JPH0313594B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an electronic musical instrument in which the characteristics of an output musical instrument can be varied by using an operator.

[Prior art]

Conventionally, music synthesizers convert the output from operators such as pitch benders and modulation wheels into analog to digital form, and control various operations of electronic musical instruments based on the converted output. .

In this case, since the operability of the electronic musical instrument is particularly important for the operator, the wiring becomes long, and external noise is likely to be added to the conversion output. Therefore, as a conventional method to prevent this, a certain threshold value is set and the data obtained from the A/D converter is
When the data obtained this time does not exceed the threshold value by comparing it with the previously obtained data for changing the characteristics of the musical instrument, the data is considered to have not changed.

[Problems with conventional technology]

In the conventional device described above, the data obtained from the A/D converter becomes a series of data that is continuous like stepping stones and has an interval of a set threshold value, which is an undesirable problem.

For example, if the data after the previous A/D conversion is "0110" and the threshold value is 2, if the voltage value at the A/D converter input terminal changes in an increasing direction,
The data is not considered to have changed until the data after A/D conversion becomes 0110+3 ₍₁₀₎ , that is, "1001". Similarly, the next data obtained is 1001+3 ₍₁₀₎ , or "1101".

In other words, in a system in which the 4-bit A/D converter described above is set with a threshold of 2 for noise removal, only a series of consecutive data with intervals of 3 can be obtained. become. Therefore, there is a problem in that smooth changes in frequency are not required.

[Purpose of the invention]

This invention was made in view of the above-mentioned circumstances, and its purpose is to make it less susceptible to noise and to smoothly change the degree of modulation of pitch and vibrato in accordance with changes in the controls. The purpose is to provide electronic musical instruments that are

[Summary of the Invention] The present invention provides a calculation means for calculating the average value of digital data corresponding to the operation of a controller and data used to vary the characteristics of the previous musical tone, and a calculation result of the calculation means. A storage means for storing the data, a control means for varying the characteristics of musical tones based on the storage result of the storage means, and a control means for comparing the digital data corresponding to the operation of the operator with the calculation data stored in the storage means, By providing a comparison judgment means that stops the operation of the calculation means when the difference value of data is within a predetermined value, and causes the operation of the calculation means to be executed when the difference value exceeds the predetermined value,
When the change in the digital data in response to the operation of the controller is less than a predetermined value, the calculated data used to control the musical tone characteristics is used again, and conversely, when the change is greater than the predetermined value, this digital data is combined with the previous calculated data. The average value is used as new calculation data to control musical tone characteristics.

〔Example〕

Hereinafter, one embodiment of the present invention will be described with reference to the drawings. In FIG. 1, a keyboard 1 has, for example, 61 keys ranging in pitch from C ₁ to C ₆ . The signals from each key are then sent to the CPU (Central Processing Unit) 2 for processing, and the key code is output to the pitch information creation section 3, and the on/off signals for each key are output to the tone creation section 4. Ru.

The CPU 2 is comprised of a microprocessor etc. that controls all operations of this electronic musical instrument, and also receives various switch outputs from the switch section 5 and provides various musical tone generation information to the pitch information generation section 3 and the musical tone generation section 4.

In addition, 6 in the figure is a pitch bender, the output of which is detected by the pitch bend detector 7,
After the D conversion, an average value calculation operation, etc., which will be described later, is executed, and the resultant data is provided to the pitch information creation section 3 as corresponding pitch bend data. Then, the pitch information creation section 3 multiplies the pitch bend data by ΔPITCH (minor pitch) per 1 bit of pitch bend data, and adds a scale code corresponding to the key code from the CPU 2 to the resulting data. Then, the result is given to the tone creating section 4 as pitch data.

The musical tone creation section 4 uses the pitch data and the CPU 2.
Creates a musical tone signal based on musical tone creation information such as key on, off signals, other tones, rhythms, etc.
It outputs it to the D/A converter 8. The musical tone signal inputted to the D/A converter 8 is converted into an analog musical tone signal, and is emitted as a musical tone via an amplifier 9 and a speaker 10.

FIG. 2 shows a specific configuration of the pitch bend detection section 7. As shown in FIG. The output of the pitch bender 6 is converted into digital data IN by an A/D converter 11, and is provided to a data converter 12. This data converter 12 inputs the data IN and the previous calculation result data of the data converter 12, averages them, and obtains the current calculation result data (also called data V; 8-bit data), Give it to exclusive or gates 13 ₇ to 13 ₀ . The other end of the exclusive OR gate ₁₃₇ to which the most significant pit data of the data V is input is always supplied with a "1" signal.
Further, the other terminals of the other exclusive OR gates 13 ₆ to 13 ₀ are always supplied with a "0" signal. That is,
Exclusive OR gates 13 ₇ to 13 ₀ serve as inverting circuits for only MSB data, and each exclusive OR gate 13
The outputs of ₇ to 13 ₀ (also referred to as data A) are input to one end of each of the corresponding exclusive OR gates 14 ₇ to 14 ₀ . The MSB of the data V is supplied to the other ends of the exclusive OR gates 14 ₇ to 14 ₀ via a data inverter INV. The outputs of the exclusive OR gates 14 ₇ to 14 ₁ are then output as pitch bend data B.

FIG. 3 shows a specific configuration of the data conversion section 12. Data IN is adder 15 and comparator COMP
Enter at one end of. The data V from the buffer 17 is input to this adder 15, and therefore both data IN and V are added, resulting in data (IN+
V) is given to the 1/2 arithmetic unit 16 and (IN+V)/
2 is calculated and given to buffer 17. Therefore, the data V is the average of the current data IN and the previous result data V. This result data V is also input to the other end of the comparison unit COMP. This comparison unit COMP compares the data IN and data V, and when |IN−V|>3 (this data 3 indicates a threshold value), generates a “1” level signal S and adds it. 15.

The adder 15 executes the addition operation only when the signal S of "1" is input, and does not execute the addition operation when the signal S of "0" is input. Therefore, during this non-addition, the output data V of the buffer 17 is the same as the previous time and remains unchanged.

FIG. 4 shows a specific configuration of the pitch information creation section 3. In the figure, a ROM (read only memory) 18 stores a plurality of data γ' ₁₆ indicating the ΔPITCH in semitone units, and a pitch bender 6 controls the pitch maximum change by a semitone by a predetermined switch of the switch unit 5. When specified in units, the CPU 2 is addressed by the address section 19 according to the data correspondingly outputted to the address section 19, whereby any data γ' ₁₆ is read out and applied to the multiplication section 20. Pitch bend data B is also input to this multiplier 20, and the resultant data γ' ₁₆ ×B multiplied by both data γ' ₁₆ and B is given to an adder 21. A scale code corresponding to the key code from the CPU 2 is input to the adder 21, and the two are added together and sent to the tone generator 4 as pitch data. This pitch data then becomes pitch frequency information proportional to cents.

Next, the operation will be explained with reference to FIGS. 5 to 11. Figure 5 shows the pitch information creation section 3.
The configuration of pitch data output by the adder 21 in the figure is shown. This pitch data consists of a total of 14 bits, of which the lower 6 bits represent a ΔPITCH portion indicating a pitch of less than a semitone, and the upper 8 bits represent a scale code. Figure 6 shows this scale code for each pitch from C ₁ to C ₆ .
Represented by hexadecimal code representation. Further, FIGS. 7 and 8 are diagrams for explaining the ΔPITCH.

That is, in FIG. 7, α exemplifies "00000001" representing semitone data as the maximum change in pitch caused by the pitch bender 6. Further, β exemplifies the maximum variable range of pitch bender "01111111". Therefore, the MSB "0" is a sign bit. Further, γ is an example of the result of calculating ΔPITCH per pitch bend bit by dividing the data of α by the data of β, and has the value shown in the figure. That is, if this value is expressed in hexadecimal code, γ ₁₆ =00.0204081. Then, when rounding at the position shown, the data when the maximum change in pitch is a semitone is γ′ ₁₆
becomes 00.020.

Figure 8 shows the method explained in Figure 7.
γ ₁₆ and γ′ ₁₆ are calculated and illustrated when the maximum change in pitch is from twice to 12 semitones, respectively.
Therefore, γ′ ₁₆ of the 13 types of semitone units shown in Figure 8 is
It is preset in the ROM 18, and the designation of γ' ₁₆ is performed by operating a predetermined switch in the switch section 5.

Therefore, if you set the predetermined switch to the desired position, for example, so that the maximum change in pitch is three times the semitone before starting the performance, the CPU
2, and provides the address section 19 with data for reading γ' ₁₆ for three times a semitone.
Allows ROM18 to be addressed. Therefore, from now on, ΔPITCH of "00.061" is read from the ROM 18 as γ' ₁₆ from FIG.
When the pitch bender 6 is changed from its minimum pitch position to its maximum pitch position, the pitch of the generated musical tone changes by a maximum of one and a half notes.

As described above, after setting the predetermined switches, the player operates the keys on the keyboard 1 and operates the pitch bender 6 as necessary to play the song.
In that case, the output of the key is input to the CPU 2 to create a key code and key on/off signals,
The key code is given to the pitch information creation section 3, and key on/off signals are given to the tone creation section 4. The musical tone generating section 4 is also supplied with other musical tone generation information such as rhythm and timbre from the switch section 5.

On the other hand, in the pitch bend detection section 7, the output of the pitch bender is sent to the A/D converter at a predetermined sampling period.
The data is A/D converted by the converter 11 and is provided to the data converter 12 as data IN. In the data converter 12, the data IN and the data V, which is the result of the previous calculation, are input to the comparator COMP, and it is determined whether |IN-V|>3.
Then, when |IN-V|
The signal is output from and applied to the adder 15.

Therefore, when the signal S is "0", the adder 15 does not perform the addition operation of the data IN and the data V;
Therefore, the data V output from the buffer 17 this time is the same as the previous time, in other words, the change in pitch is smaller than the predetermined threshold value "3" and it is considered that there is no change in pitch. become.

On the other hand, when the signal S is output as "1", the adder 15 adds the data V and the data IN (that is, it is assumed that there is a change in pitch between the previous time and this time), and the addition result ( IN＋
V) is then averaged by the 1/2 calculator 16 to obtain (IN
+V)/2, and is applied to the buffer 17 to become data V. Therefore, this data V is added to adder 1.
5 and the comparator COMP to be prepared for calculation in the next sampling period, and is also sent to the exclusive OR gates 13 ₇ to 13 ₁ .

The exclusive OR gates 13 ₇ -13 ₁ invert only the MSB of the data V and provide the data A to the exclusive OR gates 14 ₇ -14 ₀ . Therefore, this data A
is output from the exclusive OR gates ₁₄₇ to ₁₄₀ as data B, which is the same as all bit data A, when the MSB of the data V is "1", and when the MSB of the data V is "0", All bit data A is inverted and output as data B, which is used as pitch bend data.

FIG. 9 explains the operation of this pitch bend detection section 7, and shows the relationship between data V, A, and B. As shown in the figure, the pitch bend data B is set to the midpoint "00" when the data V is "7F" and "80", and when the data V is "7F"
→ In the direction in which the data V decreases to "00", it increases in the negative direction, that is, the actual pitch change becomes small.On the other hand, in the direction in which the data V increases from "80" to "FF", it increases in the positive direction, that is,
The actual pitch change becomes larger. Therefore, the content of the pitch bend data B changes depending on the actual operation of the pitch bender 6.

Further, in the pitch information creation section 3, the multiplication section 20
The pitch bend data B is input to ROM1.
γ′ ₁₆ from 8, that is, the maximum change in pitch in this case, is multiplied by the data “00.061” for one and a half notes and given to the adder 21, and the adder 21 further combines the multiplication result and the operating key. and a scale code corresponding to the key code, and provide actual pitch data to the musical tone creation section 4. Therefore, the musical tone creating section 4 creates a pitch musical tone signal based on this pitch data, and sends it to the D/A converter 8, amplifier 9, and speaker 10.
The sound is emitted as a musical tone through the .

FIG. 10 is a diagram for explaining the effect of the average calculation of the data conversion section 12. In other words, although the pitch bender 6 is fixed at a fixed position, a linearity error occurs in the output data IN of the A/D converter 11 due to external noise or the like. Here, the previous data V is assumed to be "99".
Among the consecutive sampling points A to J, points A and B
In this case, the value of data IN is "99", "100" at points C, E, H, and I, "98" at D, "101" at F, G, J
It says "97". However, in the data conversion unit 12, the relational expression |IN−
When V|>3, the change in the output data IN is recognized and the average is taken
(in this case, the value below the decimal point is rounded down) is always the value "99", and the output of the A/D converter 11 is corrected.

FIG. 11 is also a diagram illustrating the effect of the average calculation of the data converter 12, and in this case is an example in which the pitch bender 6 is suddenly changed. The solid line in the figure shows the change curve of the data IN according to the actual movement of the pitch bender 6, and the dashed line shows the change curve of the data V. Here, when changing from time t ₀ to t ₁ and from t ₁ to t ₂ , the current data IN has changed beyond the threshold, and after t ₂ , the current data IN remains unchanged. do. As can be seen from the drawing, the current data IN is always compared with the previous calculation result between each adjacent sampling point, and when the threshold value is exceeded, the current data IN is compared with the previous calculation result.
Since IN and the previous calculation result are averaged and used as the correction data V for the current sampling point, A/
Even if the sampling period of the D converter 11 is long, the data V has a smooth value against sudden changes in the data IN, and the rate of including errors such as external noise is extremely small.

Although the above-mentioned embodiment has been explained using a pitch bender as an example, the present invention may also be applied to the degree of modulation of vibrato by a modulation wheel, volume, etc.

[Effects of the Invention] As explained above, the present invention compares the digital data corresponding to the operation of the controller with the calculation data used for controlling the musical tone characteristics last time, and if the difference value is smaller than a predetermined value, the digital data corresponding to the operation of the controller is compared with the calculation data used for controlling the musical tone characteristics last time. Since the musical tone characteristics are controlled by using the noise again, meaningless fluctuations in the musical tone characteristics due to external noise are eliminated.

Furthermore, in the present invention, when the above-mentioned difference value is larger than a predetermined value, the average value of the digital data from the controller and the previously calculated data is calculated, and this new calculated data is used to control the musical tone characteristics. Therefore, even when the operator is suddenly changed, the calculated data changes smoothly, and the musical tone characteristics controlled thereby also change smoothly, which has the advantage of preventing the generation of unnatural musical sounds.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an electronic musical instrument according to an embodiment of the present invention, FIG. 2 is a specific block diagram of the pitch bend detection section 7, FIG. 3 is a specific block diagram of the data conversion section 12,
FIG. 4 is a specific configuration diagram of the pitch information creation section 3, FIG. 5 is a configuration diagram of pitch data, FIG. 6 is a diagram showing a scale code, and FIG. 7 is a diagram showing examples of various data for obtaining ΔPITCH. , FIG. 8 is a diagram showing the contents of data γ ₁₆ and γ′ ₁₆ for 12 types of pitch maximum changes, FIG. 9 is a diagram showing the correspondence with data V, A, and B in pitch bend detection section 7, and FIG. The figure shows how the data IN changes due to external noise when the pitch bender 6 is stopped, and FIG. 11 shows the relationship between the data IN and V when the pitch bender 6 is operated. be. 1... Keyboard, 2... CPU, 3... Pitch information creation section, 4... Musical tone creation section, 5... Switch section,
6...Pitch bender, 7...Pitch bend detection section, 8...D/A converter, 9...Amplifier, 10...
... Speaker, 15 ... Adder, 16 ... 1/2 arithmetic unit, COMP ... Comparison section, 18 ... ROM, 19 ...
. . . address section, 20 . . . multiplication section, 21 . . . addition section.

Claims (1)

[Scope of Claims] 1. An electronic musical instrument that includes an operator and changes the characteristics of an output musical tone according to the operating state of the operator, comprising: digital data generating means that generates digital data in accordance with the operation of the operator; , a storage means capable of storing digital data; and an arithmetic means for calculating an average value of the digital data from the storage means and the digital data from the digital data generation means, and storing the result of the calculation in the storage means. , Compare the digital data from the digital data generating means and the calculated data stored in the storage means, and if it is determined that the difference value between both data is within a predetermined value, stop the operation of the calculation means, and calculate the difference between the two data. Comparison and judgment means for executing the operation of the calculation means when it is determined that the value exceeds a predetermined value, and control means for varying the characteristics of the musical tone according to the calculation data from the storage means. An electronic musical instrument.