The present invention relates to a technology for generating a sound signal in an electronic musical instrument.
Various devices have been designed to make sounds from electronic pianos as close as possible to sounds of acoustic pianos. An example is Patent Literature 1 (Japanese Laid-Open Patent Publication 2014-59534), in which when a key is depressed in playing an acoustic piano, not only is a string striking sound produced, but also a keybed hitting sound is produced along with the depression of the key. In the field of electronic musical instruments such as electronic pianos, technologies for reproducing such keybed hitting sounds have been disclosed.
According to an embodiment of the present invention, there is provided an electronic musical instrument including a sound source configured to generate a first sound signal and a second sound signal in accordance with an instruction signal for instructing to produce a sound, a first output unit configured to output a third sound signal containing the first sound signal and the second sound signal at a first sound volume ratio, and a second output unit configured to output a fourth sound signal containing the first sound signal and the second sound signal at a second sound volume ratio that is different from the first sound volume ratio.
According to an embodiment of the present invention, there is provided an electronic musical instrument including a sound source configured to generate a first sound signal and a second sound signal in accordance with an instruction signal for instructing to produce a sound, a first output unit configured to output a third sound signal containing the first sound signal and not containing the second sound signal, and a second output unit configured to output a fourth sound signal containing the first sound signal and the second sound signal.
In the following, an electronic keyboard musical instrument according to an embodiment of the present invention is described in detail with reference to the drawings. Embodiments to be described below are examples of embodiments of the present invention, and the present invention is not construed within the limitations of these embodiments. It should be noted that in the drawings that are referred to in the present embodiment, identical parts or parts having the same functions are given identical signs or similar signs (signs each formed simply by adding A, B, or the like to the end of a number) and a repeated description thereof may be omitted.
Most electronic pianos include speakers for outputting sounds of pianos. The generation of a sound of a piano by the technology disclosed in Patent Literature 1 causes a sound that is outputted from a speaker to contain a keybed hitting sound. Meanwhile, for the realization of a sense of playing which is close to the sense of playing an acoustic piano, a structure which is similar to that of an acoustic piano is sometimes employed as the mechanical structure of parts (key assembly) surrounding keys in an electronic piano. In such a case, there is no need to aggressively employ the technology disclosed in Patent Literature 1, as an actual keybed hitting sound produced is heard by the player, as is the case with an acoustic piano.
In addition to a speaker, an electronic piano includes an output terminal though which a sound signal is outputted to an external device such as a headphone so that the external device produces a sound. Meanwhile, in a case where the player uses the headphone, it becomes hard for the player to hear an actual keybed hitting sound. Accordingly, as compared with a case where the player hears a sound from the speaker, the player has had to hear a sound without a sense of a keybed hitting sound.
Meanwhile, thought is given to a case where the technology disclosed in Patent Literature 1 is employed so that the player can hear a keybed hitting sound even when the player uses the headphone. In this case, using the speaker causes a keybed hitting sound mechanically produced and a keybed hitting sound from the speaker to be heard as an overlapped sound. In either case, the player has had to hear different sounds, depending on the difference between devices that output sounds. Accordingly, the player has had to sense such unnaturalness that sounds vary from hearing environment to hearing environment even when the player does the same performance.
The present invention makes it possible to provide a technology that makes it possible to, despite the difference between devices that output sounds, make sounds to be heard differ as little as possible from each other. The following describes each component of the electronic keyboard musical instrument 1 in detail.
The electronic keyboard musical instrument 1 includes the plurality of key 70 (playing operators). The plurality of keys 70 are rotatably supported by a housing 50. The housing 50 is provided with the operating unit 21, a display unit 23, and the speaker 60 (first output unit). The housing 50 has disposed therein a control unit 10, a storage unit 30, a key behavior measuring unit 75, and a sound source 80. The components disposed in the housing 50 are connected to each other via a bus.
In this example, the electronic keyboard musical instrument 1 includes an interface though which signals are inputted and outputted to and from an external device. Examples of the interface include a terminal through which a sound signal is outputted to the external device, a cable connection terminal through which MIDI data is transmitted and received, and the like. In this example, an output terminal (second output unit) through which a sound signal is outputted includes a headphone terminal 91 to which a headphone is connected as the external device and a LINE terminal 95 through which line output is done.
The control unit 10 includes an arithmetic processing circuit such as a CPU and a storage device such as a RAM or a ROM. The control unit 10 executes, through the CPU, a control program stored in the storage unit 30 and thereby allows the electronic keyboard musical instrument 1 to achieve various types of functions. The operating unit 21 includes devices such as operation buttons, a touch sensor, sliders and outputs, to the control unit 10, a signal corresponding to an operation inputted. The display unit 23 displays a screen based on control exercised by the control unit 10.
The storage unit 30 is a storage device such as a nonvolatile memory. The storage unit 30 has stored therein the control program that is executed by the control unit 10. Further, the storage unit 30 may have stored therein parameters, waveform data, and the like that are used in the sound source 80. The speaker 60 amplifies and outputs a sound signal that is outputted from the control unit 10 or the sound source 80 and thereby produces a sound corresponding to the sound signal.
The key behavior measuring unit 75 measures the behavior of each of the plurality of keys 70 and outputs measurement data representing a measurement result. In this example, the measurement data contains information corresponding to a key 70 that has been depressed and an amount of depression (amount of operation) of the key 70. In this example, the key behavior measuring unit 75 is designed to, upon detecting first, second, and third amounts of depression of a key 70, output detection signals corresponding the amounts of depression. The key 70 that has been depressed can be identified by containing information (e.g. a key number) indicating the key 70.
A hammer connecting part 706 projecting toward a lower position than the key 70 includes a coupling part 707 at a lower end thereof. The key connecting part 761 and the coupling part 707, which are disposed at one end of the hammer 76, are slidably connected to each other. The hammer 76 includes a weight 768 (second member) on a side of the spindle 765 opposite to the key connecting part 761. When the key 70 is not being operated, the weight 768 is placed on a lower limit stopper 791 by its own weight.
Meanwhile, depression of the key 70 causes the key connecting part 761 to move downward, and rotation of the hammer 76 causes the weight 768 to move upward. A collision of the weight 768 with an upper limit stopper 792 (first member) restricts the rotation of the hammer 76, so that the key 70 becomes unable to be depressed. A strong depression of the key 70 causes the hammer 76 (weight 768) to hit the upper limit stopper 792, and a hitting sound is produced at that time. This hitting sound may be transmitted to the keybed 58 via the frame 78 and emitted as a louder sound. In the configuration of
It should be noted that the key assembly is not limited to the structure shown in
The key behavior measuring unit 75 (first sensor 75-1, second sensor 75-2, third sensor 75-3) is disposed between the frame 78 and the key 70. Depressing the key 70 causes the first sensor 75-1 to output a first detection signal when the key 70 has reached the first amount of depression. Then, the second sensor 75-2 outputs a second detection signal when the key 70 has reached the second amount of depression. Furthermore, the third sensor 75-3 outputs a third detection signal when the key 70 has reached the third amount of depression. A velocity of depression and acceleration of depression of the key 70 can be calculated from temporal differences in output timing among the detection signals.
In this example, the control unit 10 calculates a first velocity of depression on the basis of the time from the output timing of the first detection signal to the output timing of the second detection signal and predetermined distances (here, distances to the first amount of depression and the second amount of depression). Similarly, the control unit 10 calculates a second velocity of depression on the basis of the time from the output timing of the second detection signal to the output timing of the third detection signal and predetermined distances (here, distances to the second amount of depression and the third amount of depression). The control unit 10 calculates an acceleration of depression on the basis of the first velocity of depression and the second velocity of depression. Furthermore, the control unit 10 outputs a note-on Non to the sound source 80 upon detection of the third detection signal and, after having outputted the note-on Non and upon stoppage of the output of the first detection signal for the same key, outputs a note-off Noff to the sound source 80.
When a note-on Non is outputted, a key number Note, a velocity of depression Vel (the first velocity of depression or the second velocity of depression), and an acceleration of depression Acc are outputted in association with the note-on Non. The key number Note is information for identifying the key 70 that has been depressed, and corresponds to information (pitch information) that designates the pitch of a sound.
On the other hand, when a note-off Noff is outputted, the key number Note is outputted in association with the note-off Noff. It should be noted that in the following description, these pieces of information (operating information) which are outputted from the control unit 10 along with the operation of the key 70 are supplied to the sound source 80 as an instruction signal that gives an instruction to produce a sound.
The description goes on with continued reference to
The string striking sound signal output unit 81 outputs, in accordance with an instruction signal that is supplied in response to depression of a key 70, a sound signal (string striking sound signal: first sound signal) that is equivalent to a string striking sound of a piano. The string striking sound signal output unit 81 includes a string striking sound waveform memory 811, a string striking sound signal generating unit 813, a string striking sound volume table 815, and a string striking sound delay table 817.
The string striking sound waveform memory 811 has stored therein waveform data representing string striking sounds of a piano. This waveform data is waveform data obtained by sampling sounds of an acoustic piano (i.e. sounds produced by string striking entailed by key depression). In this example, waveform data of different pitches are stored in association with key numbers.
The string striking sound signal generating unit 813 reads out waveform data from the string striking sound waveform memory 811 in accordance with an instruction signal, subjects the waveform data to envelope processing, which is for example controlled by ADSR parameters, and outputs the waveform data as a string striking sound signal. The string striking sound signal is outputted to the speaker output synthesizing unit 83 and the terminal output synthesizing unit 84.
The string striking sound signal generating unit 813 determines, on the basis of the key number Note, the pitch of the waveform data to be read out. This causes the string striking sound signal generating unit 813 to generate a string striking sound signal having a pitch corresponding to the key number Note. That is, in a case where the key number Note has changed by a predetermined pitch difference, the pitch of the string striking sound signal changes according to this pitch difference. The string striking sound signal generating unit 813 determines the sound volume (maximum amplitude) of the string striking sound signal with reference to the string striking sound volume table 815. The string striking sound signal generating unit 813 determines a delay time from reception of an instruction signal representing a note-on Non to outputting of a string striking sound signal with reference to the string striking sound delay table 817. The timing of generation (timing of production) of the string striking sound signal changes according to this delay time. The string striking sound volume table 815 and the string striking sound delay table 817 will be described in detail later.
The hitting sound signal output unit 82 outputs, in accordance with an instruction signal that is supplied in response to depression of a key 70, a sound signal (hitting sound signal: second sound signal) that is equivalent to a keybed hitting sound. The hitting sound signal output unit 82 includes a hitting sound waveform memory 821, a hitting sound signal generating unit 823, a hitting sound volume table 825, and a hitting sound delay table 827.
The hitting sound waveform memory 821 has stored therein waveform data representing keybed hitting sounds of a piano. This waveform data is waveform data obtained by sampling keybed hitting sounds entailed by depression of keys of an acoustic piano. Unlike the string striking waveform memory 811, which has waveform data stored therein, the hitting sound waveform memory 821 does not have stored therein waveform data whose pitches vary according to key number. That is, the hitting sound waveform memory 821 has common waveform data stored therein regardless of key number.
The hitting sound signal generating unit 823 reads out waveform data from the hitting sound waveform memory 821 in accordance with an instruction signal and outputs the waveform data as a hitting sound signal. The hitting sound signal is outputted to the speaker output synthesizing unit 83 and the terminal output synthesizing unit 84. It should be noted that although, in this example, envelope processing is not performed on the hitting sound signal, it may be performed. In a case where envelope processing is not performed, the hitting sound waveform memory 821 has stored therein waveform data of a predetermined period of time. Upon reading out waveform data in accordance with an instruction signal for a predetermined period of time, the hitting sound signal generating unit 823 finishes generating a hitting sound signal corresponding to this instruction signal.
The hitting sound signal generating unit 823 determines the sound volume (maximum amplitude) of the hitting sound signal with reference to the hitting sound volume table 825. The hitting sound signal generating unit 823 determines a delay time from reception of an instruction signal representing a note-on Non to outputting of a hitting sound signal with reference to the hitting sound delay table 827. The timing of generation (timing of production) of the hitting sound signal changes according to this delay time. It should be noted that in this example, in which the hitting sound waveform memory 821 does not have stored therein waveform data of different pitches, the hitting sound signal generating unit 823 does not need to use the key number Note. That is, the pitch of the hitting sound signal does not change even when the key number Note changes by a predetermined pitch difference.
The following describes specific contents of each table (string striking sound volume table 815, hitting sound volume table 825, string striking sound delay table 817, hitting sound delay table 827).
When the acceleration of depression Acc is A2, the string striking sound delay time t1 and the hitting sound delay time t2 become equal to each other. When the acceleration of depression Acc is A1, which is smaller than A2, the hitting sound delay time t2 becomes a longer time than the string striking sound delay time t1. On the other hand, when the acceleration of depression Acc is A3, which is larger than A2, the hitting sound delay time t2 becomes a shorter time than the string striking sound delay time t1. A2 may be “0”. In this case, A1 takes on a negative value and indicates gradual deceleration during depression. On the other hand, A3 takes on a positive value and indicates gradual acceleration during depression.
It should be noted that although, in the example shown in
The foregoing has described each table. As mentioned above, the string striking sound signal generating unit 813 determines, on the basis of the key number Note, the pitch of the waveform data to be read out. On the other hand, in this example, the hitting sound signal generating unit 823 does not allow the pitch of the waveform data to be read out to change according to the key number Note.
The description goes on with continued reference to
The terminal output synthesizing unit 84 includes amplifying units 841 and 842 and a synthesizing unit 845. The amplifying unit 841 amplifies, by a predetermined amplification factor, a string striking sound signal outputted from the string striking sound signal generating unit 813. The amplifying unit 842 amplifies, by a predetermined amplification factor, a hitting sound signal outputted from the hitting sound signal generating unit 823. The synthesizing unit 845 combines by addition the string striking sound signal amplified by the amplifying unit 841 and the hitting sound signal amplified by the amplifying unit 842 and outputs them. These configurations cause the terminal output synthesizing unit 84 to output a terminal sound signal (fourth sound signal) made by combining the string striking sound signal and the hitting sound signal at a predetermined second sound volume ratio. It should be noted that in the following description, the first sound volume ratio and the second sound volume ratio both refer to the proportion of the maximum amplitude (which corresponds to the hitting sound volume Vb) of the hitting sound signal to the maximum amplitude (which corresponds to the string striking sound volume Va) of the string striking sound signal.
As shown in
The description goes on with continued reference to
It should be noted that a sound signal (terminal sound signal) that is outputted from the terminal output synthesizing unit 84 is also supplied to the LINE terminal 95. In this example, a path (hereinafter referred to as “LINE path”) of a sound signal from the terminal output synthesizing unit 84 to the LINE terminal 95 does not include a switch of the output switching unit 85. That is, the terminal sound signal to the LINE terminal is always supplied.
The amplified output unit 86 includes amplifying units 861, 862, and 863. The amplifying unit 861 is provided on the speaker path. The amplifying unit 862 is provided on the headphone path. The amplifying unit 863 is provided on the LINE path. The amplifying units 861, 862, and 863 are set at a predetermined amplification factor. The setting of this amplification factor can be changed by operating a volume knob or the like of the operating unit 21.
The aforementioned configuration causes the sound source 80 to output the speaker sound signal through the speaker 60 and outputs the terminal sound signal, which contains more components of a hitting sound signal than the speaker sound signal, through the headphone terminal 91 and the LINE terminal 95. A sound that is outputted from the speaker 60 is combined with a hitting sound that is mechanically produced from the key assembly, and is heard by the player. Therefore, even when the output from the speaker 60 contains few or no components of a hitting sound signal, the player can hear a keybed hitting sound.
On the other hand, in using the headphone terminal 91, the player hardly hears a mechanically-produced hitting sound. Since a sound that is outputted from the headphone terminal 91 contains many components of a hitting sound signal, the aforementioned sound source 80 enables the player to hear a hitting sound produced by the sound source 80 instead of a mechanical hitting sound.
In the first embodiment, in a case where a sound that is outputted from the speaker 60 does not contain a hitting sound signal, i.e. a case where the first sound volume ratio is 0, the amplification factor of the amplifying unit 842 is achieved by being set to 0. In a second embodiment, this is achieved by a different configuration.
Still another sound may be added to a sound that is outputted from the speaker 60 according to the first embodiment. In a third embodiment, an example is described in which a reverberation sound signal (fifth sound signal) that corresponds to reverberation at the time of transmission of a keybed hitting sound to the soundboard or the like of a grand piano is added.
As mentioned above, a sound that is outputted from the speaker 60 is combined with a hitting sound that is mechanically produced from the key assembly, and is heard by the player. The electronic keyboard musical instrument 1 does not include a large structure such as a soundboard in comparison with an acoustic piano. Therefore, a hitting sound that is mechanically produced in the electronic keyboard musical instrument 1 may contain fewer reverberation components than a hitting sound of an acoustic piano. In this example, a reverberation sound signal represents a sound that is equivalent to such a reverberation component. Accordingly, a reverberation component of a hitting sound of an acoustic piano can be reinforced by a sound (speaker sound signal) that is outputted from the speaker 60. Since a terminal sound signal contains extra components of a hitting sound signal, the hitting sound signal in itself may contain a reverberation component.
It should be noted that since a hitting sound signal contains a reverberation component, too, control may be exercised so that the larger amplification factor the amplifying unit 831 is set at, the smaller the sound volume of a reverberation sound signal that is outputted from the reverberation sound signal output unit 88 becomes. Further, in a case where the first sound volume ratio is 0, a configuration in which the amplifying unit 832 is not used may be set up, or the second embodiment may be provided with a synthesizing unit that combines a string striking sound signal and a reverberation sound signal by addition.
In the foregoing, embodiments of the present invention have been described. However, the embodiments may employ embodiments combined or replaced with each other. Further, the embodiments of the present invention may be modified into various forms as below. The modifications to be described below can also be applied in combination with each other.
(1) In each of the aforementioned embodiments, the sound volume ratio between a string striking sound signal and a hitting sound signal in a terminal sound signal that is supplied to the headphone terminal 91 and the sound volume ratio between a string striking sound signal and a hitting sound signal in a terminal sound signal that is supplied to the LINE terminal 95 are equal to each other. Alternatively, these sound volume ratios may be different from each other.
(2) In each of the aforementioned embodiments, the electronic keyboard musical instrument 1 has been described as an example of an electronic musical instrument. Alternatively, instead of being a keyboard musical instrument, the electronic musical instrument needs only be a musical instrument having a playing operator. That is, the electronic musical instrument may be configured to include a playing operator other than the keys 70. The sound source according to any of the aforementioned may be applied to an electronic musical instrument assuming the form of an acoustic musical instrument in which a hitting sound is produced by operating a playing operator. A possible example of a hitting sound that is produced in a woodwind instrument is a sound of a lid being opened and closed by a key operation. In a case where such a woodwind instrument takes the form of an electronic musical instrument, it is effective to have a structure in which a hitting sound is produced by an operation on a playing operator and then apply the sound source according to any of the aforementioned embodiments.
(3) In each of the aforementioned embodiments, the supply of a sound signal to either the speaker 60 or the headphone terminal 91 is achieved by switching paths by means of the output switching unit 85. Alternatively, this may be achieved by adjusting the amplification factors of the amplifying units 861 and 862 and restricting output to either of them.
(4) In each of the aforementioned embodiments, the hitting sound waveform memory 821 has common waveform data stored therein regardless of key number. Alternatively, as is the case with the waveform data stored in the string striking sound waveform memory 811, different pieces of waveform data may be stored with respect to a key number, and the same waveform data may be associated with at least two key numbers (namely a key number representing a first pitch and a key number representing a second pitch).
(5) In each of the aforementioned embodiments, the electronic keyboard musical instrument 1 includes the speaker 60. Alternatively, instead of including the speaker 60, the electronic keyboard musical instrument 1 may include a terminal through which a sound signal is supplied to the speaker. In this case, a speaker sound signal needs only be supplied to this terminal.
(6) In each of the aforementioned embodiments, a string striking sound signal and a hitting sound signal are generated at different timings. Alternatively, these signals may be generated at the same time.
(7) In each of the aforementioned embodiments, even a change in the key number Note by a predetermined pitch difference does not lead to a change in the pitch of a hitting sound signal. Alternatively, this pitch may change. In this case, the pitch of a hitting sound signal may change in a manner similar to the pitch of a string striking sound signal or may change by a smaller pitch difference than a string striking sound signal. Thus, in a case where the key number Note has changed by a predetermined pitch difference, the pitch of a string striking sound signal and the pitch of a hitting sound signal need only be different in magnitude of the change from each other.
(8) In each of the aforementioned embodiments, the sound source generates and combines a string striking sound signal and a hitting sound signal. Alternatively, such a combination does not impose any limitation, provided two types of sound signal are generated and combined.
1 . . . electronic keyboard musical instrument, 10 . . . control unit, 21 . . . operating unit, 23 . . . display unit, 30 . . . storage unit, 50 . . . housing, 58 . . . keybed, 60 . . . speaker, 75 . . . key behavior measuring unit, 75-1 . . . first sensor, 75-2 . . . second sensor, 75-3 . . . third sensor, 76 . . . hammer, 78 . . . frame, 80 . . . sound source, 81 . . . string striking sound signal output unit, 82 . . . hitting sound signal output unit, 83 . . . speaker output synthesizing unit, 84 . . . terminal output synthesizing unit, 85 . . . output switching unit, 86 . . . amplified output unit, 89 . . . connection detecting circuit, 91 . . . headphone terminal, 95 . . . LINE terminal, 706 . . . hammer connecting part, 707 . . . coupling part, 761 . . . key connecting part, 765 . . . spindle, 768 . . . weight, 781 . . . key supporting member, 782 . . . spindle, 785 . . . hammer supporting member, 791 . . . lower limit stopper, 792 . . . upper limit stopper, 811 . . . string striking sound waveform memory, 813 . . . string striking sound signal generating unit, 815 . . . string striking sound volume table, 817 . . . string striking sound delay table, 821 . . . hitting sound waveform memory, 823 . . . hitting sound signal generating unit, 825 . . . hitting sound volume table, 827 . . . hitting sound delay table, 831, 832 . . . amplifying unit, 841, 842 . . . amplifying unit, 851,852 . . . switch, 861, 862, 863 . . . amplifying unit
This application is a U.S. continuation application filed under 35 U.S.C. § 111(a), of International Application No. PCT/JP2017/036168, filed on Oct. 4, 2017, the disclosures of which are incorporated by reference.
Number | Date | Country | |
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Parent | PCT/JP2017/036168 | Oct 2017 | US |
Child | 16816811 | US |