JPH10171457A - Automatic accompaniment device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform automatic accompaniment without causing jumping in a consecutive accompaniment sound. SOLUTION: Twelve sound pitches of each semitone from C to B are made to correspond to numerical values of 0 to 11 respectively. If a code 'F' is inputted to a route at the last time and a code 'G' is inputted to a route at this time, R=7 is obtained by means of a processing of E1, and D=7-5=2 (difference value) by means of a processing of E2. Since the absolute value of D does not exceed '6', the shift processing becomes NO at step E3 and the processing is performed at step E5 for becoming S=5+2=7 (shift value). Although a sign of D and S is the same, |D| does not exceed '3' and |S| does not exceed '9' either, therefore, the processing becomes NO at step E6 and goes to step E8. Further, |S| does not exceed '12', the processing at E9 is not performed, therefore, a shift value becomes '7' in this case, and the code of accompaniment pattern data is shifted to the positive direction by 7 semitone in the root sound C.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic accompaniment apparatus for performing automatic accompaniment while changing the chords constituting an accompaniment according to the type of a chord inputted on a keyboard or the like.

[0002]

2. Description of the Related Art Conventionally, in an automatic accompaniment device, for example, an accompaniment pattern represented by a musical score in FIG. 9A is stored in a memory. The pitch of a chord when a C major is input as a chord. Further, as shown in FIG. 10A, “C” is stored in a table in another memory.
The root (root note) and the shift amount for each octave from to “B” are stored in correspondence with each other. This shift amount is “C” as shown in FIG.
The shift amount of the octave is set to "0", and the pitch of one octave centered on "C" is divided into a minus side and a plus side, and the absolute value increases as the distance from "C" increases. It is set in units.

When the automatic accompaniment is started, the accompaniment patterns stored in the memory are sequentially read out, and an accompaniment tone composed of chords is generated in accordance with the tone generation timing and pitch. When a chord other than the C major is input by pressing a key, the shift amount corresponding to the root of the chord is read out from the table, and the root of the chord of the accompaniment pattern is shifted by this shift amount. The chord constituent tones are also shifted accordingly, and a chord of this shifted pitch is generated at the timing of sounding the accompaniment pattern. Therefore, if you press the chord whose root is "F",
Since the root "F" is shifted by "+5", the root of the chord "C" of the accompaniment pattern is shifted by +5 semitones to "F", and the other chord components are also shifted to "F". The chord sound of F "is generated at the sound generation timing. Also, if you press the chord whose route is "G",
Since the root "G" is shifted by "-5", the root "C" of the chord of the accompaniment pattern is shifted by -5 semitones to become "G", and other chord components are also shifted. A "G" chord tone is generated at the sounding timing. Therefore, as shown in FIG. 9 (b), the key whose root is "F" is pressed at the time T2 without pressing the key at the time T1, and the code whose root is "G" is pressed at the time T3. When locked, the codes are C, F, G as shown
And will proceed.

[0004]

As described above, in the conventional automatic accompaniment apparatus, the relationship between the route and the shift amount is set in a table in advance, and when a chord is input on the keyboard, By shifting the chord root that is the basis of the accompaniment pattern by a fixed shift amount corresponding to the chord root of the input chord, the chord component sound of the specified chord is generated at the timing of the accompaniment pattern. ing. Therefore, as shown in the example shown in FIG. 9B, when the codes “F” and “G” are input at the time points T2 and T3, respectively, at the time point T2, “C” is increased by +5 semitones and T
At the third time point, a change of -5 semitones with respect to "C" causes a jump of a chord of 10 semitones (minor seventh) between "F" and "G". This jumping chord progression may not be a problem in harmony music, but is not a preferable chord progression form in general music, and is not preferable in terms of hearing.

The present invention has been made in view of such conventional problems, and has as its object to provide an automatic accompaniment apparatus capable of performing an automatic accompaniment without causing a continuous accompaniment sound to jump. Is what you do.

[0006]

According to the present invention, in order to solve the above-mentioned problem, an accompaniment pattern consisting of pitches to be generated when predetermined chord information is inputted is read out sequentially. Means, input means for inputting chord information, and shift means for shifting the pitch of the accompaniment pattern read by the reading means to a pitch corresponding to the root in the chord information input by the input means. In the automatic accompaniment apparatus having the above, the pitch difference between the root of the chord information used in the previous shift by the shift means and the root of the chord information used in the current shift is determined in the direction in which the pitch difference becomes smaller. Detecting means for detecting, and a shift amount and a shift to be shifted by the shift means this time based on the pitch difference detected by the detecting means, the direction, and the previously shifted pitch. Calculating means for calculating the direction, according to the calculated shift amount and the shift direction by the calculating means, and a control means for shifting the pitch of the accompaniment pattern in the shifting means.

In this configuration, the detecting means detects a pitch difference between the root of the chord information used for the previous shift and the root of the chord information used for the current shift. Is detected in the detection direction in which is smaller. In other words, the root has 12 pitches from "C" to "B" in semitone units in order of pitch. When detecting a pitch difference in this pitch direction (positive direction), "C" at both ends is used. To "B" have a pitch difference of 11 semitones. However, since the pitch “B” is also a pitch one semitone lower than the pitch “C”, when a pitch difference is detected with the reverse direction (minus direction) as the detection direction, the pitch difference between the two becomes one semitone, Therefore, in this case, the detecting means detects the pitch difference “one semitone”. Therefore, based on the detected pitch difference "one semitone" and the detection direction (reverse direction, minus direction) and the previously shifted pitch, the calculating means calculates the shift amount to be shifted this time and the shift direction. If the control means shifts the pitch of the accompaniment pattern to the shift means by the calculated shift amount and shift direction, a large pitch is generated between the previously shifted pitch and the currently shifted pitch. There is no difference.

Further, in the invention according to claim 2, the accompaniment pattern is constituted by a pitch of a chord and a sounding timing of the chord, and the shift means is a chord read by the reading means. Is shifted to a pitch corresponding to the root in the chord information input by the input means. Therefore, there is no large pitch difference between the chord shifted last time and the chord shifted this time, and the jump of the chord is prevented.

According to a third aspect of the present invention, the calculating means is configured to calculate the shift amount so as not to exceed a predetermined maximum shift amount. Preferably, the calculating means is configured to calculate the shift direction so as not to exceed a predetermined maximum shift amount. Therefore, the detecting means detects a pitch difference between the previously shifted pitch and the root of the chord information used in the current shift in a direction in which the pitch difference becomes smaller, and detects the pitch difference based on the detected pitch difference. Even if you shift sequentially,
The shift amount does not exceed the maximum shift amount, and is shifted in the reverse direction before exceeding the maximum shift amount.

[0010] In the invention according to claim 5, the maximum shift amount can be changed according to the accompaniment pattern. In the invention according to claim 6, the maximum shift amount is: It can be changed according to the timbre to be sounded based on the accompaniment pattern. Therefore, the range of the accompaniment pattern that changes with the input of the chord changes according to the type and timbre of the accompaniment pattern.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. In this embodiment, the present invention is applied to an electronic musical instrument, and this electronic musical instrument is provided with a keyboard 1 and a switch unit 2 as shown in the block diagram of FIG. The keyboard 1 is provided with a plurality of keys, and a key switch that is turned on when a key is pressed is provided for each key. The switch unit 2 is provided with various switches, such as a power switch and a volume switch, which are provided in a normal electronic musical instrument, and also includes a tone selection switch, an accompaniment pattern selection switch, a mode switch, an automatic An accompaniment start / stop switch and the like are provided.

The switch information from the keyboard 1 and the switch unit 2 is input to the CPU 3. The CPU 3 operates based on the input information, the program stored in the internal ROM, and the data stored in the storage device 4, executes all necessary processing in the electronic musical instrument, and controls the sound source 5. I do. That is, the CPU 3
By executing processing in accordance with the flow described later, the readout unit, the shift unit, the detection unit, the calculation unit, the control unit, and the like are configured in the present embodiment.
Is a waveform corresponding to the tone number in accordance with the instruction from the CPU 3, generates a musical tone waveform of the designated frequency, and the musical tone waveform is given to the sound system 6 including an amplifier and a speaker. The sound system 6 is configured to generate a musical tone having the specified tone and pitch at the timing specified by the sound system 6.

The storage device 4 stores a plurality of types of automatic accompaniment pattern data corresponding to accompaniment pattern numbers. Each automatic accompaniment pattern data is, for example, as shown in FIG.
As shown in the musical score, a chord is composed of a sounding timing indicated by a note of each chord, and a pitch of a chord when a C major is inputted as a chord by pressing a key. For the sake of simplicity, the automatic accompaniment pattern data shows only C major chords, but other types of chords may be mixed and shifted in the same manner as C major chords). Further, the CPU 4 has registers for storing the following data.

R: root of the current chord specified by the key depression P: root of the chord specified immediately before D: difference value between R and P S: pitch shift amount of accompaniment pattern a: accompaniment pattern number t: tone number MF: mode flag, "1" is stored when the automatic accompaniment mode is set, and "0" is stored when it is not set. AF: automatic accompaniment flag, "1" when the automatic accompaniment is in progress, stop When the process is executed, the CPU 3 sets the pitch C, C #, D,... In semitone units within one octave when executing the process.
, B are encoded into corresponding values of 0, 1, 2,..., 11, and these values are stored as roots in the registers R, P.

Next, the operation of this embodiment having the above configuration will be described with reference to the flowcharts shown in FIG.
That is, the CPU 3 starts the operation according to the general flow shown in FIG. 2 when the power switch is turned on, and executes an initialization process (step A1) to clear the above-described various registers. Subsequently, a switch process (step A2), a keyboard process (step A3), which will be described later,
The automatic accompaniment process (step A4) and other processes (step A5) are executed, and the loop of steps A2 to A5 is repeated while the power switch is on.

The switch processing (step A2) is performed according to the flow shown in FIG. 3, and it is monitored whether any switch provided in the switch unit 2 has been operated (step B1). If not,
Return to the general flow (FIG. 2). However, if any switch is operated, it is determined whether or not it is a tone selection switch (step B2). If any switch, the tone selected by operating this tone selection switch is determined. The number is stored in t (step B3), and a tone setting process is executed so that the tone generator 5 shapes the waveform of the selected tone at the time of sound generation (step B4).

If the operated switch is an accompaniment pattern selection switch (YES in step B5),
The accompaniment pattern number selected by operating the accompaniment pattern selection switch is stored in a (step B).
6), an accompaniment pattern setting process is executed to read out the accompaniment pattern data corresponding to the accompaniment pattern number from the storage device 4 with the start of the automatic accompaniment (step B)
7). Further, if the operated switch is a mode switch (YES in step B8), the MF is inverted (step B9).
Each time the mode switch is operated, it changes to "1" or "0".

If the operated switch is an automatic accompaniment start / stop switch (step B10)
Is YES), it is determined whether or not the MF is set (step B11). If the MF is not set and the automatic accompaniment mode is not set, the process proceeds to step B13 without performing the process of step B12, and if it is set, the AF is reversed (step B13). B12). Therefore, the automatic accompaniment flag AF
Is inverted only in the automatic accompaniment mode, and as described above, "1" indicates that the automatic accompaniment is in progress, and "0" indicates that the automatic accompaniment is stopped. Further, if the operated switch is not any of these switches, other switch processing corresponding to the operated switch is performed (step B).
13) Return to the general flow.

The keyboard processing (step A3) is performed according to the flow shown in FIG. 4, and scans the key switches provided on each key of the keyboard 1 to determine the state of each key based on the operated key switches. The key switch is identified (step C1), and if there is no change in the state of the key switch, the process returns to the general flow (FIG. 2). If the key switch changes from off to on and a key is pressed, it is determined whether or not a plurality of keys are pressed simultaneously (step C2). Then, it is determined whether or not the MF has been set (step C3). Then, as a result of the discrimination in step C3 and the above-described step C2, if a plurality of keys are depressed at the same time and the MF is set and the automatic accompaniment mode is set at this time, the process of step C4 is performed. No, return to general flow.

However, steps C2 and C
As a result of the determination in step 2, if the keys are not simultaneously depressed for a plurality of keys, and if the MF is reset and the automatic accompaniment mode is not set even if the keys are depressed simultaneously, the key corresponding to the depressed key is The sound generation at the pitch to be performed is instructed (step C4). That is, the CPU 3 generates a sound at the pitch at which the key is depressed.
, And the sound source 5 generates a musical tone waveform having a corresponding frequency, so that the sound system 6 generates a musical tone having a pitch corresponding to the key depression at a timing corresponding to the key depression in the tone subjected to the tone setting processing. . If a key release has occurred as a result of the determination in step C1, an instruction to mute the musical tone related to the released key is issued (step C5). When the tone generator 5 attenuates the corresponding musical sound waveform in accordance with the instruction, the musical sound corresponding to the key release generated from the sound system 6 is muted.

The automatic accompaniment process (step A4) is performed according to the flow shown in FIG. 5, and it is determined whether or not the mode flag MF is set (step D1). Returns to the general flow without performing the subsequent processing. If the mode flag MF is set and the automatic accompaniment mode is set, it is determined whether or not multiple keys are simultaneously pressed on the keyboard 1 (step D2). Proceeds to step D5 without performing the processing of steps D3 and D4. If the simultaneous pressing of a plurality of keys has occurred, it is determined whether or not the simultaneous pressing of the plurality of keys has been established as a code (step D).
4) If the condition is satisfied, shift processing (step D4) described later is executed. However, if the condition is not satisfied, the process of reading / sounding accompaniment pattern data is executed without executing the process of step D4 (step D5).

Accordingly, the reading and sounding processing of the accompaniment pattern data in step D5 is not established as a chord when there is no simultaneous pressing of a plurality of keys in the state of the automatic accompaniment mode, and even when there is a simultaneous pressing of a plurality of keys. In this case, the processing is performed without the shift processing (step D4). In this case, the accompaniment pattern setting processing (step B4) is performed in advance.
The accompaniment pattern data of the accompaniment pattern number set in step 7) is read out, and the tone generation timing and tone generation at the same pitch are instructed to the sound source 5. Therefore,
When the shift processing (step D4) is not performed, the chord sound is sequentially generated from the sound system 6 at the sounding timing of the accompaniment pattern of the preset accompaniment pattern number.

This shift processing (step D4) is performed according to FIG.
The flow of the chord from the keyboard is taken in and stored in R (step E1). That is, since the simultaneous pressing of a plurality of keys is established as a code by the above-described determination in step D3, the route of the established code is stored in the register R with a corresponding value of 0 to 11. Subsequently, the value stored in P in step E10 described later, that is, the root value of the code input by the immediately preceding key press, is subtracted from the value of R by the processing according to the previous flow, and The difference is calculated, and the difference between R and P is stored in the register D (step E).
2). By the processing in step E2, the pitch difference between the root of the previous input code and the current input code is stored in D.

Next, it is determined whether or not the absolute value of the value stored in D is greater than 6, that is, if a semitone is used as a unit, whether or not the pitch difference between the two is greater than 6. If there is, the process proceeds to step E5 without performing the process of step E4. However, if it exceeds 6, D / |
D | (| D | -12) is calculated, and the register D is updated with the calculation result (step E4). In the equation shown in step E4, D / | D | is used to influence the sign of the value stored in the register D in step E2 to the value of (| D | -12). The pitch difference between the previous route and the current route is calculated in a direction in which the pitch difference between the two routes becomes smaller.

That is, since the values of the routes stored in the registers R and P are 0 to 11,
Is stored in the register R and "0" is stored in the register R, the value of the route C is RP = 0-11 = 11, and the pitches of both are set. If the difference is detected in the direction in which the pitch decreases (minus direction), "1"
1 ". Since the value is greater than 6,
When the calculation of step E4 is performed,-(11-12) = 1, and this value "1" is a direction in which the pitch is increased (positive direction).
And the pitch difference between “B” and “C” in the above, so that the pitch difference between the previous route and the current route becomes smaller (shifted by one octave) by the processing of steps E2 to E4. Will be detected.

In the next step E5, the difference value stored in the register D in step E2 is added to the value in the register S storing the previous pitch shift amount of the accompaniment pattern and updated. Then, it is determined whether D × S> 0, | D |> 3, and | S |> 9 (step E6). In this step E6, D × S
> 0, it is determined whether or not the difference value stored in D and the value of the shift amount stored in S are the same.
D |> 3 and | S |> 9 indicate that a movement larger than “3” semitones is about to be made from the previous chord, and whether or not the planned shift amount from the reference “C” exceeds “9” semitones. Is determined. If any one of these three conditions is not satisfied, the process proceeds to step E8 without performing the processing of step E7, and the registers D,
The value stored in S is the same, the sign is the same, the movement is going to be larger than "3" semitones from the previous chord, and the shift amount from the current reference "C" exceeds "9" semitones. In this case, the process of step E7 is performed.

In the process of step E7, the same process as in the above-described step E4 is executed for the value of S, and the pitch shift amount of S is shifted by one octave by this process. Subsequently, whether or not the absolute value of the shift amount stored in S is greater than 12 when the process of step E7 is not performed and the process proceeds from step E6 without performing the process of step E7. Is determined (step E8), and if it exceeds 12, the same processing as step E7 is executed again (step E9). The process of step E9 is a process for limiting the maximum shift amount from the reference "C" to within 12 semitones, that is, within one octave up and down. If the shift amount is larger than 12 as a result of the determination in step E8, By performing the processing in step E9, the shift amount is suppressed within one octave above and below the reference "C". After a while
The value of the register R, which is the root of the current code, is stored in the register P, updated, and the process returns to the general flow.

Next, regarding the shift processing of FIG. 6 described above, C → F → G → F → A... G → B → C → A # →
A detailed description will be given on the assumption that keys are sequentially pressed on the keyboard 1 in the order of F # → E → D → C → A #.

(1) C → F If the root of the previous code is “C” and the root of the current code is “F”, R
= 5, and D = 5-0 = 5 by the processing in step E2.
(Difference value). Since the absolute value of the register D does not exceed "6", step E3 becomes NO and the process of step E5 is performed, and S = 0 + 5 = 5 (shift amount). Subsequently, the determination in step E6 is performed.
(Difference value and shift amount) have the same sign, and | D |
(The absolute value of the difference value) exceeds “3”, but | S |
Since (the absolute value of the shift amount) does not exceed “9”, the result of step E6 is NO, and the process proceeds to step E8.
Further, since | S | (absolute value of the shift amount) does not exceed “12”, the processing in step E9 is not performed, and
The process of step E10 is performed and the process returns. Therefore, in the case of (1), the shift amount is “5”, and the chord of the accompaniment pattern data is such that its root C is 5 in the plus direction.
Will be shifted by a semitone. Since the pitch shifted by 5 semitones in the plus direction of “C” is “F”, when a chord F is input, the accompaniment chord is converted into a chord F as shown in FIG. Step D in FIG.
5, the sound is processed.

(2) F → G If the route of the previous code is “F” and the route of the current code is “G”, R
= 7, and D = 7−5 = 2 by the processing in step E2.
(Difference value). Since the absolute value of the register D does not exceed "6", step E3 is NO and the process of step E5 is performed, so that S = 5 + 2 = 7 (shift amount). Subsequently, the determination in step E6 is performed.
(Difference value and shift amount) have the same sign, but | D |
(The absolute value of the difference value) does not exceed “3”, and | S |
Since (the absolute value of the shift amount) also does not exceed “9”, the result of step E6 is NO, and the process proceeds to step E8.
Further, since | S | (absolute value of the shift amount) does not exceed “12”, the processing in step E9 is not performed, and
The process of step E10 is performed and the process returns. Accordingly, in the case of (2), the shift amount is “7”, and the chord of the accompaniment pattern data is such that its root note C is 7 in the plus direction.
Will be shifted by a semitone. Since the pitch shifted by seven semitones in the plus direction of “C” is “G”, when a code G is input, as shown by a solid line in (2) of FIG.
The accompaniment chord is converted into a chord G, and the sound is processed in step D5 in FIG. Therefore, a jump of a chord of ten semitones (minor seventh) occurs between "F" and "G", as in the conventional device described above with reference to FIG. 10 and indicated by the dotted line in (2) of FIG. The pitch difference between them is only two semitones (major second), and the occurrence of jumping chord progression can be prevented, and a chord progression form that is preferable in general music and listening can be formed.

(3) G → F If the root of the previous code is “G” and the root of the current code is “F”, R
= 5, and D = 5-7 = −
2 (difference value). Since the absolute value of the register D does not exceed "6", step E3 is NO and the process of step E5 is performed, and S = 7-2 = 5 (shift amount)
Becomes When the determination in step E6 is continuously performed, D and S
Since the signs of (difference value and shift amount) are different, step E6 becomes NO and the process proceeds to step E8. Also, | S
Since | (absolute value of the shift amount) does not exceed “12”, the processing in step E9 is performed without performing the processing in step E9.
After performing the process of 10, the process returns. Therefore, in the case of (3), the shift amount is "5", and the chord of the accompaniment pattern data has its root C shifted by 5 semitones in the plus direction. Since the pitch shifted by 5 semitones in the plus direction of “C” is “F”, if a chord F is input, the accompaniment chord is changed to chord F as shown by a solid line in (3) of FIG. It is converted and the above-described step D5 in FIG.
Is generated.

(4) F → A If the route of the previous code is “F” and the route of the current code is “A”, R
= 9, and D = 9−5 = 4 by the processing in step E2.
(Difference value). Since the absolute value of the register D does not exceed "6", step E3 becomes NO and the process of step E5 is performed, so that S = 5 + 4 = 9 (shift amount). Subsequently, the determination in step E6 is performed.
The sign of (difference value and shift amount) is the same, and | D | (absolute value of difference value) exceeds “3”, while | S | (absolute value of shift amount) exceeds “9”. No, step E6 is NO, and the process proceeds to step E8. Also, |
Since S | (the absolute value of the shift amount) does not exceed "12", the process returns to step E10 without performing the process in step E9. Therefore, in the case of (4), the shift amount is "9", and the root note C of the chord of the accompaniment pattern data is shifted by nine semitones in the plus direction. Since the pitch shifted by 9 semitones in the plus direction of “C” is “A”, if the chord A is input, the accompaniment chord changes to the chord A as shown by the solid line in FIG. It is converted and the above-described step D5 in FIG.
Is generated. Therefore, as in the conventional device shown by the dotted line in FIG.
There is no jump of a semitone (minor 6th) chord, and the pitch difference between them is only 4 semitones (major 3rd). It is possible to form a chord progression form that is preferable in terms of hearing.

(5) G → B The root of the previous code is “G” (here,
If the root of this chord is “B”, R = 11 by the processing of step E1 and D = 11 by the processing of step E2. -7 = 4 (difference value). Since the absolute value of the register D does not exceed "6", the result of step E3 is NO, the processing of step E5 is performed, and S =
7 + 4 = 11 (shift amount). Continue with step E
6, the signs of D and S (difference value and shift amount) are the same, | D | (absolute value of the difference value) exceeds “3”, and | S | Since the absolute value also exceeds “9”, the result of step E6 is YES, and the process proceeds to step E7, where S = + (11−12) = − 1 (shift amount).
Is calculated. Therefore, | S | (the absolute value of the shift amount)
Does not exceed "12", the process of step E10 is performed without performing the process of step E9, and the process returns. Therefore, in the case of (5), the shift amount is "-1", and the chord of the accompaniment pattern data has its root C shifted by one semitone in the minus direction.
Since the pitch shifted by one semitone in the minus direction of "C" is "B", when the code B is input, the accompaniment code is converted to the code B, and the above-mentioned step D in FIG.
5, the sound is processed.

(6) B → C If the route of the previous code is “B” and the route of the current code is “C”, R
= 0, and D = 0-11 =
-11 (difference value). The absolute value of register D is "6"
Is exceeded, step E3 becomes YES and the processing of step E4 is performed, where D =-(11-12) =
1 (difference value). Next, the process of step E5 is performed, and S = −1 + 1 = 0 (shift amount). If the determination in step E6 is continued, the signs of D and S (difference value and shift amount) are different, so that step E6 becomes NO and the process proceeds to step E8. Since | S | (the absolute value of the shift amount) does not exceed “12”, step E
Without performing the processing of step 9, the processing of step E10 is performed and the routine returns. Therefore, in the case of (6), the shift amount is “0”, and the root of the chord of the accompaniment pattern data is shifted by 0 semitone. This "C"
Since the pitch shifted by one semitone is "C" as it is, if the code C is input, the accompaniment chord is subjected to the tone generation processing in step D5 of FIG.

(7) C → A # If the route of the previous code is “C” and the route of the current code is “A #”, R = 10 by the processing of step E1, and the processing of step E2 D = 10−
0 = −10 (difference value). Since the absolute value of the register D exceeds "6", the step E3 becomes YES, the processing of the step E4 is performed, and D = + (10-1
2) = − 2 (difference value). Next, the process of step E5 is performed, and S = 0-2 = -2 (shift amount). When the determination in step E6 is subsequently performed, the signs of D and S (the difference value and the shift amount) are the same, but | D | (the absolute value of the difference value) does not exceed “3”.
Is NO, and the process proceeds to Step E8. Since | S | (absolute value of shift amount) does not exceed “12”,
The process returns to step E10 without performing step E9. Accordingly, in the case of (7), the shift amount is "-2", and the chord of the accompaniment pattern data has its root C shifted by two semitones in the minus direction. Since the pitch shifted by two semitones in the minus direction of "C" is "A #", if a code A # is input, the accompaniment code is converted into a code A #, and the above-mentioned step D5 in FIG. Is generated.

(8) A # → F # If the route of the previous code is “A #” and the route of the current code is “F #”, R = 6 by the processing of step E1 and step E2 D = 6-1
0 = −4 (difference value). Since the absolute value of the register D does not exceed "6", step E3 is NO and the processing of step E5 is performed, and S = -2-4 =-
6 (shift amount). Subsequently, in step E6, the signs of D and S (the difference value and the shift amount) are the same, and | D | (the absolute value of the difference value) exceeds "3". Since (the absolute value of the shift amount) does not exceed “9”, the result of step E6 is NO, and the result of step E6 is NO.
Proceed to 8. | S | (the absolute value of the shift amount) is “1”.
Since the value does not exceed 2 ", the process returns to step E10 without performing the process in step E9. Therefore, in the case of (8), the shift amount is"-".
6 ", and the chord of the accompaniment pattern data is the root note C
Is shifted six semitones in the minus direction. The pitch shifted six semitones in the minus direction of this “C” is
Since it is "F #", if the chord F # is inputted, the accompaniment chord is converted into the chord F #, and the sound is processed in the above-described step D5 in FIG.

(9) F # → E If the route of the previous code is “F #” and the route of the current code is “E”, R = 4 by the processing of step E1, and the processing of step E2 D = 4-6 =
-2 (difference value). Since the absolute value of the register D does not exceed "6", step E3 becomes NO and the process of step E5 is performed, so that S = -6-2 = -8 (shift amount). Subsequently, the determination in step E6 is performed.
The signs of D and S (difference value and shift amount) are the same, but |
Since D | (absolute value of the difference value) does not exceed "3", step E6 is NO, and the process proceeds to step E8.
Further, since | S | (absolute value of the shift amount) does not exceed “12”, the processing in step E9 is not performed, and
The process of step E10 is performed and the process returns. Therefore, in the case of (9), the shift amount is “−8”, and the chord of the accompaniment pattern data has its root C shifted by 8 semitones in the minus direction. Since the pitch shifted by eight semitones in the minus direction of "C" is "E", when the code E is input, the accompaniment chord is converted into the code E, and the sound generation processing is performed in step D5 of FIG. Is done.

(10) E → D If the root of the previous code is “E” and the root of the current code is “D”, R
= 2, and D = 2−4 = − by the processing in step E2.
2 (difference value). Since the absolute value of the register D does not exceed "6", step E3 becomes NO and the process of step E5 is performed, so that S = -8-2 = -10 (shift amount). Subsequently, the determination in step E6 is performed.
The signs of D and S (difference value and shift amount) are the same, but |
Since D | (absolute value of the difference value) does not exceed "3", step E6 is NO, and the process proceeds to step E8.
Further, since | S | (absolute value of the shift amount) does not exceed “12”, the processing in step E9 is not performed, and
The process of step E10 is performed and the process returns. Therefore, in the case of (10), the shift amount is “−10”, and the chord of the accompaniment pattern data has its root C shifted by 6 semitones in the minus direction. Since the pitch shifted by 10 semitones in the minus direction of "C" is "D", when the code D is input, the accompaniment chord is converted into the code D, and the sound generation processing is performed in step D5 in FIG. Is done.

(11) D → C If the root of the previous code is “D” and the root of the current code is “C”, R
= 0, and D = 0-2 = − by the processing of step E2.
2 (difference value). Since the absolute value of the register D does not exceed "6", step E3 becomes NO and the process of step E5 is performed, so that S = -10-2 = -12 (shift amount). Subsequently, the determination in step E6 is performed. The signs of D and S (difference value and shift amount) are the same, but | D | (absolute value of the difference value) does not exceed “3”. Is NO, and the process proceeds to Step E8. In addition, since | S | (the absolute value of the shift amount) does not exceed “12”, the process returns to step E10 without performing step E9. Therefore, in the case of (9), the shift amount is "-12", and the chord of the accompaniment pattern data has its root C shifted by 12 semitones in the minus direction. The pitch shifted by 12 semitones in the minus direction of this “C” is
Since the code is "C", if the chord C is input, the accompaniment chord is converted into the chord C, and the tone generation process is performed in step D5 in FIG.

(12) C → A # If the route of the previous code is “C” and the route of the current code is “A #”, R = 10 by the processing of step E1, and the processing of step E2 D = 10−
0 = 10 (difference value). Since the absolute value of the register D exceeds "6", the step E3 becomes YES, the processing of the step E4 is performed, and D = + (10-1
2) = − 2 (difference value). Next, the process of step E5 is performed, and S = -12-2 = -14 (shift amount). When the determination in step E6 is subsequently performed, the signs of D and S (the difference value and the shift amount) are the same, but | D | (the absolute value of the difference value) does not exceed “3”. Is NO, and the process proceeds to Step E8. Also, | S
Since | (absolute value of shift amount) exceeds “12”, the process of step E9 is performed, and S = − (14-1)
2) = − 2 (shift amount). Therefore, this (1)
In the case of 2), the shift amount is "-2", and the chord of the accompaniment pattern data has its root C shifted by two semitones in the minus direction. 2 in the minus direction of this "C"
Since the pitch shifted by one semitone is "A #", if a chord A # is input, the accompaniment chord is converted to a chord A #, and the tone generation process is performed in step D5 of FIG.

At this time, the chord of the accompaniment pattern data in (11) is shifted by 12 semitones in the root C in the minus direction, so that the reference "C" which is the lower limit of the shift amount in the present embodiment. Although it has reached “C”, which is one octave lower, the shift amount and shift direction are suppressed within one octave from the reference “C” by calculating “−2” by the processing in step E9. Therefore, even if the shift amount is calculated based on the pitch difference between the pitch of the route used for the previous shift and the pitch of the route used for the current shift, the chord of the accompaniment is the upper and lower It does not exceed the octave (12 semitones), and the fluctuation range of the accompaniment pitch can be properly maintained.

FIG. 8 shows another embodiment of the present invention. In this embodiment, the CPU 3 further uses a register for storing the following constants.

Xa, Ya: constants for limiting the pitch shift amount of the accompaniment pattern a Zt: constants for limiting the pitch shift amount of the timbre of the timbre number t The constants stored in the registers Xa, Ya are The Zt is a different value according to the accompaniment pattern selected by operating the accompaniment pattern selection switch provided on the switch unit 2, and Zt is a value different according to the timbre selected by operating the timbre selection switch. is there.

In this embodiment, the shift processing (step D4) is performed according to the flow shown in FIG. In the flow shown in FIG.
1 to F5, F7, F9, and F10 are the same as those in FIG.
Steps E1 to E5, E7, E9,
It is the same as the processing of E10, and only the processing of steps F6 and F8 is different. Then, in step F6 different from the flow of FIG. 6, D × S>, | D |> Xa, and | S |>
It is determined whether it is Ya. At this time, since different values are set for Xa and Ya according to the selected accompaniment pattern, the range for limiting the shift amount changes according to the accompaniment pattern by the process of step F6. . In step F8, it is determined whether or not | S |> Zt. Since Zt is set to a different value according to the selected timbre, the range in which the shift amount is limited depends on the timbre. Will also change.

That is, with respect to the accompaniment pattern, there are those which do not affect the musical performance even if the accompaniment sound is changed in a wide range and those which are generally changed only in a narrow range. There are those that change the accompaniment sound in a wide range and those that change the accompaniment sound only in a narrow range according to the type. Therefore, steps F6 and S
By making the values of Xa, Ya, and Zt used in step 8 variable according to the accompaniment pattern and the timbre, the accompaniment sound is changed according to the designated chord within an appropriate range corresponding to the accompaniment pattern and the timbre. It becomes possible.

[0046]

As described above, according to the present invention, the pitch difference between the root of chord information used in the previous shift and the root of chord information used in the current shift is reduced. In this direction, based on the detected pitch difference, the detected direction and the previously shifted pitch, the shift amount and the shift direction to be shifted this time are calculated, and the pitch of the accompaniment pattern is input. The chord is shifted by the root of the chord. Therefore, there is no significant difference in pitch between the previously shifted pitch and the currently shifted pitch, and the occurrence of a jumping accompaniment sound is prevented, and a musically and audibly favorable pitch change. The accompaniment sound can be generated in the state. Further, since the root of the read chord is shifted to the pitch of the root of the input chord information, a chord progression which is a problem in music fields other than the harmony is accompanied. The automatic accompaniment can be advanced without any need.

Further, since the shift amount and the shift direction are calculated so as not to exceed the predetermined maximum shift amount, the pitch between the previously shifted pitch and the root of the chord information used in the current shift is calculated. Even if the shift is performed sequentially due to the height difference, the shift amount does not exceed the maximum shift amount, and it is possible to shift in the reverse direction before exceeding the maximum shift amount. Therefore, the fluctuation range of the accompaniment pitch can be appropriately maintained, and the fluctuation of the pitch can be suppressed by changing the shift direction before exceeding the maximum shift amount. Furthermore, since the maximum shift amount can be changed according to the type and tone of the accompaniment pattern,
The accompaniment sound can be changed in accordance with a designated chord within a different appropriate gamut according to the accompaniment pattern or timbre.

[0048]

[Brief description of the drawings]

FIG. 1 is a block diagram of an electronic musical instrument to which an embodiment of the present invention is applied.

FIG. 2 is a flowchart showing a general flow of the embodiment.

FIG. 3 is a flowchart illustrating a processing procedure of a switch processing;

FIG. 4 is a flowchart showing a processing procedure of keyboard processing.

FIG. 5 is a flowchart showing a processing procedure of an automatic accompaniment process.

FIG. 6 is a flowchart illustrating a processing procedure of a shift processing.

FIG. 7 is a music chart showing the pitch shifted in the present embodiment and the pitch shifted by the conventional device.

FIG. 8 is a flowchart showing a processing procedure of a shift processing according to another embodiment of the present invention.

FIG. 9 is a musical score diagram showing a relationship between a pitch of an accompaniment pattern and a pitch of an accompaniment to be generated.

FIG. 10 is an explanatory diagram showing a relationship between a route and a shift amount of a conventional automatic accompaniment device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Keyboard 3 CPU 4 Storage device

Claims (6)

[Claims] 1. A reading means for sequentially reading an accompaniment pattern consisting of pitches to be generated when predetermined chord information is input; an input means for inputting chord information; and an accompaniment pattern read by the reading means. Shift means for shifting the pitch of the chord information to the pitch corresponding to the root of the chord information input by the input means.In the automatic accompaniment apparatus, Detecting means for detecting a pitch difference between a root note and a root note of chord information used at the time of this shift in a direction in which the pitch difference becomes smaller; and the pitch difference detected by the detecting means, the direction, and the Calculating means for calculating a shift amount to be shifted this time and a shift direction based on the pitch shifted last time; and a shift amount calculated by the calculating means. Control means for causing the shift means to shift the pitch of the accompaniment pattern in accordance with the shift direction and the shift direction. 2. The accompaniment pattern includes a pitch of a chord and a sounding timing of the chord, and the shift means receives a root of the chord read by the reading means by the input means. 2. The automatic accompaniment apparatus according to claim 1, wherein the pitch is shifted to a pitch corresponding to a root in chord information. 3. The automatic accompaniment apparatus according to claim 1, wherein said calculating means calculates the shift amount so as not to exceed a predetermined maximum shift amount. 4. The automatic accompaniment device according to claim 1, wherein the calculating means calculates the shift direction so as not to exceed a predetermined maximum shift amount. 5. The automatic accompaniment device according to claim 3, wherein the maximum shift amount can be changed according to the accompaniment pattern. 6. The automatic accompaniment apparatus according to claim 3, wherein the maximum shift amount can be changed in accordance with a tone to be generated based on the accompaniment pattern.