JPS6032879B2 - automatic accompaniment device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an automatic accompaniment device having a large number of chords and without interruptions in sound due to interruptions in rhythm selection, etc.

The circuit configuration of a subordinate automatic base or automatic arpeggio is shown in FIG.

In the figure, a chord detection circuit 2 detects a chord played on an accompaniment keyboard I, and outputs a root tone signal and a chord signal representing the type of chord. For example, when performing automatic bass or automatic arpeggio accompaniment for five types of chords: major, minor, seventh, augment, and diminutive, the daughter tone signals are root, 3b, 3rd, 5b, 5th, and 6b.
Eight encoders 3 for degrees, 6 degrees, and 7b degrees convert the signal into signals corresponding to the respective degrees. On the other hand, a rhythm pulse generating circuit 4 generates a read pulse and an attack pulse for reading out a read only memory (ROM) 5. In the ROM 5, the stored contents are switched according to the type of code according to the code signal from the code detection circuit 2.
By the read pulse from the rhythm pulse generation circuit 4,
Outputs a selection signal according to the type of code. Based on the selection signal from the ROM 5, the selection circuit 6 selects the signals from the encoder 3 and sequentially sends them to the tone gate 7. For example, if a major is designated by the code signal, the selection circuit 6 selectively outputs signals of the root, 3rd, 5th, 6th, and 7b degrees. The musical tone gate 7 allows the scale signal to pass through according to the signal selected by the selection circuit 6, and then outputs the tone signal.
The amplitude is controlled by the attack pulse from the rhythm pulse generating circuit 4 in the loop circuit 8, and the sound is emitted through the filter 9, the amplifier 10, and the speaker 11. In this conventional configuration, as the number of types of codes increases, the ROM 5 needs to have the same number of storage contents as the number of code types, making the ROM complex and expensive. Furthermore, as the types of codes increase, the number of encoders 3 also increases, and the number of wires increases accordingly, as well as the number of bits of the selection circuit 6, making the configuration quite complex. Furthermore, when the bass or arpeggio progression spans octaves, it is difficult to control the octave. In response, the present applicant has proposed, in a separate application, an automatic accompaniment device with a simple configuration in which the contents of the ROM, the wiring of the integrated circuit, etc. do not change much even if the types of chords increase. In other words, the ROM has 1
This system stores patterns related to different types of chords and converts them into patterns related to various chords by combining them with an external circuit such as a note conversion circuit.The details are explained in the embodiments of the present invention. Furthermore, one of the problems with conventional automatic accompaniment devices is that when switching rhythms, that is, when selecting a new rhythm or when automatic accompaniment is stopped, discontinuities occur in the accompaniment sound and interruptions in sustain occur. exist.

SUMMARY OF THE INVENTION An object of the present invention is to provide an automatic accompaniment device that has a large number of chords that do not cause discontinuities or interruptions in accompaniment tones when selecting a rhythm or the like.

In order to achieve the above object, the automatic accompaniment device of the present invention stores note name information and attack information, and outputs note name signals and attack signals in binary numbers according to the output of a counter calculated by a clock and the input of a pattern selection switch. A storage circuit, means for deriving a scale signal corresponding to a pitch name signal from the storage circuit, an envelope circuit for controlling the amplitude of the scale signal from the means using the attack signal, and a musical tone for converting the output of the envelope circuit into a musical tone. In an automatic accompaniment device comprising a conversion circuit, a latch circuit is provided on the pitch name signal output side of the memory circuit to store the pitch name signal by an attack signal from the memory circuit, so that the memory can be stored by changing the input of the pattern selection switch. The present invention is characterized in that even if the pitch name signal of the circuit is changed, the pitch name signal does not change until the next attack signal output from the storage circuit is generated.

FIG. 2 is an explanatory diagram showing the configuration of an embodiment of the present invention, and shows an overall block diagram of an automatic accompaniment device comprising an automatic bass circuit and an automatic arpeggio circuit.

In the figure, during normal accompaniment, a chord played on the accompaniment keyboard opens the musical tone gate 23 in response to a key depression signal from the accompaniment keyboard circuit 21, allowing a scale signal corresponding to the key depression to pass through. The scale signal that has passed through the musical tone gate 23 is sent to the gate 24.
At this time, a rhythm signal is generated by the rhythm pulse from the rhythm pattern generation circuit 59 and is transmitted through the filter 25 and the amplifier 26, and at the same time, the rhythm signal is transmitted from the rhythm pattern generation circuit 59 through the rhythm blue source 60 and the amplifier 61, and is emitted from the speaker 62. be heard. On the other hand, the key press signal is given to the chord detection circuit 22, which detects the root note and chord type and sends it to the automatic bass circuit and automatic arpeggio circuit. In these circuits, the starting switch SW. By closing a, a reset signal is output from the differentiating circuit 27, and the counters 29 and 30 driven by the clock generator 28 and the rhythm pattern generating circuit 59 are reset, so that they operate synchronously. First, the automatic base circuit uses the counter 30
The contents of the ROM 32 are read out by the output.

The ROM 32 stores an automatic bass pattern corresponding to C major, Japanese, and Japanese, and outputs a pitch name signal as a binary number according to the pattern. Table 1 shows these pitch name signals in 4-bit binary numbers. Various patterns can be obtained by changing the contents of the ROM 32 according to the type of rhythm, such as samba, mambo, ballad, etc., by inputting the automatic bass pattern outputted from the ROM 32 using a pattern selection switch (not stored). This pitch name signal is stored in the latch circuit 36 using the attack signal from the ROM 32 as a latch pulse.

This attack signal is applied to a latch circuit 36 and an envelope circuit 54 via a gate circuit 34, as shown in Table 1 and Table 2.

In this case, the gate circuit 34 is connected to the performance switch SW. This allows the attack signal to pass when b2 is closed. That is, starting switch SW. a, reset the counter 30, and read the bass pattern from the ROM 32, the performance switch SW. Unless b2 is closed, no attack signal is applied to the envelope circuit 54 and no musical tone is generated. Now, the note name signal stored in the latch circuit 36 is input to the note conversion circuit 39. Here, the chord signal from the chord detection circuit 22 is converted into a pitch name signal corresponding to the type of chord. Table 2 shows how notes are converted depending on the type of chord, typically for the bass progression in a swing rhythm. The pitch name signal corresponding to the type of chord is then added to the root tone signal from the chord detection circuit 22 in an adding circuit 41. The root signal is also output as a 4-bit binary number as shown in Table 1. As an example, Table 3 shows the adder 4 when the root note is F"010r.
1 shows the relationship between input and output. Table 3: The 5-bit pitch name signal added to the wolf green signal by the addition circuit 41 is 16
It is converted into a decimal number by a decimal-to-decimal conversion circuit 43.

Table 4 shows the input/output relationship of this 16-decimal conversion circuit. The most significant of the 5 bits is carried up by the numerical value 13, and this carry signal is sent to the gate 52, and the lower 4 bits are sent to the tone gate 47.

A fourth table tone gate 47 derives a scale signal corresponding to the lower four bits of the fourth table output.

The derived scale signal is frequency-divided by 1/2 and 1/4 by a frequency dividing circuit 50, and is inputted to a gate 52, respectively.

At the gate 52, the 1/2 frequency division output and the 1'4 frequency division output are selected by "0" and "1" of the aforementioned carry signal from the 1 mirror Hayabusa-12 conversion circuit 43, and the envelope The signal is sent to circuit 54. Enbe. The loop circuit 54 controls the amplitude of the scale signal using the aforementioned attack signal. Thereafter, the sound is emitted through a filter 56, an amplifier 58, and a speaker 63. Next, the automatic arpeggio circuit will be explained. Similarly to the automatic base circuit, the ROM 31 is activated by the output of the counter 29.
Read out. The ROM 31 stores an albeggio pattern corresponding to the C major chord.
Outputs bit binary numbers and octave signals in 2-bit binary numbers. Here, in the case of albeggio, four types of note name signals can be output with 2 bits, but this is because albeggio usually consists of only three or four tones that make up a chord.
Since the albeggio spans several octaves, four types of octave signals are prepared. Albeggio patterns can be changed to RO using a pattern selection switch that changes the pattern depending on the rhythm, such as mambo, swing, march, etc.
It is also possible to obtain various patterns by switching the contents of M31. These pitch name signals and octave signals are R
The attack signal from the OM 31 is stored in the latch circuit 35 as a latch pulse. Here, the gate circuit 33 is connected to the performance switch SW. This is to allow the attack signal to pass when the bl is closed. That is, as in the automatic base case, the start switch SW. a, reset the counter 29, and read out the pitch name signal and octave signal of the albeggio pattern from the ROM 31, even if the performance switch SW. b
Unless l is closed, no attack signal is given to the envelope circuit 53 and no arpeggio sound is generated. Now, the 2-bit pitch name signal stored in the latch circuit 35 is input to the code conversion circuit 37, where it is converted into 4-bit pitch name signals of three types, C, E, and G. Further, this pitch name signal is converted by the note conversion circuit 38 into a pitch name signal corresponding to the chord type of the chord signal from the chord detection circuit 22. Fifth
The table shows an example in which a 2-bit pitch name signal is converted into a 4-bit pitch name signal depending on the type of chord. Table 5 The pitch name signal thus converted into 4 bits is then added to the root note signal from the chord detection circuit 22 in an adder circuit 401.

This adder circuit 40 is the adder circuit 4 in the automatic base circuit.
It is the same as 1. The 5-bit 16 pitch name signals added to the 16 pitch notes in the adder circuit 40 are converted into 5-bit hexadecimal numbers in the 16-bit hexadecimal conversion circuit 42 using the input/output relationships shown in Table 4 and the method of the same machine. The musical tone gate 46 derives a corresponding scale signal. The derived scale signal is divided into four types of division ratios 1/2, 1/4, 1/&1/ in the frequency dividing circuit 49.
The frequency is divided into 16. On the other hand, 2 stored in the latch circuit 35
The bit octave signal is converted into 16-12 bits by the adder circuit 48.
It is added to the most significant carry signal from the decimal conversion circuit 42,
The signal from the frequency dividing circuit 49 is subjected to octave control at the gate 51 and selectively derived. The amplitude of the signal passing through the gate 51 is controlled by an attack signal in an envelope circuit 53, and the sound is emitted through a filter 55, an amplifier 57, and a speaker 62. Next, a detailed view of the main parts of the embodiment shown in FIG. 2 will be explained.

FIG. 3 shows a specific circuit from the clock generator 28 in FIG. 2 to the latch circuit 36 in the automatic base circuit and up to the latch circuit 35 in the automatic arpeggio circuit, and these circuits are common to both.

Starting switch SW. When a is closed, the delay circuit 116 and NA
A trigger pulse is generated by the ND circuit 1 1 1 and the counters 30 and 29 are reset. Count evening 30, 29
is the first counter (flip-flop FFIOI~FF
I05) and second counters FFI06 to FFIIO, the contents of ROM32 and 31 are read out by the Q outputs C, to C5 of each FF of the second counter, and in the case of automatic bass, the 4-bit note name is sent to the output terminal. Signals (1 to 4) and an attack signal are output, and in the case of automatic arpeggio, a 2-bit note name signal (1, 2), a 2-bit octave signal (1, 2), and an attack signal are output. These pitch name signals (1 to 4) or pitch name signals (1, 2) and octave signals (1, 2) are connected to the latch circuits 36, 35, which are the main parts of the present invention, that is, the D-type F
Enter each D state of F121 to 124 and press the performance switch S.
W. If b is closed, the attack signal is inverted via the NAND circuits 1 1 2, 1 13, and each D-type FF 1
input as a latch signal to the C terminals 21 to 124, and store the pitch name signal or octave signal in the D state;
The signal is sent to note conversion circuits 39 and 38 at the next stage. FIG. 4 shows a timing chart of input and output of the latch circuits 36 and 35.

The operation of the latch circuit 36 will be briefly described with reference to the figure. Now, 4-bit note name signal (1 to 4) from ROM32 output
Taking an example of the waveform of SW. and the corresponding attack signal, start switch SW. a and performance switch SW. It is assumed that b is turned on at the time shown. As a result, the performance switch S
W. The outputs (1 to 4) of the latch circuit 36 store the 4-bit note name signal (1 to 4) output from the ROM 32 by the attack signal after b is turned on, and store this until the next attack signal comes. and continue sending it out. In this way, the accompaniment sound will not be interrupted in the middle. The above-mentioned attack signal is further sent to envelope circuits 54 and 53 through a NAND circuit 113. Further, the pattern selection switch terminal specifies the type of rhythm, such as rock, waltz, mambo, swing, ballad, etc. In this case, a priority circuit 117 is provided that determines the priority order when these rhythms are designated simultaneously. ROM32, 31 terminal CTR (
The states of address counter) mode 3, double tempo, and PD (pre-divider) mode 3 change. For example, if it is locked, PD mode 3 becomes "1" and NAND circuit 1
15, the first counter is ternary corrected, and if it is a swing, CTR mode 3 becomes "1" and NAND circuit 1
14, the second counter is ternary corrected, and if it is a waltz, PD mode 3 and CTR mode 3 become "1", and the first,
Perform ternary correction on the second counter. Further, the double tempo is set to "1" in accordance with the rhythm, and the FFI05 is operated as an inverter. Table 6 shows an example of the number of counters for one pattern of the first counter and the second counter in pattern selection corresponding to each rhythm. As mentioned above, starting switch SW. a and performance switch SW. Since it has two control means of starting switch SW.b. a, the rhythm pattern generation circuit, automatic bass circuit, and automatic arpeggio circuit all operate in synchronization, and then the performance switch SW. By using b, it is possible to obtain a musical tone from a desired circuit.

In the present invention, since the latch circuits 36 and 35 are provided at the outputs of the ROMs 32 and 31, even when a new rhythm is selected or automatic performance is stopped, the immediately preceding pitch name signal No. There is no inconvenience that the past changes or the sustain is interrupted.

As explained above, according to the present invention, the memory circuit (RO
A latch circuit is provided on the output side of M), and by storing a note name signal in the latch circuit using an attack signal from the memory circuit, the note name signal sent from the memory circuit to the note conversion circuit can be used to select a new rhythm, etc. Even if the accompaniment is interrupted at 1 o'clock, the previous note name signal is held in the latch circuit, and that note name signal is continuously sent out until the next attack signal arrives, so the accompaniment note may be interrupted in the middle. The sound does not change, and natural accompaniment sound changes can be obtained.

In the example, a case was shown in which the present invention was applied to an automatic accompaniment device consisting of an automatic bass circuit and an automatic arpeggio circuit proposed separately, but a scale signal corresponding to a note name signal from a memory circuit is derived, and an envelope is added using an attack signal. The present invention can be applied to any automatic accompaniment device that converts music into musical tones. Further, although the main part of the present invention is a latch circuit, the present invention can be applied even if the latch circuit is replaced with a register or the like having the same function.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of a conventional example, FIG. 2 is an explanatory diagram showing the configuration of an embodiment of the present invention, FIG. 3 is a detailed explanatory diagram of the main part of the embodiment of FIG. 2, and FIG. This is a timing chart for explaining the operation of the figure. In the figure, 21 is an accompaniment keyboard circuit, 22 is a chord detection circuit, 23 is a tone gate, 24 is a gate, and 25 is a timing chart for explaining the operation of the figure.
is a filter, 26 is an amplifier, 27 is a differential circuit, 28 is a clock generator, 29 and 30 are counters, 31 and 32 are memory circuits (ROM), 33 and 34 are gates, 35 and 36 are latch circuits, and 37 is a code conversion circuit, 38 and 39 are note conversion circuits, 40 and 41 are addition circuits, 42 and 43 are la
Hayabusa-decimal conversion circuit, 46, 47 are musical tone gates, 48 is an addition circuit, 49, 5-way frequency divider, 51, 52 are gates, 53, 54 are envelope circuits, 55, 56 are filters, 57, 58 and 61 are amplifiers, 59 is a rhythm pattern generation circuit, 60 is a rhythm sound source, and 62 and 63 are speakers b Fig. 1 Fig. 3 Fig. N Ship Fig. 4

Claims (1)

[Claims] 1. A memory circuit that stores note name information and attack information and outputs note name signals and attack signals in binary according to the output of a counter counted by a clock and the input of a pattern selection switch, and a note name signal from the memory circuit. An automatic accompaniment device comprising means for deriving a scale signal corresponding to a scale signal, an envelope circuit for controlling the amplitude of the scale signal from the means using the attack signal, and a musical tone conversion circuit for converting the output of the envelope circuit into a musical tone. By providing a latch circuit on the pitch name signal output side of the circuit that stores the pitch name signal by an attack signal from the memory circuit, the pitch name signal of the memory circuit can be changed by changing the input of the pattern selection switch. Also, an automatic accompaniment device characterized in that the pitch name signal does not change until the next attack signal output from the memory circuit is generated.