JP2008299081A - Electronic musical instrument with sound board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make a low-frequency sound outline generated by a sound board clear, in an electronic musical instrument with a sound board. <P>SOLUTION: A digital signal processor (DSP) 25 including a reverberating circuit 30, inputs a signal which is input from right and left channels of a sound source 21 to the DSP 25, to a digital/analog converter (DAC) 26 by attaching a reverberation effect. A musical sound signal which is converted to an analog signal by the DAC 26 is input to speakers 7 to 12 for high sound and for middle high sound after passing high-pass filters 271 and 272. The musical sound signal which is output from the sound source 21 and mixed before passing the reverberating circuit 30, is input to a low-pass filter 273 through a sound board specific channel SBch as a low-frequency sound generator. A low-frequency sound component extracted by the low-pass filter 273 is amplified and input to a vibrator 6. The sound board 3 receives vibration generated by the vibrator 6 and vibrates with audible frequency and generates low-frequency musical sound. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an electronic musical instrument with a soundboard, and more particularly to an electronic musical instrument with a soundboard that is suitable for ensuring the intelligibility of a musical sound without imparting reverb to the musical sound generated by the vibration of the soundboard.

  In general, an electronic keyboard instrument detects a key depression state with a switch, calculates a detection result to generate a musical sound signal, and generates a sound by a speaker. However, an electronic musical instrument having a soundboard has been considered because the musical sound of a natural musical instrument cannot be better simulated only by pronunciation by a speaker. For example, Japanese Patent Laid-Open No. 53-69624 proposes an electric piano in which a plurality of vibrators are attached at positions along a string receiving piece of a soundboard in a conventional piano.

Japanese Patent No. 2917609 discloses a grand piano in which a soundboard divided into a high-frequency soundboard with a small area and a low-frequency soundboard with a large area are provided, and a soundboard drive unit is attached to each.
JP-A-53-69624 Japanese Patent No. 2917609

  A sound board provided in an electronic keyboard instrument has a relatively large area, and is often used to generate a low-pitched tone. On the other hand, a reverberation effect may be reproduced by giving a reverb signal to a musical sound signal. However, if this reverb signal is input to a vibration exciter that is a driving means for a low-range soundboard, the low-tone musical sound generated by the soundboard may be blurred and poor in clarity. Therefore, it has been a problem to improve the clarity of the musical sound generated by the soundboard provided for the low frequency range.

  The present invention provides an electronic musical instrument with a soundboard that solves the above-described problems and can clearly generate a low-frequency music sound from the soundboard without including a reverb signal in the sound signal that vibrates the soundboard. For the purpose.

  To achieve the above object, the present invention provides a sound source device that generates a musical sound signal in response to a keyboard operation, and a speaker and a soundboard as a sound system driven by the musical sound signal output from the sound source device. In the electronic musical instrument, the reverb applying means for applying reverb to the musical sound signal output from the sound source device, the vibrator attached to the soundboard, and the musical sound signal provided with reverb by the reverb applying means There is a first feature in that a circuit for inputting a musical sound signal that is input to a speaker and that is output from the sound source device to the exciter while avoiding a reverberating unit is provided.

  In addition, the present invention has a second feature in that the soundboard and the vibrator are for generating low sounds, and the speaker is for generating medium and high sounds.

  Furthermore, the present invention has a third feature in that the soundboard is attached to the rear surface of the upright electronic musical instrument main body through a soundboard frame attached to an edge of the soundboard.

  According to the present invention having the first feature, the exciter and the speaker are driven by the musical sound signal generated by the sound source device, and the musical sound is generated by the speaker, and the soundboard is vibrated by the exciter. Musical sound corresponding to the signal is generated. The musical sound signal input to the speaker is a signal to which reverberation, that is, a reverberation effect is imparted by the reverb imparting means, and the musical sound is accompanied by reverberation. On the other hand, since the musical tone signal that avoids the reverb applying means is input to the vibrator driven by the musical tone signal, the musical tone generated from the soundboard is not accompanied by reverberation. Therefore, the tone generated by the soundboard can be clearly defined. That is, in the case of a soundboard having a relatively large area, the reverb imparted to the sound signal and the reverberation generated as a characteristic of the soundboard may be mixed to blur the contour of the music sound. Blur can be prevented.

  According to the present invention having the second feature, apart from the musical sound generated by the soundboard, musical sounds of a high frequency range and a middle frequency range that are difficult to be generated by the soundboard are generated from the speaker to generate musical sounds in a wide frequency band. be able to.

  According to the present invention having the third feature, in the structure in which the soundboard is attached to the electronic musical instrument main body through the frame, the soundboard has a large area, so that a large sound pressure can be secured, but the outline of the musical tone is blurred. There is a noticeable tendency. According to the present invention, this inconvenience can be solved and the intelligibility of the musical tone can be increased.

  Hereinafter, the present invention will be described in detail with reference to the drawings. FIG. 1 is a rear view of an electronic piano which is an electronic musical instrument according to an embodiment of the present invention, and FIG. 2 is a right side view thereof. 1 and 2, the upright electronic piano 1 includes a main body 2 and a soundboard 3 attached to the rear surface of the main body 2. The sound board 3 is a horizontally long rectangular wooden board, and four sides are joined to the sound board frame 4. A plurality of (5 in this example) sounding bars 5 are attached to the sounding board 3. The sounding bar 5 has a function of instantaneously transmitting vibration to the entire sounding board 3 and a function of giving a desired strength to the sounding board 3. A vibrator 6 is fixed to the back surface of the soundboard 3, that is, the surface facing the inside of the electronic piano 1. The vibrator 6 is preferably, for example, a voice coil type in which a voice coil is disposed in a magnetic gap or a type using a piezoelectric element. The vibration exciter 6 is provided at a position deviated laterally and vertically from the center of the soundboard 3. If the exciter 6 is fixed to the central part of the soundboard 3, a sound that is extremely louder than other parts may be generated in a part of the sound range (center part), and the sound is not uniform. This is because if the angle of the plate 3 is excessively biased, a large amplitude cannot be given to the soundboard 3 and a desired sound pressure cannot be obtained.

  The specification of the vibrator 6 is set so that the soundboard 3 vibrated by the vibrator 6 is suitable for generating musical sounds in the low range. The upper part of the electronic piano 1 is provided with two left and right pairs of middle and high tone speakers 7, 8, 9 and 10 and a pair of left and right treble speakers 11 and 12. The middle and high tone speakers 7, 8, 9, 10 are arranged at the rear part of the electronic piano 1 and directed upward. This is to reproduce a state in which a musical sound is generated upward in a grand piano. The middle and high tone speakers 7, 8, 9, 10 are, for example, 7 cm full-range speakers. The high-frequency speakers 11 and 12 are, for example, 2 cm dome tweeters, and are arranged in front of the electronic piano 1, that is, toward the player.

  FIG. 3 is a diagram illustrating an example of a frequency band of a musical sound generated by a soundboard and a speaker. As shown in the figure, the soundboard 3 to which the exciter 6 is fixed covers a frequency band of 50 Hz or more and less than 180 Hz, and the mid-high speakers 7, 8, 9 and 10 cover 180 Hz or more and less than 6 kHz. The treble speakers 10 and 11 cover a frequency band of 6 kHz or more and less than 15 kHz. Note that the meanings of “low”, “medium / high”, and “high” of the musical sounds produced by the low-frequency vibrator 6, middle / high-frequency speakers 7, 8, 9, 10 and high-frequency speakers 11, 12 are relative to each other. The frequency bands of the musical tones generated by the middle and high tone speakers 7, 8, 9, and 10 are relatively higher than the frequency band of the musical tones generated by the vibrator 6, and the middle and high tone speakers 7, 8 , 19, and 10 means that the frequency band of the musical sound generated by the high-pitched speakers 11 and 12 is relatively higher than the frequency band of the musical sound generated at.

  FIG. 4 is a system configuration diagram of the electronic piano 1. The electronic piano 1 includes a CPU 13, a program memory 14, a musical tone waveform memory 15, a RAM 16, a panel interface circuit 17, a keyboard interface circuit 18, an automatic performance data memory 19, a disk interface circuit 20, and a tone generator 21.

  An operation panel display device 22 is connected to the panel interface circuit 17, a keyboard 23 is connected to the keyboard interface circuit 18, and a floppy disk drive (FDD) 24 is connected to the disk interface circuit 20. In addition, a digital signal processor (DSP) 25, a digital / analog converter (DAC) 26, a filter 27, and an amplifier 28 are connected to the sound source device 21 in series. The output of the amplifier 28 is connected to the sound system 29. The sound system 29 includes a soundboard 3 that is vibrated by the vibrator 6, middle and high tone speakers 7, 8, 9, 10 and high tone speakers 11, 12.

  The program memory 14 stores a program processed by the CPU 13, the musical sound waveform memory 15 stores musical sound waveform data, and the automatic performance data memory 19 stores automatic performance data. These memories 14, 15 and 19 can be constituted by ROM. The RAM 16 is a work area for temporarily storing various data when the CPU 13 executes the program, and a storage area for timbres and effects (such as reverb) set by operation of the operation panel display 22 and registration (such as reverb parameters). Used as.

  The operation panel display device 22 includes various switches such as a touch panel and a registration switch, a volume, and an indicator lamp such as an LED, and is disposed on a control panel provided adjacent to the keyboard 23, for example.

  FIG. 5 is a detailed view of a main part of FIG. In FIG. 5, the sound source device 21, DSP 25, and DAC 26 are each provided with a left channel Lch and a right channel Rch. Further, the DSP 25 and the DAC 26 have a soundboard dedicated channel SBch. The DSP 25 has a reverb circuit 30, which adds a reverb to the musical sound signal input from the sound source 21 and inputs it to the DAC 26. The output side of the left channel Lch of the DAC 26 is connected to the left high tone speaker 11 and the middle and high tone speakers 7 and 8 via the high pass filter 271 and the amplifier 281, and the output side of the right channel Rch of the DAC 26 is the high pass filter 272 and the amplifier. It is connected to the right treble speaker 12 and the middle and high tone speakers 9, 10 via 282.

  Also, the outputs of the left and right channels Lch and Rch of the sound source 21 are mixed before being input to the reverb circuit 30 and connected to the soundboard dedicated channel SBch of the DAC 26 via the soundboard dedicated channel SBch. The sound board dedicated channel SBch of the DAC 26 is connected to the vibrator 6 via the low pass filter 273 and the amplifier 283.

  Therefore, the tone signal to which the reverb effect is applied by the reverb circuit 30 is input to the channels Lch and Rch of the DAC 26. On the other hand, a tone signal without reverb is input to the sound board dedicated channel SBch of the DAC 26.

  FIG. 6 is a functional block diagram illustrating an example of a reverb circuit. This reverb circuit can be realized as a function of the DSP 25. The reverb circuit 30 includes a reflected sound generation unit 301 and addition units 302 and 303. The reflected sound generation unit 301 includes a delay circuit and an attenuation circuit, and delays and attenuates the input signal according to the reverb parameters (determining the reverb depth and attenuation time) input from the RAM 16, and adding units 302 and 303. To enter. The adder 302 adds the musical sound signal input from the left channel Lch of the sound source 21 and the reflected sound input from the reflected sound generator 301 and outputs the result as a left channel signal. Similarly, the adder 303 adds the musical sound signal input from the right channel Rch of the sound source 21 and the reflected sound input from the reflected sound generator 301 and outputs the result as a right channel signal.

  Note that the reverb circuit 30 is not limited to that shown in FIG. 6, and can include a localization control circuit and a circuit that makes the left / right channel mixing ratio variable.

  In the above configuration, the CPU 13 controls the tone generator 21 as a tone generator based on the program, the key information input from the keyboard 23 and the tone color, tempo, rhythm, etc. input from the operation panel display device 22. A musical sound signal is generated based on the waveform data read from the memory 15. In the automatic performance mode, automatic performance data stored in the automatic performance data memory 19 is used in place of the key information input from the keyboard 23.

  The tone signal generated by the tone generator 21 is input to the DSP 25. The DSP 25 applies a reverb effect to the musical sound signal input from the sound source device 21 by the reverb circuit 30. The parameters for applying the effect are supplied to the DSP 25 by an address instruction from the CPU 13. However, as described above, the reverb effect is not given to the mixing signal of the left and right musical sound signals input to the soundboard dedicated channel SBch.

  Both the musical sound signal after the reverb effect applied and the musical sound signal without the reverb effect output from the DSP 25 are converted into analog signals by the DAC 26. Among the output signals of the DAC 26, the output of the left channel Lch is input to the high pass filter 271 and the output of the right channel Rch is input to the high pass filter 272. The output of the soundboard dedicated channel SBch is input to the low pass filter 273. The high pass filters 271 and 272 extract middle and high pitch components of the input musical sound signal, and the low pass filter 273 extracts the input bass component.

  The output signal of the high-pass filter 271 is amplified by the amplifier 281 and input to the left high-frequency speaker 11 and the middle and high-frequency speakers 7 and 8. The output signal of the high-pass filter 272 is amplified by the amplifier 282 and input to the right treble speaker 12 and the middle and high tone speakers 9 and 10. The output signal of the low-pass filter 273 is amplified by the amplifier 283 and input to the vibration exciter 6 to generate a low tone.

  Thus, a musical sound is generated from the four speakers 7, 8, 9, 10 and the two high-frequency speakers 11, 12 by the musical sound signal, and the vibrator 6 is driven by the musical sound signal and is generated by the vibrator 6. The vibration is propagated to the soundboard 3 to generate a low tone.

  As described above, in an electronic musical instrument having a function capable of imparting reverb to a musical sound, a musical sound with reverb is generated only from a speaker, and reverb is applied to a musical sound generated by an exciter and a soundboard. It can be made not to grant. Therefore, it is possible to make the bass emitted from the soundboard clear.

  The present embodiment relates to the best mode of the present invention, and various modifications can be made without departing from the scope described in the claims. For example, the number of vibrators for generating low-range musical tones is not limited to one, and a single soundboard may be vibrated with a plurality of vibrators. The shape of the soundboard is not limited to a rectangle, and may be a simulation of the shape of a soundboard of a grand piano. Moreover, the shape, quantity, and arrangement of the treble speaker and the middle / high tone speaker are not limited to those in the embodiment, and can be variously selected.

  Further, the DSP 25 as the effector is shown in FIG. 5 as having only the reverb circuit 30, but the DSP 25 can be configured to give various effects to the musical sound signal. It is not prohibited to give to the musical tone signal input to 6. In short, it suffices if the musical tone signal provided with reverb is not input to the vibrator that vibrates the soundboard provided in the electronic musical instrument.

It is a rear view of the electronic piano which concerns on one Embodiment of this invention. It is a side view of the electronic piano which concerns on one Embodiment of this invention. It is a figure which shows the frequency band which the musical tone generated with a speaker and a sound board each covers. It is a block diagram which shows the system configuration | structure of the electronic piano which concerns on one Embodiment of this invention. It is a principal part detail drawing of a system configuration. It is a functional block diagram of a reverb circuit.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Electronic piano, 3 ... Soundboard, 4 ... Soundboard frame, 5 ... Soundboard, 6 ... Exciter, 7-10 ... Middle / high-frequency speaker, 11, 12 ... High-frequency speaker, 21 ... Sound source device, 25 ... DSP, 30 ... Reverb circuit

Claims (3)

In an electronic musical instrument having a sound source device that generates a musical sound signal in response to an operation of a keyboard, and a speaker and a soundboard as a sound system driven by the musical sound signal output from the sound source device,
Reverb providing means for applying reverb to the musical sound signal output from the sound source device;
A vibrator attached to the soundboard;
A circuit for inputting a musical sound signal to which reverberation has been imparted by the reverb imparting means to the speaker, and inputting a musical sound signal output from the sound source device to the exciter while avoiding the reverb imparting means. An electronic musical instrument with a soundboard.   2. The electronic musical instrument with a soundboard according to claim 1, wherein the soundboard and the vibrator are for generating low sounds, and the speaker is for generating middle and high sounds.   3. The electronic musical instrument with a soundboard according to claim 1 or 2, wherein the soundboard is attached to a rear surface of the upright electronic musical instrument main body through a soundboard frame attached to an edge of the soundboard. .

Images