JP3543158B2 - Automatic accompaniment device - Google Patents

Description

[0001]
[Industrial applications]
The present invention relates to an automatic accompaniment apparatus that can easily play chords without being aware of fractional chords and non-fractional chords.
[0002]
[Prior art]
As is well known, in recent electronic musical instruments, the root (root note) and chord type (chord type) of a played chord (chord) are detected in order to assist chord and bass performances. An automatic accompaniment device is provided for automatically producing a chord sound and a base sound at a predetermined timing based on the result. Among devices of this type, a device that detects a fraction code and performs automatic accompaniment based on the detected fraction code is known. The fraction code isNormalChord sound and bass soundFromThis is a chord that is represented by an on-base chord.
[0003]
[Problems to be solved by the invention]
A so-called separation detection method is known as a mode for detecting a fractional code from a played chord. This separation detection method is such that when the pitch difference between the lowest note in the keypress pattern representing a key that has been pressed and the second bass is more than a certain distance apart, the lowest note is used as the base sound, This is a method of detecting the type from a key press pattern.
By the way, in a conventional automatic accompaniment device that detects a fraction code based on a separation detection method, the lowest note in a key press pattern is always regarded as a bass sound. When the seventh tone becomes the lowest note in the inverted form, it is always regarded as a fractional code, such as being regarded as a fractional code called "Measure on Flat Seventh". For this reason, in order to perform the inverted chord, the player must play a substitute chord or a basic chord that is not inverted, which results in a problem that it is difficult to perform.
[0004]
The present invention has been made in view of the above circumstances, and has as its object to provide an automatic accompaniment apparatus that can easily play chords without being conscious of fractional codes and non-fractional chords.
[0005]
[Means for Solving the Problems]
In order to achieve the above object, according to the first aspect of the present invention, the lowest pitch of a plurality of pitches designated by a performance operation performed in a pitch designation area divided into a first and a second tone range. Pitch extracting means for extracting the lowest pitch of the high pitch, the second low pitch next to the lowest pitch, and the third low pitch next to the second low pitch, and the lowest pitch extracted by the pitch extracting meansWhen the pitch name of the second pitch and the pitch name of the third pitch are arranged in the ascending direction based on the first pitch, the first pitch is defined as the first pitch. When one note name close to the name is the second note name and the other is the third note nameA first pitch difference indicating a pitch difference between the second pitch name and the third pitch name, and a first pitch difference indicating a pitch difference between the first pitch name and the second pitch name. A pitch difference generating means for generating a pitch difference between the first pitch and the second pitch;Pitch difference and theSecond pitch differenceAnd the lowest noteGenerates a chord type and a root note of a fractional chord in accordance with the above formula. On the other hand, when the lowest note is included in the second range, the first chord is generated.Pitch difference and theSecond pitch differenceAnd the lowest noteA chord type for generating a chord type and a root note of a non-fractional chord according to the chord, and an accompaniment sound generation instructing means for instructing generation of an accompaniment sound in accordance with the chord type and the root note generated by the chord determination means. It is characterized by doing.
[0006]
According to the second aspect of the present invention, of the plurality of pitches designated according to the performance operation, the lowest pitch of the lowest pitch, the second lowest pitch next to the lowest pitch, and the second pitch Pitch extracting means for extracting a third bass which is the second lowest, and a lowest tone extracted by the pitch extracting means.When the pitch name of the second pitch and the pitch name of the third pitch are arranged in the ascending direction based on the first pitch, the first pitch is defined as the first pitch. When one pitch name close to the name is the second pitch name and the other is the third pitch name,A first pitch difference representing a pitch difference between the second pitch name and the third pitch name, and a second pitch difference representing a pitch difference between the first pitch name and the second pitch name. A pitch difference generating means for generating a pitch difference between the first pitch difference and the first pitch difference when the second pitch difference is equal to or less than a predetermined frequency.Pitch difference and theSecond pitch differenceAnd the lowest noteIn response to theNonA chord type and a root note of a fractional chord are generated. On the other hand, when the second pitch difference is equal to or greater than a predetermined frequency, the first pitch difference is generated.Pitch difference and theSecond pitch differenceAnd the lowest noteAccording toMinuteA code discriminating means for generating a chord type and a root note of several codes, and an accompaniment sound generation instructing means for instructing generation of an accompaniment sound according to the chord type and the root note generated by the chord discriminating means. And
[0007]
According to the third aspect of the present invention, the code discriminating means includes a plurality of fractional codes corresponding to the first and second pitch differences in advance. A first discrimination table in which types are registered, and a second discrimination table in which a plurality of non-fractional code types and route change values are registered in advance corresponding to the first and second pitch differences. It is characterized.
Further, in the invention according to claim 3, which is dependent on claim 2, the code discriminating means regards the second pitch difference as a non-fractional code when the second pitch difference is less than or equal to a perfect fourth degree, and When the height difference is completely 5 degrees or more, it is regarded as a fraction code.
[0008]
[Action]
In the present invention, the pitch extracting means determines the lowest one of the lowest pitches among a plurality of pitches specified by the performance operation performed in the pitch specification area divided into the first and second pitches. A second lowest tone next to the lowest tone and a third lowest tone next to the second low tone are extracted, and the pitch difference generating means uses the lowest tone, the second low tone, and the third low tone as tone names, respectively. Converting, the first pitch of the lowest pitch, the second pitch next to the first pitch, and the third pitch next to the second pitch And a first pitch difference representing a pitch difference between the second pitch name and the third pitch name, and a pitch between the first pitch name and the second pitch name. And a second pitch difference representing the difference. Then, when the lowest note is included in the first range, the chord determining means generates a chord type and a root note of a fractional code according to the first and second pitch differences. When included in the second range, a chord type and a root note of a non-fractional chord are generated in accordance with the first and second pitch differences, and the accompaniment sound generation instructing means is generated by the chord discriminating means. Of the accompaniment sound according to the chord type and the root note to be played.
As a result, it is possible to easily play chords without being aware of fractional chords and non-fractional chords.
[0009]
【Example】
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
A. Configuration of the first embodiment
FIG. 1 is an external view showing an external appearance of an electronic musical instrument provided with an automatic accompaniment device according to a first embodiment of the present invention. The electronic musical instrument shown in FIG. 1 has a musical instrument body 1 and a keyboard 2 integrated with each other. In the keyboard 2, the key range is divided into a fraction code discrimination key area 2A and a non-fraction code discrimination key area 2B. Have been. In this embodiment, the pitch name C is used as the fraction code discrimination key area 2A.₁~ B_TwoIs assigned, and as the non-fractional code discrimination key area 2B, the pitch name C_ThreeA higher range is assigned, and the intention of such key range division will be described later. The musical instrument main body 2 has a panel switch 3 disposed on a console, and speakers SP on both sides of the console.
[0010]
Next, the configuration of the present embodiment will be described with reference to FIG. In this figure, the same elements as those shown in FIG. 1 are denoted by the same reference numerals. In FIG. 2, the keyboard 2 detects a key press / release key operation and a key press / release speed for each key, and outputs performance information such as a key-on signal, a key number, a key-off signal, or a velocity representing a touch / release touch. Among the panel switches 3 arranged on the console, for example, a tone switch for designating a tone, a pattern selection switch for selecting an accompaniment pattern, a mode switch 3a shown in FIG. There is a start / stop switch 3b for giving an instruction to stop. The mode switch 3a is a switch for selecting an operation mode of the electronic musical instrument. The mode switch 3a sets the drive power supply to an off state, an "OFF mode" for generating a musical tone in accordance with a normal performance operation, and a "normal mode". Select one of the "accompaniment modes" for automatic accompaniment. The start / stop switch 3b is a switch that alternately changes a start instruction / stop instruction according to a pressing operation.
[0011]
Reference numeral 4 denotes a CPU for controlling each section of the musical instrument, the operation of which will be described later. Reference numeral 5 denotes a ROM that stores various control programs loaded into the CPU 4 and various data used in these programs. Reference numeral 6 denotes a RAM used as a work area of the CPU 4, and temporarily stores various register / flag data. Reference numeral 7 denotes a tempo clock generation circuit for generating a tempo clock for designating a performance tempo during automatic accompaniment and supplying the generated tempo clock to the CPU 4. The term "automatic accompaniment" used herein means that when a player successively designates chords (chords) in accordance with the progress of the performance, the chord sound and the base sound that constitute the accompaniment pattern based on the designated chord are synchronized with the tempo clock. Refers to actions that accompany you automatically.
[0012]
Reference numeral 8 denotes a code discrimination table memory, which stores a discrimination table for discriminating a code type (or a code change value) based on a plurality of pressed keys, the details of which will be described later. Reference numeral 9 denotes an accompaniment pattern memory, which stores, for each rhythm type, accompaniment pattern data for a predetermined measure for controlling the sounding timing of the chord sound and the bass sound in accordance with the above-mentioned tempo clock. The accompaniment pattern data is selected according to the operation of a rhythm selection switch (not shown), and the selected patterns are sequentially read from the accompaniment pattern memory 9.
[0013]
Reference numeral 10 denotes a sound source configured by a well-known waveform memory reading method, which includes an accompaniment sound source in addition to a normal sound source that generates a tone according to a normal melody performance. The accompaniment sound source converts accompaniment sounds obtained by performing pitch conversion on accompaniment pattern data sequentially read from the accompaniment pattern memory 9 in synchronization with the tempo clock in accordance with a chord type CT and a root RT generated by chord discrimination processing described later. Generate. Reference numeral 11 denotes a sound system which performs D / A conversion of a tone signal output from the sound source 10, amplifies the signal, and causes the speaker SP to generate a tone as a tone.
[0014]
B. Configuration of code discrimination table memory 8
The chord discrimination table memory 8 stores information for discriminating a chord based on a key depression pattern representing a plurality of depressed keys. In this key depression pattern, the lowest note exists in the fraction code discrimination key area 2A described above. In this case, the code type of the fraction code is determined using the fraction code determination table CT1 shown in FIG. On the other hand, when the lowest note in the key pressing pattern exists in the above-described non-fractional code determination key area 2B, the root change value RH and the chord type CT are determined based on the non-fractional code determination table CT2 shown in FIG. You. These tables CT1 and CT2 are read out according to pitch differences CG1 and CG2 obtained by operations described later. The pitch differences CG1 and CG2 are values given by the following equations (1) and (2).
CG1 = | (KC2-KC1)% 12− (KC3-KC1)% 12 | (1)
CG2 = min {(KC2-KC1)% 12, (KC3-KC1)% 12} (2)
[0015]
In the above formulas (1) and (2), KC1, KC2 and KC3 are the lowest tone in the key pressing pattern when at least three or more keys are pressed, the second lowest tone, and the second lowest tone, respectively. It refers to the low third bass, and its value is given by MIDI note number. In the above equations (1) and (2), “% 12” is an operator representing modulo 12 (remainder value of 12), and min {A, B} is a solution of the smaller value of A and B. Operator.
Therefore, in the above equations (1) and (2), the lowest tone KC1, the second low tone KC2, and the third low tone KC3 in the key press pattern are respectively converted into 12 octaves (C, C #, D,. A #, B) is converted to the pitch name in the first pitch name of the lowest pitch name(KC1 note name is fixed)And a second note name that is lower than the first note name(KC2 or KC3 note name)And a third note name that is next to the second note name(KC3 or KC2 note name), A pitch difference CG1 representing a pitch difference between the second pitch name and the third pitch name, and a pitch difference CG representing a pitch difference between the first pitch name and the second pitch name.2Is calculated.
[0016]
C. Operation of the first embodiment
Next, the operation of the first embodiment having the above configuration will be described with reference to FIGS. Here, the operation of the main routine will be described as a schematic operation, and then the operations of various processing routines called in the main routine will be sequentially described.
(1) Main routine operation
First, when power is turned on to the electronic musical instrument according to the present embodiment, the CPU 4 loads a predetermined control program from the ROM 5, executes a main routine shown in FIG. 6, and proceeds to step SA2. In step SA2, various registers and flags provided in the RAM 6 are reset, and the sound source 10 is instructed to clear the tone generation channel register to zero. The tone channel register is a register provided inside the sound source 10 and temporarily stores tone parameters assigned to each tone channel under the instruction of the CPU 4.
[0017]
When the initialization for initializing the various registers is completed, the CPU 4 advances the processing to the next step SA4, and performs the switch processing according to the operation of the various panel switches 3 arranged on the console, for example, the mode switch 3a and the above-described mode switch 3a. Then, setting is performed in accordance with the operation of the start / stop switch 3b for instructing start / stop of the automatic accompaniment, and subsequently, in step SA6, in the case of the normal mode, a tone is generated in accordance with the performance operation. In the automatic accompaniment mode, based on an operation to be described later, a chord is discriminated based on a key depression pattern corresponding to a plurality of depressed keys, and keyboard processing for instructing generation of an accompaniment tone is performed according to the determined chord route and type. Then, the process proceeds to step SA8. For example, a switch scan for detecting the operation of various panel switches 3 provided on the console, and a liquid crystal display according to the switch setting status detected by the switch scan. Other processing such as panel display is performed. Next, the CPU 4 returns the process to step SA4, and thereafter repeats steps SA4 to SA8 to instruct the sound source 10 to generate a musical tone in accordance with the contents of the key press / release operation or the switch operation.
[0018]
(2) Operation of switch processing routine
Now, for example, when the player operates the panel switch 3, the CPU 4 executes the switch processing routine shown in FIG. 7 through the above-described step SA4, and proceeds to step SB2. In step SB2, it is determined whether or not the mode switch 3a has been operated. Here, if the setting operation is performed in the “normal mode”, the process proceeds to step SB8 described later, while if the operation is performed in the “automatic accompaniment mode”, the process proceeds to the next step SB4. At Step SB4, it is determined whether or not the start / stop switch 3b has been operated.
Here, when the switch 3b is not operated, the process proceeds to step SB8 to be described later, while when the switch 3b is operated, the process proceeds to the next step SB6, and the automatic accompaniment flag indicating start / stop of the automatic accompaniment is inverted. When this flag is "1", it indicates the start of automatic accompaniment, and when it is "0", it indicates that it is stopped. Then, after that, the CPU 4 makes settings in accordance with other switch operations, then ends this routine and returns to the above-described main routine.
[0019]
(3) Keyboard processing routine operation
After completing the switch processing routine and returning to the main routine, the CPU 4 executes the keyboard processing routine shown in FIG. 8 via the above-described step SA6, and proceeds to step SC2. In step SC2, it is determined whether or not the automatic accompaniment flag is “1”, that is, whether or not the automatic accompaniment is in a start state. Here, when the mode switch 3a is set to the "normal mode", the determination result is "NO" and the process proceeds to step SC4, where the predetermined tone color is determined according to the performance information generated in response to the key press / release operation. A normal performance process for instructing generation of a musical tone is performed, and the process returns to the main routine.
[0020]
On the other hand, if the mode switch 3a is set to the "automatic accompaniment mode" and the automatic accompaniment flag is set to "1" in response to the operation of the start / stop switch 3b, the determination result is "YES". Then, the process proceeds to Step SC6, and the key state is identified based on the performance information generated in response to the key press / release operation. Here, if there is no key-on / key-off event, this routine is terminated assuming that there is no key change. On the other hand, when a key-on event occurs due to a key pressing operation and the key state changes from off to on, the CPU 4 advances the process to step SC8. In step SC8, it is determined whether or not a plurality of keys are pressed within a predetermined time, that is, whether or not a chord is played.
[0021]
If it is a chord performance, the result of this determination is “YES”, and the process proceeds to step SC10. In step SC10, a chord discrimination process (described later) for instructing an automatic accompaniment based on the discriminated chord type CT / root RT is performed based on a key depression pattern representing a plurality of depressed keys.
On the other hand, if it is not a chord performance, the result of the determination in step SC8 is "NO", and the flow advances to step SC4 to perform a normal performance process for instructing a musical tone generation corresponding to a depressed key.
[0022]
Next, when the key state is changed from on to off by the key release operation in step SC6 described above, the CPU 4 advances the process to step SC12. In step SC12, it is determined whether or not the released key is a chord designation sound. Here, if it is not a chord designation sound, it is regarded as a normal key release, and the determination result is "NO". The process proceeds to step SC4 to instruct the mute of the musical tone corresponding to the released key.
On the other hand, when the sound is the chord designation sound, the judgment result is "YES". In this case, the automatic accompaniment proceeds in synchronization with the tempo clock, so that this routine is completed without doing anything.
[0023]
(4) Operation of code discrimination processing routine
Next, a code determination processing routine according to the gist of the present invention will be described. As described above, in the keyboard processing routine (see FIG. 8), when a plurality of keys are pressed within a predetermined time, that is, when a chord is played, the CPU 4 executes the chord determination processing routine shown in FIG. To step SD2. In step SD2, the lowest tone KC1, the second tone KC2, and the third tone KC3 are selected from the keys depressed.
[0024]
In the next step SD4, the selected lowest pitch KC1, second low pitch KC2, and third low pitch KC3 are substituted into the above-described equations (1) and (2) to calculate pitch differences CG1, CG2. Next, at step SD6, the lowest note KC1 is set to the fractional code key area 2A, that is,₁Sound ~ B_TwoIt is determined whether or not the lowest note KC1 exists in the key range of the note.
Hereinafter, the operation when the lowest note KC1 exists in the fractional chord key area 2A and the operation when the lowest note KC1 exists in the non-fractional chord key area 2B will be described separately.
[0025]
<Operation when the lowest tone KC1 exists in the fractional chord key area 2A>
In this case, the result of the determination in step SD6 is “YES”, and the flow proceeds to step SD8. In step SD8, the fraction code discrimination table CT1 shown in FIG. 4 is read out based on the pitch differences CG1 and CG2 calculated in step SD4.
Here, for example, among the keys depressed in accordance with the chord performance, the lowest tone KC1, the second bass KC2, and the third bass KC3 are "E2 (40)", "G3 (55)" and If it is “C4 note (60)” (the value accompanying the note name is the MIDI key code value), the pitch difference CG1 becomes “5", The pitch difference CG2 is"3". When the fraction code discrimination table CT1 (see FIG. 4) is read based on these values, the code type “Ab / C” is read. The code type defined in the table CT is for the case where the root is “C”.
[0026]
When the code type CT is read from the fraction code discrimination table CT1 in this way, the CPU 4 proceeds to the next step SD10, finds a route RT based on the following equation (3), stores it in the register RT, and reads it from the fraction code discrimination table CT1. The stored code type CT is stored in the register CT.
RT = KC1% 12 (3)
Therefore, in the case of the above example, the lowest tone KC1 is “E_TwoSince the sound is the sound (40), when the modulo 12 of the sound is obtained, the root RT is "4" and the sound name is the E sound.
[0027]
Then, when proceeding to the next step SD12, the CPU 4 reads out the code type CT stored in the register CT and the route RT stored in the register RT, and sends it to the sound source 10 to instruct the sound source 10 to generate an accompaniment sound.
After all, in the case of this example, since the root is “E sound” and the chord type is “Ab / C”, the fraction code “C / E” is given to the sound source 10. Thereby, the tone generator 10 generates the accompaniment sound by converting the accompaniment pattern data sequentially read from the accompaniment pattern memory 9 according to the chord type CT and the root RT.
[0028]
<Operation when lowest tone KC1 exists in non-fractional chord key range 2B>
In this case, the result of the determination in step SD6 is "NO", and the flow proceeds to step SD14. In step SD14, based on the pitch differences CG1 and CG2 calculated in step SD4, the non-fractional code discrimination table CT shown in FIG.2Is read out from the table.
Here, for example, among the keys depressed in accordance with the chord performance, the lowest tone KC1, the second bass KC2, and the third bass KC3 are "E3 tone (52)", "G3 tone (55)" and If it is “C4 sound (60)”, the pitch difference CG1 becomes “5” and the pitch difference CG2 becomes “3” by the calculation in step SD4. When the non-fractional code discrimination table CT2 (see FIG. 5) is read based on these values, the code type CT is read as "major" and the root change value RH is read as "-4". Note that the code type defined in the table CT2 is also a case where the root is “C”.
[0029]
When the code type CT and the route change value RH are read from the non-fractional code determination table CT2 in this way, the CPU 4 proceeds to the next step SD16, finds the route RT based on the following equation (4), stores the route RT in the register RT, and stores the route RT in the register RT. The code type CT read from the fraction code determination table CT2 is stored in the register CT.
RT = KC1% 12 + RH (4)
Therefore, in the case of the above example, the lowest tone KC1 is “E_ThreeSince the root change value RH “−4” is added to the modulo 12 of the note (52) ”, the root RT becomes“ 0 ”and the note name is the C note. Then, the process proceeds to step SD12, where the CPU 4 reads out the chord type CT stored in the register CT and the route RT stored in the register RT, and sends it to the sound source 10 to instruct the sound source 10 to generate an accompaniment sound. Therefore, in the case of this example, the code C is given to the sound source 10.
[0030]
As described above, according to the above-described first embodiment, the keyboard 2 is divided into the fractional code key area 2A and the non-fractional code key area 2B in the key range. If the lowest note KC1 is in the fraction code key area 2A, the code is regarded as a fraction code and the chord type is determined by referring to the fraction code discrimination table CT1, and this is converted into a fraction code with the lowest note KC1 as the root. Therefore, it is possible to easily play chords without being aware of fractional chords and non-fractional chords.
[0031]
D. Second embodiment
Next, a second embodiment of the present invention will be described. In the second embodiment, the configuration is the same as that of the first embodiment, and only the code discrimination processing is different in the operation. That is, in the first embodiment, when the lowest note KC1 is in the fractional chord key area 2A among the keys depressed in accordance with the chord performance, the fractional chord is determined, and the lowest note KC1 is determined in the non-fractional chord key area 2B. , The non-fractional chord is determined. However, in the chord determination processing routine according to the second embodiment, the lowest tone KC1 and the second low tone KC2 among the keys depressed in accordance with the chord performance are selected. Is determined, and whether the code is a fractional code or a non-fractional code is determined according to the determined pitch difference.
Hereinafter, regarding the operation of the chord determination processing routine of the second embodiment, the pitch difference between the lowest pitch KC1 and the second low pitch KC2 is “when the pitch is increased 4 degrees”, “when the pitch is not more than 4 degrees”, and “when the pitch is not more than 4 degrees”. The case will be described separately for the case of “5 degrees or more”.
[0032]
(1) When the pitch difference is 4 degrees
As in the first embodiment described above, when a plurality of keys are pressed within a predetermined time, that is, when a chord is played in the keyboard processing routine (see FIG. 8), the CPU 4 executes the chord determination processing shown in FIG. The routine is executed, and the process proceeds to step SE2. In step SE2, it is determined whether or not the pitch difference between the lowest tone KC1 and the second lower tone KC2, which is the next lower tone, is “increased fourth degree” among the keys depressed. In this case, since the case is “increased by 4 degrees”, the determination result is “YES” and the process proceeds to step SE4.
[0033]
If the pitch difference between the lowest pitch KC1 and the second low pitch KC2 is "increased 4th degree", the chord type is uniquely "7th (7th)". 5), the data is stored in the register RT, and the data corresponding to “Seventh (7th)” is set in the register CT.
RT = KC1% 12−4 ... (5)
Note that “KC1% 12” in the above equation (5) represents the modulo 12 of the MIDI key code value of the lowest tone KC1.
[0034]
Here, an example will be described. For example, among a plurality of keys pressed by a chord playing, the lowest note KC1 is "B_TwoSound (47) ”and the second bass KC2 are“ F_ThreeSound (53) ". Then, in this case, the pitch difference between the two sounds is “increased 4 degrees”, and in step SE4, the root RT is set to “7”, that is, “G sound” from equation (5), and the chord type CT is set to “ Seventh (7th) ". When the root and the chord type are determined in this way, the CPU 4 advances the processing to step SE6, reads out the chord type CT stored in the register CT and the root RT stored in the register RT, and sends out the accompaniment sound to the sound source 10. Instruct them to pronounce. Thereby, the tone generator 10 generates the accompaniment sound by converting the accompaniment pattern data sequentially read from the accompaniment pattern memory 9 according to the chord type CT and the root RT.
[0035]
(2) When the pitch difference is less than 4 degrees
In step SE2 described above, if the pitch difference is other than “increased fourth”, the determination result is “NO”, and the flow proceeds to step SE8. In step SE8, the lowest tone KC1, the second tone KC2, and the third tone KC3 are selected from the keys depressed. Next, when the process proceeds to step SE10, the CPU 4 substitutes the selected lowest tone KC1, second low tone KC2, and third low tone KC3 into the above-described equations (1) and (2) to calculate the pitch differences CG1, CG2. I do. Then, when the process proceeds to the next step SE12, it is determined whether the pitch difference between the lowest tone KC1 and the second low tone KC2 is "less than perfect fourth" or "more than perfect fifth".
[0036]
Here, when the pitch difference is “fourth degree or less”, the code becomes a non-fractional code, and the process proceeds to step SE14. In step SE14, the non-fractional code discrimination table CT2 shown in FIG. 5 is read out based on the pitch differences CG1 and CG2 calculated in step SE10.
Here, for example, among the keys depressed, the lowest tone KC1, the second bass KC2, and the third bass KC3 are each "E."_TwoSound (40) "," G_TwoAssuming that the sound is the sound (43) and the sound C3 (48), the pitch difference CG1 becomes “5” and the pitch difference CG2 becomes “3” by the calculation in step SE10. When the non-fractional code discrimination table CT2 (see FIG. 5) is read based on these values, the code type CT is read as "major" and the root change value RH is read as "-4".
[0037]
When the code type CT and the route change value RH are read from the non-fractional code discrimination table CT2 in this manner, the CPU 4 proceeds to the next step SE16, finds the route RT based on the above-described equation (4), stores it in the register RT, and The code type CT read from the non-fractional code determination table CT2 is stored in the register CT.
Therefore, in this example, the lowest note KC1 is “E_TwoSince the root change value RH “−4” is added to the modulo 12 of the sound (40), the root RT becomes “0” and the pitch name becomes the C sound. Then, the process proceeds to step SE6, in which the obtained chord type CT and root RT are transmitted to the sound source 10 to instruct the sound source 10 to generate an accompaniment sound.
[0038]
(3) When the pitch difference is more than 5 degrees
In this case, the code is a fraction code, and the flow advances to step SE18 via step SE12. In step SE18, the fraction code discrimination table CT1 shown in FIG. 4 is read out based on the pitch differences CG1 and CG2 calculated in step SE10.
Here, for example, among the keys depressed in accordance with the chord performance, the lowest tone KC1, the second bass KC2, and the third bass KC3 are each "E."_TwoSound (40) "," C_ThreeSound (48) ”and“ G_ThreeIf it is "sound (55)", the pitch difference CG1 is "5" and the pitch difference CG2 is "3". When the fraction code discrimination table CT1 (see FIG. 4) is read based on these values, the code type “Ab / C” is read.
[0039]
When the code type is read from the fraction code discrimination table CT1 in this way, the CPU 4 proceeds to the next step SE20, finds the root RT based on the above-mentioned equation (3), stores it in the register RT, and reads it from the fraction code discrimination table CT1. The stored code type is stored in the register CT.
Therefore, in the case of the above example, the lowest tone KC1 is “E_TwoSince the sound is the sound (40), when the modulo 12 of the sound is obtained, the root RT is "4" and the sound name is the E sound.
[0040]
Then, when proceeding to the next step SE6, the CPU 4 reads out the code type CT stored in the register CT and the route RT stored in the register RT, and sends it to the sound source 10 to instruct the sound source 10 to generate an accompaniment sound.
After all, in the case of this example, since the root is “E sound” and the chord type is “Ab / C”, the fraction code “C / E” is given to the sound source 10. Thereby, the tone generator 10 generates the accompaniment sound by converting the accompaniment pattern data sequentially read from the accompaniment pattern memory 9 according to the chord type CT and the root RT.
[0041]
As described above, according to the second embodiment, among the keys depressed according to the chord performance, whether the key is a fractional code or a non-fraction code according to the pitch difference between the lowest tone KC1 and the second bass KC2. It is discriminated whether the code is a fraction code, and if the code is a fraction code, the code is determined by referring to the fraction code discrimination table CT1. If the code is a non-fraction code, the code is discriminated by referring to the non-fraction code discrimination table CT2. It is possible to easily play a chord without being aware of a non-fractional chord.
In the first and second embodiments described above, the pitch differences CG1 and CG2 are both 5 semitones.DifferenceUses the tables CT1 and CT2, but is not limited to this, and may use six semitones.differenceThe above table may be defined.
[0042]
【The invention's effect】
According to the present invention, the pitch extracting means selects the lowest pitch of the lowest pitch among a plurality of pitches specified by the performance operation performed in the pitch specification area divided into the first and second pitches. Extracting the second lowest tone next to the lowest tone and the third lowest tone next to the second low tone, and generating the pitch difference by the lowest pitch, the second low tone, and the third low tone.ofEach note nameIn a predetermined order, The first pitch of the lowest pitch, the second pitch next to the first pitch, and the third pitch next to the second pitch. On the other hand, a first pitch difference representing a pitch difference between the second pitch name and the third pitch name, and a pitch difference between the first pitch name and the second pitch name are calculated. And a second pitch difference representing the second pitch difference. Then, when the lowest note is included in the first range,SaidFirst and second pitch differenceAnd the lowest soundThe chord type and the root note of the fractional chord are generated according to the following formula. On the other hand, when the lowest note is included in the second range,SaidFirst and second pitch differenceAnd the lowest soundThe chord type and root tone of the non-fractional chord are generated according to, and the accompaniment sound generation instructing means instructs the generation of the accompaniment tone according to the chord type and root chord generated by the chord discriminating means. A chord can be easily played without being aware of non-fractional chords.
[Brief description of the drawings]
FIG. 1 is an external view showing an external appearance of an electronic musical instrument according to a first embodiment of the present invention.
FIG. 2 is a block diagram illustrating a configuration of a first embodiment.
FIG. 3 is a diagram for explaining a panel switch 3 in the embodiment.
FIG. 4 is a diagram showing contents of a fraction code discrimination table CT1 in the embodiment.
FIG. 5 is a diagram showing contents of a non-fractional code discrimination table CT2 in the embodiment.
FIG. 6 is a flowchart for explaining the operation of a main routine in the embodiment.
FIG. 7 is a flowchart for explaining the operation of a switch processing routine in the embodiment.
FIG. 8 is a flowchart for explaining the operation of a keyboard processing routine in the embodiment.
FIG. 9 is a flowchart for explaining the operation of a code determination processing routine in the embodiment.
FIG. 10 is a flowchart for explaining the operation of a code determination processing routine according to the second embodiment.
[Explanation of symbols]
2 keys
2A Fractional code discrimination key range (first range)
2B Non-fractional chord discrimination key range (second range)
4 CPU (pitch extraction means, pitch difference generation means, code discrimination means)
5 ROM
6 RAM
8. Code discrimination table memory (code discrimination means)

Claims (4)

Among the plurality of pitches specified by the performance operation performed in the pitch specification area divided into the first and second pitches, the lowest pitch of the lowest pitch and the second low pitch next to the lowest pitch And a pitch extracting means for extracting a third bass which is next to the second bass,
The pitch name of the lowest tone extracted by the pitch extracting means is defined as a first pitch name, and the pitch name of the second low pitch and the third low pitch is determined in an ascending direction with the first pitch as a base point. When arranged, one pitch name close to the first pitch name is set as a second pitch name, and the other is set as a third pitch name , the second pitch name and the third pitch name. Means for generating a first pitch difference representing a pitch difference between the first pitch name and a second pitch difference representing a pitch difference between the first pitch name and the second pitch name. When,
When the lowest note is included in the first range, a chord type and a root note of a fractional code are generated according to the first pitch difference, the second pitch difference, and the lowest note. On the other hand, if the lowest note is included in the second range, the code type of the non-fractional code is determined according to the first pitch difference, the second pitch difference, and the lowest note. And chord determining means for generating a root sound
An automatic accompaniment apparatus comprising: an accompaniment sound generation instructing means for instructing generation of an accompaniment sound in accordance with a chord type and a root sound generated by the chord identification means. Among the plurality of pitches designated according to the performance operation, the lowest pitch of the lowest pitch, the second low pitch next to the lowest pitch, and the third low pitch next to the second low pitch Pitch extracting means for extracting,
The pitch name of the lowest tone extracted by the pitch extracting means is defined as a first pitch name, and the pitch name of the second low pitch and the third low pitch is determined in an ascending direction with the first pitch as a base point. When arranged, one pitch name close to the first pitch name is set as a second pitch name, and the other is set as a third pitch name, the second pitch name and the third pitch name. Means for generating a first pitch difference representing a pitch difference between the first pitch name and a second pitch difference representing a pitch difference between the first pitch name and the second pitch name. When,
When the second pitch difference is equal to or less than a predetermined frequency, a chord type and a root note of a non- fractional code are changed according to the first pitch difference, the second pitch difference, and the lowest note. produced, whereas, wherein when the second pitch difference is equal to or more than a predetermined degree, the code of the partial number of codes in response to said first pitch difference between said second pitch difference between the lowest tone Chord discriminating means for generating a type and a root note;
An automatic accompaniment apparatus comprising: an accompaniment sound generation instructing means for instructing generation of an accompaniment sound in accordance with a chord type and a root sound generated by the chord identification means. Said code determination means, a first determination table in which a plurality of fraction code type is registered in correspondence to advance the first pitch difference and the second pitch difference,
A second determination table in which a plurality of non fraction code type and route change value is registered in correspondence to advance the first pitch difference and the second pitch difference,
The automatic accompaniment device according to claim 1, further comprising: The code discriminating means regards the second pitch difference as a non-fractional code when the second pitch difference is equal to or less than a perfect fourth, and regards the code as a fraction code when the second pitch difference is a perfect fifth or more. 3. The automatic accompaniment device according to claim 2, wherein

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