JPS5931078B2 - Automatic accompaniment device for electronic musical instruments - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides an automatic accompaniment device for an electronic musical instrument that controls the intensity of accompaniment sounds corresponding to rhythms such as chord chords and bass notes in response to key touches (key press strength). Regarding.

An electronic musical instrument is equipped with a sound source circuit that generates sound source signals corresponding to each tone pitch, and selects and derives the sound source signals from this sound source circuit in response to key operations, forms a tone as appropriate, and generates a musical sound signal. It is.

That is, the keyboard section is configured to perform performance operations corresponding to melodies, chord chords, etc., and furthermore, the pedal keyboard is used to play bass sounds. In this case, the keyboard section of the electronic musical instrument is divided into, for example, an upper and lower keyboard, and a pedal keyboard, and accompaniment sounds are usually played using the lower and pedal keyboards. A plurality of keys making up a chord chord are operated in accordance with the rhythm, and a pedal keyboard is used in which keys corresponding to a bass note are operated in accordance with the bass rhythm. However, for beginners, it is extremely difficult to play chord chords and bass accompaniment sounds on the lower keyboard and pedal keyboard in response to melody performances on the upper keyboard.
I am unable to fully enjoy playing an electronic musical instrument.

As a means to improve these drawbacks, for example, you can operate multiple keys that make up a chord chord on the lower keyboard, or one key that specifies a chord name, and create multiple sound sources that make up a chord chord corresponding to that operated key. It has been considered to incorporate an automatic accompaniment device that discriminately selects and derives the signal and the bass sound source signal, and opens and closes the output in response to rhythm pulses from a rhythm pulse generation circuit.

In other words, if you use such an automatic accompaniment device, you can automatically play accompaniment tones such as chord chords and bass notes by simply specifying chord names, etc., without having to play the rhythm of accompaniment tones on the keyboard. This allows even beginners to effectively enjoy playing electronic musical instruments. However, the accompaniment sounds obtained in this way are only generated in response to rhythm pulses, and their sound and volume levels are controlled, for example, as an overall volume using an expression mechanism, so that they do not match the musical idea. Therefore, the performer's intention cannot be expressed on the automatic accompaniment performance sound.

This invention was made in view of the above points, and is an automatic accompaniment for electronic musical instruments that effectively expresses the performer's intention in the accompaniment performance sound and allows the user to easily enjoy more advanced electronic musical instrument performances. The device is designed to detect and store the intensity of key presses on a keyboard section that specifies accompaniment sounds, and to control the opening/closing signal level using a rhythm pulse signal that opens and closes the sound source of the accompaniment sounds in accordance with the stored value. This is what I did. An embodiment of the present invention will be described below with reference to the drawings. 1st
The figure shows its configuration. Reference numeral 11 is a key switch circuit provided corresponding to each key of the lower hand keyboard for performing accompaniment tone performance, for example, and a movable switch circuit 11 is provided corresponding to each key of the lower hand keyboard for performing accompaniment sounds. It is equipped with a key switch 12 which is driven to switch between two halves. Then, the fixed terminal a on the normally closed side of this key switch 12
A "+V" power supply is connected to the terminal, and the key press signal is taken out from the normally open fixed terminal b, and the movable terminal c is grounded through a parallel circuit of resistor R1 and capacitor C1. Become. That is, in a steady state when the key is not operated, the key switch 12 is in the state shown in the figure, and the capacitor C1 is set to be charged at "+V".

When the corresponding key is operated and the movable contact piece C of the key switch 12 separates from the fixed terminal a, the charging circuit for the capacitor C1 is cut off, and the charge in the capacitor C1 is discharged via the resistor R1. become. That is,
The terminal potential of capacitor C1 is the capacitor C1 and resistor R.
The discharge is reduced with a time constant determined by a value of 1. Then, when the key is pressed further and the movable contact piece C of the key switch 12 comes into contact with the fixed terminal b, the terminal potential of the capacitor C1 at that time is read out from the fixed terminal b as a key press signal. The key press signal read out in response to the key operation in this way is transmitted from the movable contact piece C of the key switch 12 to the fixed terminal a.
It becomes inversely proportional to the time required to switch from to b, and if this movable contact piece C is driven as the corresponding key descends, the key depression signal is the descending speed of the key, that is, It is expressed as a signal proportional to the key press strength.

That is, this key switch circuit 11 is configured to be touch-sensitive, and a key press signal corresponding to the key press strength is sent to the first switch 13 and the second switch 14, which are input reciprocally. lead The signal taken out from the first switch 13 is supplied to the base of the transistor Tr constituting the envelope circuit 15. Further, the signal taken out via the second switch 14 is passed through the memory circuit 18 through a gate circuit 17 that is gate-controlled by a differential pulse from a differential circuit 16 that detects the rising edge of the key press signal.
It comes to be stored as the charging potential of the capacitor C2 constituting the capacitor C2. According to the storage potential in the storage circuit 18, the rhythm pulse signal is supplied to the VCAl9.
It controls the amplification gain of a voltage-controlled variable gain amplifier (voltage-controlled variable gain amplifier), and the output rhythm pulse signal from this VCAl9 is supplied to the base of the transistor Tr of the envelope circuit 15. The transistor Tr supplies +V power to its collector, and its emitter is resistor R2.
and capacitor C3 are connected in parallel to ground.
A switching signal output for switching the sound source signal is obtained from the emitter circuit.

That is, while the base circuit of the transistor Tr is supplied with a signal associated with a key press, the collector and emitter of the transistor Tr are in a conductive state, charging the capacitor C3 with "+V" and outputting an opening/closing signal due to "+V". After the signal falls due to key depression, resistor R2 and capacitor C
With a time constant determined by a value of 3, the opening/closing signal depicts an attenuation envelope. That is, the state in which the first switch 13 is turned on and the second switch 14 is opened sets the normal performance state, and when a key is operated, a key press signal corresponding to the key press strength is sent to the key switch. is taken out from the circuit 11 and sent to the envelope circuit 1 via the first switch 13.
5.

The envelope circuit 12 generates an opening/closing signal at a level corresponding to the key depression strength, controls the opening/closing circuit to which the sound source signal corresponding to the pitch of the operated key is coupled, and controls the key depression strength. Derive a sound source signal with a level corresponding to
Begins to form performance sounds. In other words, when a key is operated, the performance sound corresponding to the pitch of the operated key is controlled to be produced at a level corresponding to the strength of the operated key.
Ordinary electronic musical instrument performances can now be expressed using Tatsuchi Sensitive. In addition, as shown in the figure, the first switch 13
When the second switch 14 is turned on instead, the key press signal corresponding to the key press strength is stored and held in the memory circuit 18 without the key press signal being supplied to the envelope circuit 15 due to the key operation. . That is, the amplification gain of the VCAl9 is set in proportion to the key press strength, and the rhythm pulse is extracted at a level proportional to the key press strength, thereby controlling the base of the transistor Tr of the envelope circuit 15. That is, this envelope circuit 15
A rhythmic pulse-like opening/closing signal with a level proportional to the key pressing strength is extracted from the key press.If this opening/closing signal is used to control opening/closing of the sound source signal of the chord chord corresponding to the operating key, for example, the key Automatic accompaniment performance sound accompanied by a rhythm whose volume etc. are set by touching can be obtained. In this embodiment, in order to control the rhythm pulse opening/closing signal level, a VCAl9 is inserted into the rhythm pulse input circuit of the envelope circuit 15, and this VCAl9 is controlled by the key press strength. If the circuit corresponding to the first switch 13 is omitted, the VCAl9 controlled by the memory circuit 18 may be inserted on the output side of the envelope circuit 19 as shown in FIG. In this case, the rhythm pulse is directly supplied to the base circuit of the transistor Tr. In addition, the same effect can be obtained by arbitrarily inserting and setting the VCA at a point where the amplification gain of the transistor Tr can be controlled. Fig. 3 shows an example of a means for obtaining chord chords and bass notes in the automatic accompaniment device as described above, in which C, C+, etc. corresponding to each key operation on the keyboard section are shown. ...A key ink signal is input to the input terminal section of B.

For example, if you want to obtain the accompaniment sound for a C chord chord, you would operate the three keys on the keyboard that correspond to the chord C, C, E, and C. logic"
1'' key ink signal is coupled thereto, and this key ink signal is appropriately generated in conjunction with the key switch circuit.
The key ink input terminals of C, C+, . . . B are connected to C, C+, .
... is led to the output terminal of B and is supplied to the envelope circuit of the corresponding pitch. Further, the key ink input signal is supplied to a root note detection circuit 20, which determines a chord name from the combination of note names of the input key ink signal and generates a root note signal output corresponding to the chord name. .

For example, as mentioned above, when there are key ink signal inputs of C, E, and G, the chord name C is determined and the output of the root note C is obtained.
It is supplied to a group of AND circuits that obtains bass pitch signals of pitches of degrees and fifths. And the above chord chord and 1st, 5th
The AND circuit for the bass tone of the degree is used for chord accompaniment from the rhythm pulse forming circuit 21, for the bass 1st, and for the bass 5th.
Gate control is performed using rhythm pulses for frequency, and rhythm pulse distribution control is performed for generating chord and bass sounds.

That is, the chordo tone rhythm pulse from the rhythm pulse distribution circuit shown in FIG. 3 is supplied to the envelope circuit 15 shown in FIG. By supplying the signal to the gate, automatic accompaniment performance accompanied by rhythms such as chord chords and bass notes can be performed.

Note that, by changing the rhythm pulse distribution control means, automatic accompaniment performance of not only chord chords and bass notes but also arpeggios and arpeggios can be executed.

As described above, according to the present invention, the volume of the automatic accompaniment sound is controlled by the performer, and the accompaniment sound can be arbitrarily set according to the idea of the song, such as a melody. Even beginners can easily improve the performance expressiveness of electronic musical instruments, which has a very large effect on improving the functions of electronic musical instruments.

[Brief explanation of drawings]

FIG. 1 is a diagram illustrating an automatic accompaniment control means according to an embodiment of the present invention, FIG. 2 is a diagram illustrating a partially modified means of the above embodiment, and FIG. 3 is a diagram used in combination with the above control means. It is a figure which shows the example of a rhythm pulse distribution means with respect to each pitch.

Claims (1)

[Claims] 1 A keyboard section for specifying accompaniment tones such as chord chords, a key press strength detection circuit that detects the key pressing force when operating keys on this keyboard section, and a memory circuit that stores detection signals from this key press strength detection circuit. and a means for variably controlling the level of the opening/closing signal corresponding to the rhythm pulse according to the stored value of the memory circuit, so that the accompaniment sound specified to be played on the keyboard section corresponds to the opening/closing signal whose level is controlled. An automatic accompaniment device for an electronic musical instrument, characterized in that the automatic accompaniment device derives the accompaniment performance sound by deriving the accompaniment performance sound.