JP4327734B2 - Acoustic system - Google Patents

Description

  The present invention relates to an acoustic system for artificially generating a resonance sound of an acoustic instrument based on a musical sound signal.

  2. Description of the Related Art Conventionally, a method for generating a musical sound signal based on a previously recorded acoustic instrument sound and outputting the musical sound signal from a plurality of speakers is known. However, since the speaker has a small vibrating body area and is a point sound source, even if a plurality of speakers are arranged, the vibrating body vibrates in a wide range in order and resonates with each other to generate a resonance sound like an acoustic instrument. It was impossible to generate.

Therefore, in order to solve the above problem, an actuator is attached to one point of the casing of the electronic musical instrument, and a musical sound signal is input to this actuator to vibrate a part of the casing as a diaphragm. Electroacoustic transducers have been proposed that add the same acoustic characteristics as a musical instrument diaphragm and obtain an acoustic output that approximates an acoustic instrument. (See, for example, Patent Document 1).
JP-A-8-1111896

  However, in the above electroacoustic transducer, although a part of the casing of the electronic musical instrument is used as a diaphragm and the diaphragm is vibrated, only one diaphragm vibrates, and an actual acoustic instrument In this case, it is difficult to reproduce the resonance sound generated by resonating the strings, the diaphragm, the case, and the like. Further, since a part of the casing is used as a diaphragm, the position, angle, shape, etc. of the diaphragm are constant, and the diaphragm cannot be arranged in the same manner as an actual acoustic instrument.

  The present invention has been made in view of these problems, and in a sound system for artificially generating resonance sound of an acoustic instrument, by using a plurality of diaphragms, resonance sound closer to the sound of the acoustic instrument can be generated. The purpose is to do so.

  The invention according to claim 1, which has been made to achieve such an object, includes a plurality of diaphragms each having at least one actuator attached to one side thereof, and is driven by a musical sound signal input from the outside, An acoustic system that artificially generates a resonance sound of an acoustic instrument by vibrating each diaphragm, and is input to an actuator of each diaphragm according to an angle formed by the plate surfaces of each diaphragm. And a phase control unit for controlling the phase of the musical sound signal.

  In the acoustic system of the present invention configured as described above, each diaphragm can be arranged at any position and angle, and the phase of the musical sound signal input to the actuator according to the angle formed by the diaphragm surfaces of each diaphragm. Can be controlled. For this reason, by controlling the vibrations of multiple diaphragms for each diaphragm and oscillating them in an optimal phase state, it is possible to create a more complex resonance state by resonating with each other. It becomes possible to approach the sound.

Next, the invention according to claim 3 is the acoustic system according to claim 1 or 2 , wherein the diaphragm forms one surface of the housing. In this way, the vibration of the diaphragm is transmitted to the air in the bag, and the air vibration in the instrument of the acoustic instrument can be simulated by this air vibration, and a complex resonance sound can be generated.

The invention described in Claim 1, as a vibration plate of the multiple, comprises two diaphragm mounting surface of the actuator is arranged so as to face the same direction, the phase control unit, the actuator of the diaphragm The phase of the musical sound signal input to each actuator is controlled so that the input musical sound signals are in phase with each other.

  In this way, vibrations having the same phase are transmitted to the diaphragm arranged so that the mounting surface of the actuator faces in the same direction. Therefore, the vibration of one diaphragm is caused by two diaphragms arranged at free positions. It is possible to simulate the state, and it is possible to generate a broader resonance sound by causing each other to resonate rather than simply vibrating one diaphragm.

On the other hand, the invention described in claim 2, as the diaphragm of multiple, comprises two diaphragm mounting surface of the actuator is arranged in parallel with each other to face each other, the phase control unit, the actuators of the diaphragms The phase of the musical sound signal input to each actuator is controlled so that the musical sound signal input to is in reverse phase.

  In this way, vibrations in opposite phases are transmitted to the two diaphragms arranged in parallel so that the mounting surfaces of the actuator face each other, so one vibration is generated by the two diaphragms arranged at free positions. The vibration state of the plate can be simulated, and a broader resonance sound can be generated by resonating each other than simply vibrating one diaphragm.

According to a fourth aspect of the present invention, in the acoustic system according to any one of the first to third aspects, the two diaphragms have different areas.
In this way, low frequency low frequency sounds can be generated mainly with a large area diaphragm, and high frequency high sounds can be generated mainly with a small area diaphragm. And can generate sound in a wider range.

Here, the diaphragm of the acoustic system of the present invention may be made of metal or resin, but preferably comprises a wooden soundboard as described in claim 5 . By doing so, it is possible to generate a resonance state like an acoustic piano using a wooden soundboard.

Further, the diaphragm of the acoustic system of the present invention may be disposed anywhere, but as described in claim 6 , it is preferable that the diaphragm is disposed inside the electronic musical instrument. In this way, since the sound system is housed inside the electronic musical instrument, when the electronic musical instrument is played, it is possible to obtain a sense that the musical instrument plays a sound.

Further, an invention according to claim 7, in the audio system of claim 1, the acoustic system, which artificially generates a resonance sound of the piano based on a musical tone signal of an electronic piano, the diaphragm Is a wooden soundboard and disposed inside the electronic piano, the actuator is attached to one end of the diaphragm, and the first diaphragm, which is one of the two diaphragms, has an actuator mounting surface on the electronic piano The second diaphragm, which is the other diaphragm, is placed on the upper front plate so that the actuator is on the right side. It is arranged on the back side and has a smaller area than the first diaphragm.

  In this way, a bass musical sound signal input from the actuator on the first diaphragm arranged in the lower left part vibrates the first diaphragm having a larger area, thereby generating a wider bass. The treble tone signal input from the actuator on the second diaphragm disposed on the upper right side vibrates the second diaphragm having a smaller area, thereby generating a broader treble, Since the diaphragm is arranged vertically, the sound board is arranged vertically, and it is possible to simulate the resonance state of an upright piano in which a bass part is played on the left side of the keyboard and a treble part is played on the right side.

On the other hand, according to an eighth aspect of the present invention, in the acoustic system according to the second aspect , the acoustic system artificially generates a resonance sound of a piano based on a musical sound signal of an electronic piano. Is a wooden soundboard and disposed inside the electronic piano, the actuator is attached to one end of the diaphragm, and the first diaphragm, one of the two diaphragms, is the actuator of the first diaphragm. The mounting surface faces the inside of the electronic piano, and the actuator is placed horizontally on the top of the shelf so that the actuator is on the left side. It is arrange | positioned at the lower part, and an area is smaller than a 1st diaphragm, It is characterized by the above-mentioned.

  In this way, the bass tone signal input from the actuator on the first diaphragm located in the lower left part vibrates the first diaphragm having a large area, thereby generating a wide bass more effectively. The high tone signal input from the second actuator arranged in the upper right part can be vibrated by the second diaphragm having a small area, thereby generating a high tone more effectively. Since each diaphragm is arranged horizontally, the sound board is arranged horizontally, and it is possible to simulate the resonance state of a grand piano that plays a bass part on the left side of the keyboard and a treble part on the right side.

Embodiments of the present invention will be described below with reference to the drawings.
[First embodiment]
First, an example in which the acoustic system of the present invention (specifically, the invention described in claim 10) is applied to a grand piano type electronic piano will be described.

  FIG. 1 is a perspective view of a grand piano type electronic piano 40 according to the present embodiment, FIG. 2 is a front view of the grand piano type electronic piano 40 according to the present embodiment, and FIG. It is a block diagram which shows the sound generation part 22 arrange | positioned, Fig.3 (a) is an exploded view, FIG.3 (b) is a trihedral view.

  As shown in FIG. 1, in the electronic piano 40 of the present embodiment, the first sound generating unit 22a and the second sound generating unit 22b are disposed inside a grand piano type case 46 having a keyboard 12 composed of a plurality of keys. A control device 30 that generates a musical sound signal in response to pressing and release of the two sound generating units 22 and the keys constituting the keyboard 12 and outputs the musical sound signal to the sound generating unit 22 (however, the control in the figure) The device is omitted).

  Each sound generator 22 (specifically, 22a and 22b) includes a rectangular soundboard 26 (26a and 26b) and one end side in the long side direction of the soundboard 26 as shown in FIG. The actuator 24 (24a, 24b) is screwed at one point (not shown in the figure), and a rectangular parallelepiped wooden box 28 (28a, 28b) with one surface open. The box 28 is formed in such a size that the opening surface fits the soundboard 26. And as shown in FIG.3 (b), the sound board 26 is attached to the opening surface of the box 28 so that the actuator 24 may be settled inside the box.

  As shown in FIGS. 1 and 2, the first sound generator 22 a configured as described above has a first soundboard 26 a (shaded portion in FIG. 1) below the shelf 44. When the electronic piano is viewed from the front, the long side direction of the first soundboard 26a is the width direction of the case 46, and the first actuator 24a is horizontally fixed in the case 46 so as to be on the left side. The long side of the first soundboard 26 a is formed to be slightly smaller than the width of the case 46 so that the first sound generator 22 a can be accommodated in the case 46.

  On the other hand, the second sound generator 22b has a long side of the second sound board 26b when the second sound board 26b (shaded part in FIG. 1) faces upward at the bottom of the roof 42 and the electronic piano is viewed from the front. The direction is the width direction of the case 46, and the second actuator 24 b is horizontally disposed so as to be on the right side, and is fixed in the case 46. And the long side of the 2nd sound board 26b is formed in the length substantially the same as the long side of the 1st sound board 26a, and a short side becomes shorter than the length of the 1st sound board (for example, 1/3 times). It is formed as follows. Further, the depth of each box 28 constituting each sound generator 22 is set to a length that can be accommodated in the case 46 when the first sound generator 22a and the second sound generator are arranged as described above. Each is formed.

  In addition, the 1st sound board 26a and the 2nd sound board 26b of a present Example are respectively corresponded to the 1st diaphragm and the 2nd diaphragm of this invention. In this embodiment, the actuator 24 employs an electro-mechanical vibration converter that can convert an electrical signal of, for example, 20 Hz to 15000 Hz into mechanical vibration by magnetic interference.

FIG. 4 is a configuration diagram illustrating the control device 30 of the electronic piano according to the present embodiment.
As shown in FIG. 4, a control device 30 for controlling the electronic piano of this embodiment connects the CPU 4, a RAM 6 used as a work area as appropriate, and a ROM 8 storing a control program. The microcomputer is composed of a bus 2 for the purpose. The bus 2 is connected to a DSP 10 for processing a musical tone signal, a sound source 14 storing the musical tone signal, and a D / A converter 16 for converting the digital musical tone signal into an analog musical tone signal. ing.

  Here, the CPU 4 executes the control program stored in the ROM 8 using the RAM 6 as a work area, and from the sound source 14 in accordance with key depression / release of each key constituting the keyboard 12 connected to the bus 2. While reading the musical tone signal, the DSP 10 processes the musical tone signal and outputs it to the D / A converter 16.

  The tone signal converted into an analog signal by the D / A converter 16 is amplified to an appropriate magnitude by the amplifier 18 and then input to the phase controller 20, via the phase controller 20. Are input to the actuator 24 of each sound generator 22. The musical tone signal input to the actuator 24 is converted into vibration, and the vibration is transmitted to the entire soundboard 26 to be output as sound.

FIG. 5 is an explanatory diagram showing the phase control of the musical sound signal by each phase control unit 20 of the electronic piano of this embodiment.
Each phase control unit 20 controls the phase of the input musical sound signal so that the phase difference of the musical sound signal input to each actuator 24 is always constant. As shown in FIG. 5, when the phase shift amount of the first phase control unit 20a is α and the phase shift amount of the second phase control unit 20b is β, β = α + 180 ° is set. The unit 20a and the second phase control unit 20b control the phase of the musical tone signal so that the phase difference of the musical tone signal is always 180 degrees, and output it to the first actuator 24a and the second actuator 24b, respectively. For this reason, the first and second actuators 24a and 24b are inputted with the sound signals having the opposite phases by 180 degrees and the vibrations having the opposite phases are transmitted from the actuators 24 to the soundboards 26, respectively.

  As described above, in the electronic piano of the present embodiment, the two sound generating units 22 are mounted in the case 46 of the grand piano type electronic piano, and the first sound board constituting the sound generating unit 22 is provided. 26a and the second soundboard 26b are opposed to each other (the angle between the plate surfaces is 180 degrees), the first soundboard 26a faces the mounting surface of the first actuator 24a toward the inside of the electronic piano, and the electronic piano is When viewed from the front, the first actuator 24a is placed horizontally on the top of the shelf 44 of the electronic piano so that it is on the left side, and the second soundboard 26b is on the roof 42 so that the second actuator 24b is on the right side. It is arranged at the bottom of. The tone signal input to each actuator 24 is controlled by the phase controller 20 so as to have an opposite phase.

  For this reason, since these two soundboards 26 facing each other vibrate in opposite phases, it is possible to simulate a state in which one soundboard vibrates, rather than simply vibrating one soundboard. Can resonate with each other to generate a broader sound, and the actuators 24 are located away from each other, so that vibrations are generated from two distant places and the sound is output in stereo.

  Then, the low tone signal input from the first actuator 24a arranged at the lower left part vibrates the first soundboard 26a having a large area, so that the first sound generating unit 22a can more effectively. A wide bass sound is generated, and a high tone music signal input from the second actuator 24b arranged in the upper right part vibrates the second soundboard 26b having a small area, thereby causing the second sound generator 22b to vibrate. As a result, a high pitched sound is generated more effectively.

Further, since each soundboard 26 is horizontally arranged, the soundboard is horizontally arranged, and the resonance state of a grand piano that plays a bass part on the left side of the keyboard and a treble part on the right side can be simulated.
On the other hand, since the wooden soundboard 26 constitutes one surface of the wooden box 28, the vibration of the soundboard 26 is transmitted to the air in the box, and this air vibration simulates the air vibration inside the piano of the acoustic piano. In addition, more complex resonance can be generated.

Since the resonance sound is generated from the inside of the case 46, the user of the electronic piano can obtain a sense that the musical instrument is playing a sound.
[Second Embodiment]
Next, an example in which the acoustic system of the present invention (specifically, the invention described in claim 9) is applied to an upright piano type electronic piano will be described.

  6 is a perspective view of the upright piano type electronic piano 50 of the present embodiment, FIG. 7A is a front view of the upright piano type electronic piano 50 of the present embodiment, and FIG. 7B is the present embodiment. The side view of the example upright piano type electronic piano 50, FIG. 8 is explanatory drawing which shows the phase change by the phase control part 20 of the electronic piano of a present Example.

  As shown in FIG. 6, in the electronic piano 50 of the present embodiment, the first sound generator 22a is provided in the upright piano type case 56 having the keyboard 12 composed of a plurality of keys, as in the first embodiment. Control for generating a musical sound signal in response to key depression and release of the two sound generating units 22 of the second sound generating unit 22b and each key constituting the keyboard 12, and outputting the musical sound signal to the sound generating unit 22 A device 30 (however, the control device is omitted in the figure) is mounted.

  In this embodiment, each sound generator 22 is configured in the same manner as in the first embodiment, and the first sound generator 22a is located behind the lower front plate 54 as shown in FIGS. The first soundboard 26a (shaded portion in FIG. 6) is located on the near side, and when the electronic piano is viewed from the front, the long side direction of the first soundboard 26a is the width direction of the case 56, and the first actuator 24a Is fixed in the case 56 vertically to the rear of the lower front plate 54 so as to be on the left side. The long side of the first soundboard 26 a is formed to be slightly smaller than the width of the case 56 so that the first sound generator 22 a can be accommodated in the case 56.

  On the other hand, the second sound generating unit 22b has a second soundboard when the second soundboard 26b (shaded portion in FIG. 6) is located behind the upper front plate 52 and the electronic piano is viewed from the front. The case is such that the long side direction of 26b is the width direction of the case 56, the second actuator 24b is arranged vertically so as to be on the right side, and the first soundboard 26a and the second soundboard 26b are in the same plane. 56 is fixed.

  Further, the control device 30 is configured in the same manner as in the first embodiment, and the phase control unit 20 constituting the control device 30 controls the phase of the input musical sound signal to thereby control the musical sound input to the actuator 24. Control is performed so that the phase difference of the signal is always constant. In this embodiment, as shown in FIG. 8, if the phase shift amount of the first phase control unit 20a is α and the phase shift amount of the second phase control unit 20b is β, β = α is set. The first phase control unit 20a and the second phase control unit 20b control the phase of the tone signal so that the phase difference of the tone signal is always 0 degrees, and the first actuator 24a and the second actuator 24b, respectively. Output to. For this reason, musical tone signals having the same phase are always input to the first actuator 24 a and the second actuator 24 b, and vibrations having the same phase are transmitted from the actuators 24 to the soundboards 26.

  In the electronic piano of the present embodiment configured as described above, the two soundboards 26 that face in the same direction and are arranged in the same plane vibrate in the same phase. Rather than simply oscillating a single soundboard, they can resonate with each other and produce a more expansive sound.

Since each soundboard 26 is arranged vertically, it is possible to simulate the resonance state of an upright piano in which the soundboard is arranged vertically, and the bass part is played on the left side of the keyboard and the treble part is played on the right side. .
As mentioned above, although the Example of this invention was described, it cannot be overemphasized that this invention can take a various form.

  In the present embodiment, the soundboards 26 of the two sound generators 22 face in the same direction (the angle formed by the sound planes of the soundboard 26 is 0 degrees) or face each other (the angle formed by the sound planes 26). 180 degrees), and examples of upright piano type and grand piano type electronic pianos have been described separately. However, a mechanism for rotating the sound generating unit 22 is provided inside the case of the electronic piano, and each angle The phase shift amount of the phase control unit 20 may be switched according to the above. In this way, both the upright piano and the grand piano can be obtained with one electronic piano.

  Furthermore, the angle formed between the plate surfaces of the soundboard 26 can be freely changed to other than 0 degrees and 180 degrees, and the phase shift amount of the phase control unit 20 is set to the angle formed between the plate surfaces of the soundboard 26. You may comprise so that it may switch more finely according to it. In addition, by using at least one of the phase control units 20 as a variable phase shifter, the phase of the musical sound signal output to the actuator 24 may be controlled more finely by the user.

  In the present embodiment, the musical tone signals input to the first sound generating unit 22a and the second sound generating unit 22b are the same signal. For example, a low tone musical signal has a large amplitude musical signal to the first sound generating unit 22a. And a musical sound signal with a small amplitude may be input to the second sound generator 22b. In this way, the bass generated by the low frequency signal is effectively emitted mainly from the first sound generator 22a by vibrating the first soundboard 26a larger than the second soundboard 26b. A resonance state close to the sound of a musical instrument can be obtained. And since the 1st actuator 24a which vibrates the 1st sound board 26a is located in the lower left vicinity of an electronic piano, ie, near the keyboard which plays a low tone, it can give a player the feeling close | similar to an acoustic musical instrument.

  In the present embodiment, the first sound generating unit 22a and the second sound generating unit 22b are each fixed to the case of the electronic piano, but the box of the first sound generating unit 22a and the second sound generating unit 22b. 28 may be coupled together. By doing so, propagation of vibration becomes complicated, and a more complicated resonance state can be generated.

  In this embodiment, the sound generator 22 is mounted inside the case of the electronic piano. However, the sound generator 22 can be freely arranged by configuring the sound generator 22 as a single unit, and a variable phase shifter can be used as the phase controller 20. By using it, the user may be able to freely control the phase. In this way, it is possible to input a musical tone signal of an instrument other than a piano such as a guitar to the phase control unit 20, and the phase control unit 20 can change the phase of the musical tone signal every time the sound generation unit 22 is replaced. Therefore, sound can be generated according to the user's preference.

  In this embodiment, the phase control unit 20 is provided next to the amplification unit 18 to control the phase of the analog signal. However, the phase control unit 20 is connected in front of the D / A conversion unit 16 to connect the digital signal. May be controlled.

It is a perspective view which shows the grand piano type electronic piano of 1st Example. It is a front view which shows the grand piano type electronic piano of 1st Example. It is a block diagram which shows the structure of a sound generation part. It is a block diagram which shows the structure of the control apparatus of an electronic piano. It is explanatory drawing which shows the phase control of the tone signal by the phase control part of 1st Example. It is a perspective view which shows the upright piano type electronic piano of 2nd Example. It is the front view and side view which show the upright piano type electronic piano of 2nd Example. It is explanatory drawing which shows the phase control of the musical tone signal by the phase control part of 2nd Example.

Explanation of symbols

2 ... Bus, 4 ... CPU, 6 ... RAM, 8 ... ROM, 10 ... DSP, 12 ... Keyboard, 14 ... Sound source, 16 ... D / A converter, 18 ... Amplifier, 20 ... Phase controller, 20a ... No. 1 phase control unit, 20b ... 2nd phase control unit, 22 ... sound generation unit, 22a ... 1st sound generation unit, 22b ... 2nd sound generation unit, 24 ... actuator, 24a ... 1st actuator, 24b ... 2nd actuator 26 ... sound board, 26a ... first sound board, 26b ... second sound board, 28 ... box, 30 ... control device, 40 ... electronic piano, 42 ... roof, 44 ... shelf board, 46 ... case, 50 ... electronic Piano, 52 ... Upper front plate, 54 ... Lower front plate, 56 ... Case

Claims (8)

A plurality of diaphragms each having at least one actuator attached to one side are driven, and the actuators are driven by a musical sound signal input from the outside to vibrate the diaphragms to simulate the resonance sound of an acoustic instrument. An acoustic system to generate,
A phase controller for controlling the phase of the tone signal input to the actuator of the prior SL each diaphragm,
As the plurality of diaphragms, comprising two diaphragms arranged so that the mounting surface of the actuator faces the same direction,
The phase control unit controls the phase of a musical sound signal input to each actuator so that the musical sound signals input to the actuators of the diaphragms are in phase with each other .   A plurality of diaphragms each having at least one actuator attached to one side are driven, and the actuators are driven by a musical sound signal input from the outside to vibrate the diaphragms to simulate the resonance sound of an acoustic instrument. An acoustic system to generate,
  A phase control unit for controlling the phase of a musical sound signal input to the actuator of each diaphragm;
  As the plurality of diaphragms, comprising two diaphragms arranged in parallel so that the mounting surfaces of the actuator face each other,
  The phase control unit controls the phase of the tone signal input to each actuator so that the tone signal input to the actuator of each diaphragm is in reverse phase.
  An acoustic system characterized by   The acoustic system according to claim 1, wherein the diaphragm forms one surface of a housing.   The acoustic system according to any one of claims 1 to 3, wherein the two diaphragms have different areas.   The acoustic system according to claim 1, wherein the diaphragm is made of a wooden soundboard.   The acoustic system according to claim 1, wherein the diaphragm is disposed inside an electronic musical instrument.   The acoustic system generates a resonance sound of a piano in a pseudo manner based on a musical sound signal of an electronic piano.
  The diaphragm is a wooden soundboard and is placed inside the electronic piano.
  The actuator is attached to one end side of the diaphragm,
  The first diaphragm, which is one of the two diaphragms, is arranged vertically on the back side of the lower front plate of the electronic piano so that the mounting surface of the actuator faces the inside of the electronic piano and the actuator is on the left side. ,
  The second diaphragm, which is another diaphragm, is disposed on the back side of the upper front plate so that the actuator is on the right side, and has an area smaller than that of the first diaphragm. The acoustic system according to 1.   The acoustic system generates a resonance sound of a piano in a pseudo manner based on a musical sound signal of an electronic piano.
  The diaphragm is a wooden soundboard and disposed inside the electronic piano,
  The actuator is attached to one end side of the diaphragm,
  The first diaphragm, which is one of the two diaphragms, is an upper part of the shelf of the electronic piano so that the actuator mounting surface of the first diaphragm faces the inside of the electronic piano and the actuator is on the left side. Placed horizontally on
  The other one of the second diaphragms is disposed in a lower part of the roof so that the actuator is on the right side, and has an area smaller than that of the first diaphragm. Acoustic system.