAL INSTRUMENT}

1 is a block diagram showing the overall configuration of an electronic keyboard musical instrument according to a preferred embodiment of the present invention.

2 is a plan view of the electronic keyboard musical instrument of FIG.

3A is a front view of the electronic keyboard musical instrument of FIG. 1;

FIG. 3B is a sectional view of one attachment portion to the frame of the facing plate in the electronic keyboard musical instrument of FIG. 1; FIG.

4 is a block diagram showing functions of the electronic keyboard musical instrument of FIG.

5 is a flowchart of main processing;

<Explanation of symbols for main parts of the drawings>

1: electronic keyboard instrument

17: keyboard

18: damper pedal

21: transducer

22: first performance signal generator

23: second performance signal generator

33: incense board

41: speaker

[Patent Document 1] Japanese Patent Application Laid-Open No. 7-92967

The present invention relates to an electronic keyboard musical instrument that generates a musical tone by vibrating a sound board.

Electronic keyboard musical instruments continue to be improved so that the musical sounds generated are close to natural musical notes with a sense of amplification, such as acoustic musical instruments, but they are still different from acoustic instruments.

This is because, in a natural musical instrument, not only the sound that is sounded by the vibration of a vibrating member such as a string, but also the touch sound of parts in the instrument by the operation of an operator such as a key, and the sound heard by resonating from each component and the facing plate are complicated. This is because there are many notes generated by the operation, and existing electronic keyboard instruments cannot sufficiently express such complex notes.

Electronic keyboard musical instruments are known that produce musical notes corresponding to the operator's or pedal's musical notes that must be generated according to the performance of the operation, and make the generated musical notes into performance sounds in the speaker, but the situation (operational state of the keyboard and pedals and their There is a limit in reproducing sound in a complicated operating environment due to operation timing).

On the other hand, an electronic keyboard musical instrument which is equipped with a speaker, which is equipped with a vibrating device on the incense plate, and which generates sound by the vibration of the incense plate in addition to the pronunciation by the speaker is also known. 92967).

However, in the electronic keyboard musical instrument of Japanese Patent Laid-Open No. 7-92967, the pronunciation of the speaker and the driving of the exciter are performed based on the same performance information generated according to the keying information. Therefore, in terms of faithfully reproducing the sound of performance by key depressing such as an acoustic piano, and the damper sound having a sense of expansion due to the resonance of strings other than the strings expressed at the time of damper pedal on operation, etc. There is room for improvement.

An object of the present invention is to provide an electronic keyboard musical instrument capable of realizing natural sound with good sound quality such as an acoustic piano.

In order to achieve the above object, according to an aspect of the present invention, it is made of a plate-shaped member, based on the operating state of the sound plate, a plurality of key operators, at least one pedal operator, the plurality of key operators to generate a sound by vibrating A first performance signal generator for generating a first performance signal, and a second performance signal for generating a second performance signal separate from the first performance signal based on the operation of the plurality of key operators and the operation of the pedal operator; A generator, at least one speaker for generating musical notes based on the first performance signal generated by the first performance signal generator, attached to the sound board, based on the second performance signal generated by the second performance signal generator There is provided an electronic keyboard musical instrument comprising at least one exciter to vibrate the facing plate.

According to the device according to the aspect of the present invention, it is possible to realize a natural sound with good sound quality such as an acoustic piano.

Preferably, the first performance signal is a signal for sounding a performance sound according to the pitch of the manipulated key operator, and the second performance signal is for sounding a damper sound corresponding to a resonance sound when the damper pedal on the acoustic piano is turned on. It is a signal for.

According to the apparatus according to the aspect of the present invention, the performance sound according to the presser operation is pronounced by the speaker, and the damper sound is pronounced by the facing plate, so that a more natural sound can be realized.

The above-mentioned objects, features and advantages of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings.

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

1 is a block diagram showing the overall configuration of an electronic keyboard musical instrument according to a preferred embodiment of the present invention. FIG. 2 is a plan view of the electronic keyboard musical instrument of FIG. 3A is a front view of the electronic keyboard musical instrument of FIG. 1, and FIG. 3B is a sectional view of a mounting portion to the frame of the facing plate in the electronic keyboard musical instrument of FIG.

As shown in FIG. 1, the electronic keyboard musical instrument 1 includes a detection circuit 3, a detection circuit 4, a ROM 6, a RAM 7, a timer 8, a display device 9, and a memory. The device 10, the external interface (external I / F) 11, the sound source circuit 13 and the effect circuit 14 are connected to the CPU 5 via the bus 16, respectively.

In addition, a performance operator 15 is connected to the detection circuit 3, and the performance operator 15 has a keyboard 17 composed of a plurality of keys for inputting pitch information and a damper pedal operated by foot. (Hereinafter referred to as a "pedal") 18 is included. The panel operator 2 including a plurality of switches for inputting various types of information is connected to the detection circuit 4. The display device 9 consists of a liquid crystal display (LCD) etc., and displays various information, such as a music score and a character. The timer 8 is connected to the CPU 5, and the external computing device 100 is connected to the external I / F 11. The sounding portion 20 is connected to the effect circuit 14 via the sound system 19. The sound system 19 includes a digital-to-analog converter (DAC), an amplifier, and the like.

The detection circuit 3 detects the operation state of the performance operator 15, and the detection circuit 4 detects the operation state of the panel operator 2. The CPU 5 is in charge of controlling the entire electronic keyboard musical instrument 1. The ROM 6 stores a control program executed by the CPU 5, various table data, and the like. The RAM 7 temporarily stores various input information such as performance data and text data, various flags, buffer data, calculation results, and the like. The timer 8 counts the interrupt time and various times in the timer interrupt processing. The storage device 10 stores various application programs including the above-described control program, various music data (performance data such as MIDI, audio data), various data, and the like.

The external I / F 11 includes a MIDI (Musical Instrument Digital Interface) I / F or various communication I / Fs. The external I / F 11 inputs MIDI signals from an external device such as the external player 100, and receives a MIDI signal. Output to an external device. The sound source circuit 13 converts the performance data, preset performance data, and the like input from the performance operator 15 into musical sound signals. The effect circuit 14 gives various effects to the sound signal input from the sound source circuit 13.

The storage device 10 includes, for example, a hard disk driver (HDD), but can record and read data to and from the external storage medium 12. Examples of the storage medium 12 include a flexible disk drive (FDD), a CD-R0M drive, a magneto-optical disk (M0) drive, and the like.

The sounding unit 20 includes a plurality (for example, four) speakers 41 (41A, 41B, 41C, 41D) and a plurality (for example, three) of transducers 21 (21A, 21B, 21C). It includes. The speaker 41 generates a musical sound based on each operation or performance data of the performance operator 15. The transducer 21 generates a sound by vibrating (exciting) the sound board 33 shown in FIG. 2 based on each operation or performance data of the pedal 18 and the keyboard 17. That is, in this electronic keyboard musical instrument 1, pronunciation is also performed by the vibration of the acoustic plate 33 in addition to the pronunciation by the speaker 41.

As shown in FIG. 3A, the pedal 18 is formed in the lower front part of the leg body 30, and the frame 31 is fixed to the upper part of the leg body 30. As shown in Fig. 2, the keyboard 17 is arranged on the player side (front side) like the grand piano. The facing plate 33 is disposed behind the keyboard 17. As shown in FIG. 2, the facing plate 33 has a shape seen from the same plane as the facing plate disposed below the string in the grand piano. The incense plate 33 is formed of a wood plate having a thickness of about 1 cm and has a uniform thickness, and the depth of the incense plate 33 is shorter on the high pitch side (right side of FIG. 2) than the low side (left side of FIG. 2). In addition, if it is suitable to vibrate and pronounce, the material and thickness of the facing plate 33 may be appropriately changed in the design.

Although the shape seen from the plane of the frame 31 is not shown in figure, it has a frame shape which looked at the edge part of the facing plate 33 substantially. Specifically, the outer edge of the frame 31 is slightly smaller than the periphery of the facing plate 33 and has a similar shape with respect to the facing plate 33. As shown in FIG. 3B, the facing plate 33 is fixedly held on the upper end of the frame 31 through the rubber plate making member 32 with a plurality of screws 34 at appropriate intervals. It is preferable to employ | adopt the thing with high cushioning function which does not transmit the vibration of the facing plate 33 to the square body 30 as the rubber plate-making member 32. As shown in FIG.

Above the incense plate 33, an opening / closing lid 42 capable of opening and closing as in an acoustic grand piano is formed. In FIG. 2 and FIG. 3A, the cover open state of the opening / closing cover 42 is shown. By opening / closing the lid 42 at the time of performance, the pronunciation of the speaker 41 and the facing plate 33 is effectively soundproofed.

Speakers 41A and 41D are disposed at both ends of the left and right immediately behind the keyboard 17. The speakers 41B and 41C are fixed to an unshown stay fixedly formed with respect to the frame 31 and are disposed below the facing plate 33. As shown in FIG. 2, the speaker 41B is disposed at the position of the rear half of the sound board 33 as the middle-note to low-note side in plan view, and the speaker 41C is provided. Is located at the position of the front portion of the facing plate 33 as the high-note side.

The transducers 21A, 21B, 21C are disposed on the upper surface of the facing plate 33 spaced apart from each other. The transducer 21A is disposed on the bass side of the incense plate 33, the transducer 2lB is disposed on the low range of the incense plate 33, and the transducer 21C is short in the depth of the high side of the incense plate 33. Is placed in the area. As for the position of the front-back direction, the transducer 21C is located in front and the transducer 21B is located in the rearmost. Each transducer 21A, 21B, 21C is disposed at a position capable of efficiently vibrating the facing plate 33 at a relatively large natural frequency in a frequency band that can be generated in a keyboard musical instrument. That is, each transducer 21 not only avoids the screw 34 position and the frame 31 position, but also tangent at each natural frequency generated when freely vibrating the sound plate 33 while slowly changing the frequency. lines are placed at a lower density.

Each transducer 21 can be attached directly to the facing plate 33. Regarding the attachment to the facing plate 33, any means such as screwing and sticking can be used. The structure of the transducer 21 is a known structure as described in FIGS. 1 and 2 of “Radio Technology” March 1971, page 266. It vibrates by an electric signal (playing signal or driving signal), and Vibration of the facing plate 33 by the reaction by the weight of the. The transducer 21 may be any structure as long as the transducer 21 is capable of vibrating and pronounced the facing plate 33 based on an electrical signal.

In this preferred embodiment, the transducers 21A and 21B use the same configuration. The transducers 21A and 21B are large, have a low frequency band, have a particularly good vibration efficiency in the vicinity of the frequency of 250 Hz, and generate very little vibration at higher frequencies. In addition, the strength of vibrations that can be generated is strong, and mainly responsible for the pronunciation of the low range.

On the other hand, the transducer 21C differs from the transducers 2lA and 21B in characteristic (capacity), that is, vibration efficiency with respect to the input signal. The transducer 21C is smaller than the transducers 21A and 21B, has a high frequency band, and has good vibration efficiency at a frequency of 1000 Hz or more. In addition, the intensity of vibration that can be generated is not as strong as the transducers 21A and 21B, and is mainly responsible for pronunciation of the high range.

4 is a block diagram showing the function of the electronic keyboard musical instrument 1. The signal processor 40 shown in this figure includes first and second performance signal generators 22 and 23, first and second performance data 24 and 25, adders 36 and 37, and an effect processor 26. ), A delay processor 27, an SP output divider 28, a TR output divider 29, and the like as functional units. These functions of the respective functional units of the signal processing unit 40 include the CPU 5, the ROM 6, the RAM 7, the timer 8, the storage device 10, the external interface 11, This is realized by a combination of components including the sound source circuit 13, the effect circuit 14, the sound system 19, and the like.

The first performance data 24 are waveform data sampled for each pitch of the sound to be pronounced when each key is operated without pressing the damper pedal in the acoustic grand piano. On the other hand, the second performance data 25 is waveform data obtained by subtracting the data corresponding to the first performance data 24 from sampling the pitch of the sound to be pronounced when each key is operated while pressing the damper pedal. That is, the first performance data 24 are data for reproducing the normal performance sound. The second performance data 25 is data for reproducing a damper sound with a sense of enlargement caused by resonance of strings other than the strings generated when the damper pedal is operated in the acoustic piano. These are stored in the ROM 6, for example.

The first performance signal generator 22 generates the first performance signal using the first performance data 24 in accordance with a key pressing / releasing operation of each key of the keyboard 17, and adds ( 36 to effect processor 26. On the other hand, the second performance signal generator 23 generates the second performance signal using the second performance data 25 in accordance with the operation of the pedal 18 and the keyboard 17, and generates the buffer and adder 37. To the delay processor 27. The first performance signal is for sounding the speaker 41 and the second performance signal is for driving the transducer 21, both of which differ in characteristics.

When the first and second audio signals 43 and 44 are input, the first audio signal 43 is sent to the effect processor 26 via a buffer and adder 36, and the second audio signal 44 is It is sent to the delay processor 27 via the buffer and adder 37.

Here, the first and second audio signals 43 and 44 are signals stored in the storage device 10 or input from the external player 100, and audio data of a plurality of tracks (for example, 2). The signal whose source is. The first audio signal 43 is a signal for reproducing a normal playing sound and corresponds to the first playing signal in real time playing. The second audio signal 44 is a signal for reproducing a damper sound and corresponds to a second performance signal in real time performance. The audio data is data for reproducing the normal sound and the damper sound, which are prepared in advance.

The first audio signal 43 and the first performance signal sent to the effect processor 26 are effected by the effect processor 26 and supplied to the SP output divider 28, and the buffer and adder ( It is also sent to the delay processor 27 via 36. On the other hand, the second performance signal sent to the delay processor 27, the second audio signal 44, and the signal transmitted from the effect processor 26 are subjected to a predetermined delay process in the delay process 27, so that the TR output divider 29 Is supplied.

The SP output divider 28 distributes the output to the speaker 41 based on the signals (first performance signal, first audio signal 43) supplied from the effect processor 26. That is, signals are distributed and amplified to each of the speakers 41A to 41D. At this time, the output is made in accordance with the pitch and speed defined by the signal, but for sound field localization, each speaker 41 matches the pitch of the operated key or the pitch defined by the first audio signal 43. The distribution of output to) is set.

The TR output divider 29 distributes the output to the transducer 21 based on the supplied signal (second performance signal, second audio signal 44, and the like). That is, for each of the transducers 21A, 21B, 21C, an analog drive signal is generated, amplified and output. Specifically, a drive signal that vibrates at an intensity according to the frequency and speed according to the pitch defined by the signal is generated / output for each of the transducers 21A, 21B and 21C.

5 is a flowchart of main processing. This process is started at power on.

First, initialization is executed, that is, execution of a predetermined program is started, and initial settings are performed by setting initial values in various registers such as the RAM 7 (step S101). Next, the input of the panel operator 2 is confirmed (step S102), and the setting (volume, timbre, effect setting, automatic performance execution availability, etc.) of the apparatus corresponding to the input is performed (step S103). Then, it is determined whether there is an input of the playing operator 15 (step S104). If there is no input, the flow advances to step S105, and if there is an input, it indicates a key pressing instruction (the key 17). The key is pressed) (step S106).

As a result of the determination, it is determined whether it is a key releasing instruction (step S110) if it is not an instructing command (step S110), and if it is not an instruction, it is determined whether or not the pedal 18 is on (step S113). If the pedal 18 is not turned on, the pedal 18 is turned off, and the flow advances to step S115. Therefore, when the input of the performance operator 15 is an indentation instruction, steps S107 to S109 are executed, and when this is an instruction, steps S111 and S112 are executed. If the input is the on operation of the pedal 18, step S114 is executed. If the input of the pedal 18 is the off operation, step S115 is executed to proceed to step S105, respectively.

First, in step S107, it is determined whether or not the pedal 18 is currently on. If the pedal 18 is not in the on state, the flow advances to step S109 to read the first performance data 24 corresponding to the pitch of the keystroke key (the keyed key) from the ROM 6 to read the first performance data ( Based on 24), a first playing signal having an envelope according to the pressed key velocity is generated. On the other hand, when the pedal 18 is in the on state, the flow advances to step S108 to read the second performance data 25 according to the pitch of the keystroke key, and to generate a second performance signal having an envelope according to the speed of the dryness. Step S109 is executed.

In step S111, it is determined whether the pedal 18 is currently in an on state. If the pedal 18 is not in the on state, the flow advances to step S112 to stop the playing signal of the key (which is the key). That is, a signal for noise is generated in order to process noise of the corresponding sound in sound. In this process, the first performance data 24 is read out to generate a first performance signal for noise having an envelope according to the operation. On the other hand, when the pedal 18 is in the on state, the process proceeds to step S105 without stopping the performance signal.

In step S114, when there is a sound being pronounced as the pressed state, a second performance signal corresponding to the key in the pressed state is generated according to the on operation of the pedal 18. That is, the second performance data 25 in accordance with the pitch of the key in the pressed state is read out to generate a second performance signal having an envelope consistent with the sound attenuation state during the pronunciation process.

In step S115, when there are notes being pronounced at corresponding pitches other than the keys in the pressed state, the performance signals corresponding to them are stopped. That is, a signal for noise is generated in order to process noise of the corresponding sound in sound. In this process, the first performance data 24 and the second performance data 25 corresponding to the pitch being pronounced are read as the corresponding pitch other than the key in the pressed state, and the envelope according to the off operation of the pedal 18 is read. A first performance signal and a second performance signal for the noise to be generated are generated.

In step S105, a signal is output to each speaker 41 and each transducer 21 based on the generated 1st performance signal and 2nd performance signal. In addition, when execution of automatic performance is permitted and the 1st and 2nd audio signals 43 and 44 are input, the output based on these signals is performed. In some cases, the output based on the first and second performance signals and the first and second audio signals 43 and 44 may be performed in parallel.

That is, in step S105, first, based on the generated first performance signal, the signal is distributed and output to each speaker 41 so as to be in the position according to the pitch at the output level according to the first performance signal. The same process applies to the case where the first audio signal 43 is input. By these, the normal playing sound according to the apical and / or audio data is pronounced from the speaker 41.

In step S105, the drive signal is generated and output individually in consideration of the characteristics and arrangement of the transducers 21 so as to be in the position according to the pitch based on the generated second performance signal. Even when the second audio signal 44 is inputted, the same processing is performed. As a result, a sound of damper sound according to the pressure gun and / or the audio data is generated. Thereafter, the flow returns to step S102.

Compared to the sound produced by the speaker 41, the sound caused by the vibration of the acoustic panel 33 is closer to the reproduction of the pronunciation in a complicated operating environment by the operation state of the keyboard 17 and the pedal 18 and their operation timing. And natural sound with good sound quality. In particular, since the facing plate 33 is shaped like the facing plate of a grand piano, its sound is also close to that of an acoustic piano. In particular, since the plan view of the frame 31 is a frame shape that almost looks at the periphery of the facing plate 33, the facing plate 33 can vibrate largely (at a sufficiently low frequency) in the inner region of the frame 31. Thus, the damper sound in the low range can be satisfactorily reproduced. Moreover, since the transducer 21 is arrange | positioned in the position which can vibrate the facing plate 33 efficiently, sufficient sounding amount can be obtained.

Here, it is assumed that the balance between the output level (volume) of the performance sound by the first performance signal and the output level of the damper sound by the second performance signal is fixed in advance. However, the present invention is not limited thereto, and the balance of the two may be different depending on the set output level. For example, as the setting of the output level is increased, the degree to which the output level at the performance sound side is higher than that of the damper sound may be increased.

According to a preferred embodiment, the speaker 41 pronounces the playing sound by the first playing signal generated according to the operation of the keyboard 17, and the second sound generated by the operation of the pedal 18 and the keyboard 17. Since the transducer 21 is driven by the performance signal and the sound board 33 pronounces the damper sound, it is possible to realize a natural sound with good sound quality such as an acoustic piano.

In addition, since the facing plate 33 is shaped like the facing plate of the grand piano, a natural sound close to the grand piano is realized. In particular, when the plate is vibrated to pronounce low sounds, a large area is required as compared to high-pitched sounds, so that the shape of the facing plate 33 is ideal for reproducing piano sounds.

When the first performance signal generator 22 generates the first performance signal, the distribution to the speakers 41A to 41D may be determined. For example, in the first performance signal, waveforms for the left and right channels are read from the first performance data 24 and generated as stereo signals for the left and right channels. The left channel signal may be pronounced by the speakers 41A and 41B, and the right channel signal may be pronounced by the speakers 41C and 41D. In this case, the speaker 41A and the speaker 41B, the speaker 41C, and the speaker 41D have their characteristics different from each other, and pass a signal for the left channel (or the right channel) through a filter to obtain an appropriate value. It may be pronounced as a signal. In addition, the speaker 41 may have two specifications instead of four (for example, only the speaker 41A and the speaker 41D).

Similarly, when generating the second performance data 25 in the second performance signal generator 23, the distribution to the transducers 21A to 21C may be determined. The number of the transducers 21 may not be three but only two, for example, the transducers 21A and 21B. In that case, contrary to the example of FIG. 2, the left transducer 21A is disposed on the depth side, and the right transducer 21B is disposed on the front side. Similarly to the above, in the second performance signal, waveforms for the left and right channels are read out from the second performance data 25 to be generated as stereo signals for the left and right channels, and the transducers are signals for the left channel. While driving 21A, the transducer 21B may be driven by a signal for the right channel.

In this preferred embodiment, in order to reproduce the piano sound more appropriately, the facing plate 33 is made into the shape of the facing plate of the piano, but the shape of the facing plate 33 may be any shape in terms of simply sounding, and more appropriate sound. In order to pronounce the sound, the sound may be appropriately adopted depending on the type of sound to be pronounced. For example, when the violin sounds are reproduced, ideal pronunciation can be expected.

In this preferred embodiment, the second performance signal generated by the second performance signal generator 23 (refer to FIG. 4) is a signal for sounding a damper sound, but is not limited thereto. It may be generated for various sound effects that can be realized by pronunciation. In that case, you may make it generate the signals for these effect control according to operation of pedals other than the damper pedal 18. FIG.

In addition, although the 2nd performance signal was produced using the 2nd performance data 25, it is not limited to this, You may use the 1st performance data 24. FIG. In this case, by processing the waveform by reading the first performance data 24, a waveform of a pseudo damper sound separate from the first performance signal may be generated, which may be used as the second performance signal.

When the second performance signal generator 23 generates the second performance signal in accordance with the operation of the pedal 18, not only the pedal 18 is turned off but also the change of the operation of the pedal 18 (the damper is completely in the strings). The second performance signal may be generated in consideration of the pronunciation in the half-contact state, etc.) from the state in which it is in contact with each other to the distance from the state of contact.

In this preferred embodiment, the transducer 21 is attached to the upper surface of the facing plate 33, but may be attached to the lower surface. The transducers 21A and 21B may have different characteristics. The number of the transducers 21 may be at least one as long as the number of the transducers 21 is simply pronounced, but from the viewpoint of obtaining good sound quality, it is preferable to form at least two or more, or four or more.

According to the present invention, it is possible to provide an electronic keyboard musical instrument capable of realizing natural sound with good sound quality such as an acoustic piano.

Claims (2)

As an electronic keyboard musical instrument, The sound board which consists of a plate-shaped member and generate | occur | produces a sound sound by vibrating, Multiple key operators, At least one pedal operator, A first playing signal generator for generating a first playing signal based on an operation state of the plurality of key operators; A second performance signal generator for generating a second performance signal separate from the first performance signal based on the operation of the plurality of key operators and the operation of the pedal operator; At least one speaker that generates musical notes based on the first performance signal generated by the first performance signal generator, At least one vibrator attached to the framing plate to vibrate the framing plate based on a second performance signal generated by the second performance signal generator; Electronic keyboard musical instrument comprising a. The method of claim 1, The first performance signal is a signal for sounding a performance sound according to the pitch of an operated key operator, and the second performance signal is a signal for sounding a damper sound corresponding to a resonance sound when a damper pedal is turned on in an acoustic piano. Electronic keyboard musical instrument.

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