JPS5943759B2 - automatic rhythm accompaniment device - Google Patents

Description

[Detailed Description of the Invention] The present invention detects that a key is pressed on a melody performance keyboard, selects and outputs the necessary accompaniment sound, and generates the accompaniment by passing pulses from a rhythm pulse generator for each measure. This invention relates to an automatic rhythm accompaniment device that controls sound.

The conventional automatic rhythm accompaniment device, as shown in Fig. 4A, operates a key to generate an accompaniment sound when a rhythm pulse occurs on the first beat of one bar and while that pulse is being generated. Ability to obtain accompaniment sound (When playing a song where the fourth beat is a rest, or because the key operation is delayed due to beginners, the desired accompaniment sound can be obtained if the key is operated after the pulse disappears.) The present invention improves the above-mentioned drawbacks and obtains the desired accompaniment sound by detecting a pressed key even if the key is not pressed at the first beat in the measure. The purpose of the present invention is to provide an automatic rhythm accompaniment device that can perform automatic rhythm accompaniment by storing the note name of a key pressed on a melody keyboard in a memory circuit, outputting a code corresponding to the memorized note name, and outputting a code corresponding to the memorized note name. In the automatic rhythm accompaniment device of the type that opens and closes a gate corresponding to a rhythm pulse from a rhythm pulse generating circuit by a rhythm pulse from a rhythm pulse generating circuit to generate an accompaniment sound according to a chord corresponding to the note name of the pressed key, the melody keyboard key press signal detecting means for detecting a key press and outputting a detection signal and storing the note name of the key by the press key in the memory circuit by the key press detecting operation; and detection from the key press signal detecting means. The signal and the first pulse of every l measure from the rhythm pulse generation circuit are input, and the operation signal is output by the human input of the detection signal.The inversion operation signal is output by the input of the first pulse. and a key press signal detection control means for outputting the key press signal, and the key press signal detection means performs the key press detection operation and the storage by inputting the operation signal from the key press signal detection control means. Stopping the memory action to the circuit, and starting the key press detection operation and the memory action to the memory circuit by inputting the inversion operation signal, detecting the first key press in l measure, and detecting the first key press in one measure. It is characterized by memorizing the pitch names of keys.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments of the present invention shown in the drawings will be described in detail below. FIG. 1 is a diagram showing the embodiment mainly from the program e, in which 1 is a group of key switches that operate in conjunction with a melody playing keyboard, 2 is a memory circuit, 3 is a circuit for selecting the tonality of the piece of music to be played, and 4 5 is a key press signal detection circuit, 5 is a delay time trap 6 is an inversion circuit, 5, 6 and r constitute a key press signal detection control means, 7 is a set circuit, 8 is a chord gate, 9 is a chord tone 10 is the rhythm generating circuit (rhythm)
, 11 is an amplifier, and 12 is a speaker. Note that the word "minor" in contrast to the chord gate 8r indicates the signal path used when switching the major chord of the accompaniment to the minor chord. In this embodiment, a circuit consisting of a key press signal detection circuit 4, a memory circuit 2, a key switch group 1, etc. constitutes the key press signal detection means, and a circuit consisting of an inverting circuit 6, a delay circuit 5, etc. The circuit constitutes the key press signal detection control means.

When the switch of the power supply circuit (not shown) is closed and the power supply voltage is applied to each circuit r, the change in potential generated in the inverting circuit 6r formed by a flip-flop is transferred from the AO terminal to the key press signal detection circuit 4r. After that, for example, a transistor in the circuit is operated to wait for a key to be pressed on the melody playing keyboard 1.

Corresponding to the first key press, a negative trigger is output from the terminal KP of the detection circuit 4 and applied to the delay circuit 5. A trigger pulse delayed by l pulse is obtained in the delay circuit 5r to invert the flip-flop of the inversion circuit 6, and the potential of the AO terminal to the key press signal detection circuit 4 is also inverted. (The one-pulse delay time described above is necessary to prevent unstable signal transmission to the storage circuit 2, which will be described later.) The inverting circuit 6r is required to send this signal from the rhythm pulse generator 10 every bar of the performance piece. Since a pulse signal is given, the potential of the AO terminal from the inversion circuit 6 is inverted again every time the pulse signal rises, and the operation described below can be performed by pressing the first melody performance key of each measure. . For example, if the first key pressed on the melody performance keyboard 1 is the note B, the transistor in the memory circuit 2 is activated, and only the output terminal of the memory circuit 2 corresponding to the key of the note B is set to zero. One bolt, and the other one at negative potential.

At this time, when two keys are pressed at the same time, it is convenient to configure the memory circuit 2 to give priority to the key or to continue the operation for the original key, and then performs that operation. The problem with the memory circuit is that the patent applicant has already
I am proposing this. (Refer to Japanese Patent Application Laid-open No. 71315/1983). The output of the memory circuit 2 is applied to the key selection circuit 3e.

The embodiment shown in FIG. 1 shows that the key selection circuit 3 can select from two types, C major and A minor, and the accompaniment chord can be specified by combining the selected key and the output from the memory circuit 2. A code gate 8 is configured. That is, when the key B is pressed and the output r of the memory circuit 2 is, if C major is selected in the general selection circuit 3e, the chord gate 8 is output.
selects the G chord, and if A minor is selected, the E chord is selected. The following table shows an example code table for this case. Therefore, if you preset the key selection circuit 3 to either C major or A minor for a performance piece 1 and press the melody keyboard 1, the same accompaniment tone as mentioned above will be played until the end of the measure. For the next bar, the chord note corresponding to the first key becomes the accompaniment note.

It is also possible to change the selection of the key selection circuit 3 midway through the content of the song. The above is an explanation of the operation based on the block diagram 1 in FIG. 1, but the specific circuit diagram in FIG.
The blocks shown in FIG.

In FIG. 2r, memory range 2 is the transistor Q2l, .
The transistor Q2O is a constant current source.
Purchased with R circuit and diode. Key press signal detection circuit 4
is composed of a transistor Q4l, a Zener diode, a resistor, a differential capacitor, and a diode. The delay circuit 5 is a transistor Q5 that constitutes a monostable multivibrator.
2 and the differential capacitor are the main parts. The inverting circuit 6 includes transistors Q6l and Q62, which form a flip-flop circuit.
and resistance is the main part. When the power supply voltage is applied in FIG. 2 t, the transistor Q62 of the inverting circuit 6 becomes ON. The collector of the transistor Q4l of the key press signal detection circuit 4 is 0FF at zero potential, but when any key on the keyboard 1 is pressed, the transistor Q4l becomes ON. At this time, the potential change resulting in the negative potential of the collector is differentiated, and a negative trigger pulse is generated. The negative trigger pulse drives the monostable multivibrator of the delay circuit 5 from the terminal KP, and after differentiation,
The transistor Q62 of the inverting circuit 9 is inverted so that the potential of the terminal AO is negative and the base of the transistor Q4l is negative. Therefore, even if the next melody keyboard is played in the same measure, the Q4lP0N does not occur and the above-mentioned operation does not occur. However, since the signal from the rhythm pulse circuit 10 inverts the transistor Q62 every bar, the transistor Q4l becomes active every bar. When the key e of note B is pressed, the base potential of transistor Q2ll changes from -20 to -6V, so Q2ll becomes 0N. Therefore, Q2l
2 also becomes 0N, and the potential of one input terminal of the 0R circuit G (5E) of the key selection circuit 3 becomes zero.Even if the key is released, R2, 1
, R2l2 and r maintain the ON state of Q2ll.
For example, when the keys B and A# are pressed, the current from the constant current source Q2O causes a potential drop through the diode D2l, and the emitter potential r of the transistors Q2ll and Q22l.
This is possible by giving this difference and setting only Q2ll to 0N. If the key selection circuit 3r selects the C major key, a negative potential is applied to the terminal e on that side, so that only the output of the 0R circuit G becomes negative, and a signal specifying the G chord is obtained. When selecting A minor, specify the E chord to give a negative potential to the terminal r on that side. The reset circuit 7r-
When a pulse signal ST as shown in FIG. Since the transistor Q7 is turned on and the collector of the transistor Q2O is pulled down to 0V, the memory circuit 2 is reset and the chord output is stopped.

Further, when the pulse signal ST is input to the inverting circuit 6r and the rhythm stops, the inverting circuit 6 outputs an inverting operation signal that puts the key press signal detection circuit 4 into the standby state. If the key selection circuit 3v is increased and the number of 0R circuits is increased, and q settings are made as shown in FIG. 3, it becomes possible to select other keys.

Therefore, according to the present invention, the rise of the pulse signal for each bar from the rhythm pulse generation circuit causes the key press signal detection circuit to enter the standby state. As shown in the figure, the detection circuit operates as soon as the first key depression signal r of the measure is received, and a predetermined accompaniment tone can be obtained.

That is, from the signal r from the rhythm pulse generator shown in FIG. 4B(1)(l), the key press signal detection circuit enters the standby state as shown in FIG. ) From the first key press signal of the measure shown, for example, the C key signal t, the same figure B
(4) The output shown here is the C chord accompaniment tone obtained when the C major key is selected.B (2) in the same figure shows the delay time τ of the delay circuit 5 (determined from the time constant 1 of the monostable multivibrator) from the C key signal. After the lapse of time, the C chord of the accompaniment does not change because the key press signal detection circuit does not enter the standby state when the F key or the E key is pressed. Then, when entering the next measure, the signal e from the key pressed after that, for example, the D key, will output G.
Change to code.

[Brief explanation of the drawing]

1 is a diagram showing an embodiment of the present invention from a block diagram; FIG. 2 is a specific circuit diagram of FIG. 1; FIG. 3 is a diagram showing another example of the configuration of the key selection circuit of FIG. 1; FIG. 4 is a diagram illustrating the operation of the present invention, FIG. 5A is a diagram showing pulses output by the rhythm pulse generation circuit 10, and FIG. 5B is a diagram showing the differential pulse thereof. 1..."・゜Key switch group interlocked with the melody keyboard, 2... Memory recall 3... key selection circuit, 4... key press signal detection circuit, 5...
Delay circuit 66...Inversion circuit, 8...Code gate, 9...Code sound source, 10...
...Rhythm pulse generation circuit.

Claims (1)

[Claims] 1. Store the note name of the key pressed on the melody keyboard in a memory circuit, output a code corresponding to the stored note name, and generate a gate corresponding to the code using a rhythm pulse from a rhythm pulse generation circuit. In the automatic rhythm accompaniment device, the automatic rhythm accompaniment device opens and closes the keyboard to generate an accompaniment sound according to a chord corresponding to the note name of the pressed key. key press signal detection means for storing the note name of the key corresponding to the pressed key in the memory circuit through a key detection operation; a key press signal detection control means for inputting a second pulse, outputting an operation signal in response to the input of the detection signal, and outputting an inverted operation signal in response to the input of the first pulse; The key signal detection means stops the key press detection operation and the storage operation in the memory circuit upon input of the operation signal from the key press signal detection control means, and stops the key press detection operation and the memory circuit upon input of the inversion operation signal. 1. An automatic rhythm accompaniment device characterized by starting a memorizing operation to detect the first key pressed in one bar, and storing the note name of the key pressed by the pressed key.