JPS5917435B2 - electronic musical instruments - Google Patents

Description

[Detailed Description of the Invention] This invention generates a fundamental wave (fundamental tone) and its harmonic components (overtones) corresponding to the pitch of an operating key, and generates amplitude coefficients corresponding to the fundamental wave and harmonic components, respectively. Regarding the improvement of harmonic synthesis electronic musical instruments that form musical tones by multiplying and adding the multiplied values, this issue occurs particularly in relation to key touches such as key pressing speed, key pressing pressure, key pressing depth, etc. The present invention relates to an electronic musical instrument in which the timbre of musical tones can be variably controlled.

A. Description of the prior art As an electronic musical instrument using harmonic synthesis method, the amplitude value at consecutive sample points of a musical sound waveform is
) formula, there is also one in which musical tones are obtained by sequentially calculating 10 to .

2｜76XO(qR)■n怀nSinwnqR・・・・・・
・・・(1)(q=1,2, ・ ・ ・ ・ ・ ・
・ ・ ・ )Here, Xo(qR)・・・・・・・・・
・Waveform amplitude value at each sample point of the musical sound waveform.

R: A numerical value proportional to the frequency (pitch) of a generated musical tone (hereinafter referred to as a frequency number).

n ・・・・・・Represents the order of harmonic components including the fundamental wave, n=1 is the fundamental wave (fundamental tone), 75n■2 is the second
Harmonic (2nd harmonic), n-3 is 3rd harmonic (3rd harmonic)
Corresponds to...

Cn......Amplitude coefficient (Fourier coefficient) for harmonic components of each order.

10N・・・・・・Number of sample points of musical sound waveform.

w: Number of harmonics (overtones) included in amplitude calculation at each sample point. There is a relationship of W=N/2.

An electronic musical instrument based on this harmonic synthesis method is configured as shown in, for example, 5 in FIG.

In the figure, reference numeral 1 denotes a key switch circuit provided in the keyboard section, which has a key switch corresponding to each key on the keyboard section. When a certain key is pressed, the corresponding key switch operates, and its output is It is configured to output a signal of logic value "1" to the line. This key switch circuit 1 has a built-in single-tone priority circuit, and when two or more key switches operate at the same time, the S1'' signal is output only to the output line corresponding to the key switch with a higher priority. The output line corresponding to each key switch of the key switch circuit 1 is connected to the input side of a frequency number memory 2 in which a frequency number R corresponding to the pitch of each key is stored, and when a certain key is pressed, is addressed by the output of the key switch circuit 1, and the frequency number R corresponding to the pitch of that key is read out from the frequency number memory 2. On the other hand, the clock oscillator 4 outputs a clock pulse Tc of a constant period; The clock pulse Tc is frequency-divided by w in the counter 4 to become a calculation interval timing signal Tx.

In this case, "W" is the total number of harmonics to be synthesized; for example, when synthesizing up to the 16th harmonic, "W-1
6". Note that the term "harmonic" in the following description includes the fundamental wave, and the fundamental wave (fundamental tone) corresponds to the first harmonic. The calculation interval timing signal Tx generated in this way is supplied to the gate 5. This gate 5 opens the gate every time the calculation interval timing signal Tx is supplied (and supplies the frequency number R output from the frequency number memory 2 to the interval interval adder 6.
Every time the frequency number R is supplied via the gate 5 (that is, every time the calculation interval timing signal Tx is generated), the frequency number R is accumulated and the result is 1R12R13R...
. . . and outputs the cumulative value QR that increases the power n. and,
When the accumulated value QR exceeds the modulus N of the adder 6, it overflows and becomes all zero, and thereafter, the same accumulation operation is performed again every time the calculation interval timing signal Tx is generated. In this way, the calculation interval timing signal T
The cumulative value QR that changes every time x occurs is determined by the clock pulse T.
It is fed to a harmonic section adder 8 via a gate 7 gated by c. In this case, the clock pulse T
Since c has a frequency w times the calculation interval timing signal TXf), the gate 7 is opened w times during one period of the calculation interval timing signal Tx. As a result, the harmonic section adder 8 sequentially adds the cumulative value QR output from the gate 7 every time the clock pulse Tc occurs, and outputs the cumulative value NqR. Then, when the accumulation W times is completed, it is reset by the calculation interval timing signal Tx,
The same operation will be performed thereafter. Therefore, the harmonic section adder 8 calculates the accumulated value Nq which increases sequentially in accordance with the clock pulse Tc during one cycle of the calculation section timing signal Tx.
This means that R (n=1, 2, 3...) is generated. This accumulated value NqR is decoded by the memory address decoder 9 (), and this decoded output is addressed to the sine function memory 10 which stores the amplitude value of each sample point of one period of the sine wave waveform at each address. a sine amplitude value πSin supplied as a signal from said memory 10;
Read NqR.

As is clear from the above explanation, the cumulative value QR of the pitch interval adder 6 indicates the sample point at which the musical waveform amplitude is to be calculated, and the cumulative value NqR of the harmonic interval adder 8 indicates the sample point at which the musical waveform amplitude is to be calculated. It represents the phase of the n-th harmonic at the sample point QR.

As a result, from the sine function memory 10, the sample point QR
The sine amplitude value 81n of each harmonic (including the fundamental wave) in
-N, R (n-1, 2...W) is the fundamental wave 1λ1 (first harmonic), second harmonic,...
- Generated sequentially in the order of the w-th harmonic.

In this case, the sequential sample points of the musical sound waveform to be calculated shift sequentially every time the calculation interval timing signal Tx is generated, but which sample point to shift to next is determined by the frequency number R. This frequency number R is proportional to the pitch of the operating key. Therefore, the sine function meseri 10 sequentially generates sine amplitude values (Sin-NqR) 1X1 of each harmonic corresponding to the pitch π of the operating key in a time-division manner.

On the other hand, the memory address control device 11 is modulo W.
The clock pulse Tc is sequentially counted in synchronization with the counter 4, and the count value is outputted to the harmonic coefficient memory 12 as an address signal.

The harmonic coefficient memory 12 stores a harmonic amplitude coefficient C corresponding to the optimum amplitude value of each harmonic in order to obtain a desired musical timbre.
n is stored in each address, and when an address signal that counts up in synchronization with the clock pulse Tc is supplied from the memory address control device 11, a harmonic that sets the amplitude value of each harmonic stored in each address is supplied. The wave amplitude coefficients Cn are sequentially read out. This harmonic amplitude coefficient Cn is output to the harmonic amplitude multiplier 13. The harmonic amplitude multiplier 13 calculates the sine amplitude value lSin-NqR of each harmonic read out from the sine function memory 10 in a time-sharing manner for each sample point and the harmonic amplitude 1X set for each harmonic.
7 width coefficient Cn and the multiplied value Fn=π Cnsin is supplied to the accumulator 14.

In this case, since the harmonic section adder 8 and the memory address control device 11 are synchronized with each other, the harmonic amplitude coefficient Cn sequentially read out for each harmonic is multiplied by the harmonic sine amplitude value Sin-NqR corresponding to π. (1X1) Accordingly, the amplitude value Fn for each harmonic is set.

The accumulator 14 sequentially accumulates the amplitude value Fn of each harmonic output from the harmonic amplitude multiplier 13. When the calculation interval timing signal temporary is generated, the gate 15 opens and the accumulated value of the accumulator 14 (representing the amplitude value at a certain sample point of the musical waveform) is output to the D-A converter 16. At the same time, the accumulator 14 is reset and the same accumulation operation as described above is performed again in order to calculate the amplitude value at the next sequential sample point. Therefore, the D-A converter 16 calculates the cumulative value of the set amplitude values of each harmonic at each sample point of the musical sound waveform corresponding to the pitch of the pressed key every time the calculation interval timing signal Tx is generated. This accumulated value is converted into an analog signal and sent to the sound system 1.
7, a musical tone with a pitch corresponding to the pressed key and a tone corresponding to the harmonic amplitude coefficient Cn which sets the amplitude ratio of each harmonic stored in the harmonic coefficient memo 1 and 2 is generated. . Furthermore, this electronic musical instrument is provided with a touch detection circuit 18 that detects key touch conditions such as key press speed, pressure, and depth associated with key press operations.

This touch detection circuit 18 has a key touch detection sensor such as a coil that detects the key press speed of each key or a piezoelectric element that detects the key press pressure of each key, and the output of this key touch detection sensor is It is output as a touch signal T to the sound system 17. In this case, the touch signal T output from the touch detection circuit 18 and the output signal sent from the key switch circuit 1 correspond to the same operation key. The sound system 18 controls the amplitude of the generated musical tones in response to the touch signal T, so that the volume of the generated musical tones can be controlled by touching a key, similar to a natural musical instrument such as a piano. On the other hand, an amplitude envelope is assigned to a generated musical tone in the following manner.

That is, the sound system 17 is provided with an envelope waveform generator that starts operating in response to a key-on signal KON output from the key switch circuit 1 when any key is pressed. The musical tone signal is multiplied by the envelope waveform output from the musical tone signal, and amplitude envelopes such as attack, sustain, and decay are imparted to the generated musical tone. Incidentally, since such an electronic musical instrument is disclosed in Japanese Patent Application Laid-open No. 4890217, detailed explanation thereof will be omitted.

B. Disadvantages of the Prior Art As is clear from the above explanation, the conventional harmonic synthesis method electronic musical instrument described above uses a frequency corresponding to the pitch of the pressed key and a harmonic amplitude coefficient stored in the harmonic coefficient memory. A musical tone is generated with a timbre set by Cn and a volume corresponding to the amplitude envelope and key touch.

Therefore, the volume of this generating instrument is controlled in response to key touches, and the amplitude envelope is controlled in response to key presses and key releases, and the tone color of the musical tone does not change at all. However, in general, the sound produced by a natural musical instrument not only changes in volume but also in timbre (waveform shape) subtly depending on the state of the sounding operation (for example, key pressing), and this causes the naturalness to change slightly. It has a rich sound. However, the above-mentioned conventional harmonic synthesis type electronic musical instruments have the disadvantage that the timbre cannot be controlled by key press operations as in natural musical instruments, and the generated musical tones are extremely monotonous.

C. OBJECTS AND SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned drawbacks of the conventional art, and its purpose is to produce musical sounds generated in connection with key touches accompanying key press operations in harmonic synthesis type electronic musical instruments. The goal is to make it possible to change the tone of the sound.

For this reason, in the present invention, each amplitude coefficient for setting the amplitude value of each harmonic wave constituting a musical tone is relatively variably controlled by a key touch signal. Hereinafter, the electronic musical instrument according to the present invention will be explained in detail using the drawings.

D. DESCRIPTION OF CONFIGURATION AND OPERATION OF THE INVENTION 1 Explanation of the Structure of the Invention FIG. 2 is a block diagram showing an embodiment of the electronic musical instrument according to the present invention, and the same parts as in FIG. 1 are designated by the same symbols.

In the figure, 19 is a harmonic coefficient addressed by the harmonic order signal n outputted from the memory address control device 11 and the digital touch signal TD outputted from the touch detection circuit 18, and the harmonic amplitude coefficient CnT is read out. The harmonic coefficient memory 19 is a memory, and is composed of a plurality of groups of memories in which harmonic amplitude coefficients Cn corresponding to each harmonic order are stored differently, for example, and the harmonic coefficient memory 19 is composed of a plurality of groups of memories in which different harmonic amplitude coefficients Cn corresponding to each harmonic order are stored. The harmonic order is specified by the touch signal TD, the group is specified by the touch signal TD, and the corresponding harmonic amplitude coefficient CnT is read out. 2. Description of the operation of this embodiment In the electronic musical instrument configured as described above, when a key on the keyboard section is pressed, the corresponding key switch closes and the corresponding output line of the key switch circuit 1 is connected to S1''. A signal is output.

In this case, since the key switch circuit 1 has a built-in single note priority circuit, even if multiple keys are pressed, the S1'' signal is output to only one output line with a high priority. The output signal is the frequency number memo IJ2
Address the frequency number R corresponding to the pitch of the pressed key.
Read and output. This frequency number R is determined by the constant cycle clock pulse T output from the clock oscillator 3.
The signal is supplied to the pitch section adder 6 via the gate 5, which is opened by the calculation section timing signal Tx, which is generated by dividing the frequency c by .degree. C. into the frequency w. The pitch interval adder 6 sequentially adds the frequency numbers R supplied each time the calculation interval timing signal Tx is generated, and outputs a cumulative value QR. This accumulated value QR is determined by the gate 7 which is opened by the clock pulse Tc.
The harmonic section adder 8 outputs the cumulative value QR to the calculation section timing signal
Timing 1 of clock pulse Tc within one cycle of
qR12qR, 3qR, . This accumulated value NqR is stored in the memory address decoder 9
After being decoded in , the sine function memory 10 is addressed by π and the sine amplitude value Sin-NqRW of each harmonic is read out in a time-divisional manner.

Such an operation is performed on sequential sample points of the musical sound waveform corresponding to the pressed key pitch every time the calculation interval timing signal Tx is generated. On the other hand, the memory address control device 11 counts clock pulses Tc in synchronization with the counter 4, and converts the count value into a harmonic order signal n.
By outputting as , the W order of the harmonic corresponding to the sine amplitude value Sin-NqR read out from the sine function memory 10 is specified.

Further, the touch detection circuit 18 detects the key touch (key press pressure, key press speed, etc.) corresponding to the signal output from the key switch circuit 1, and generates a digital signal corresponding to the key touch as a touch signal TD. Output.

Therefore, the touch signal TD changes depending on the state of the key touch. The harmonic order signal n and the touch signal TD thus generated are supplied to the harmonic coefficient memory 19 and address this memory 9.

In this case, the harmonic order signal n specifies the harmonic order,
Each touch signal TD has a set of harmonic amplitude coefficients C.
Specify any of the multiple memory groups that store 1 to CW and select harmonic coefficient memo I River 9 to harmonic amplitude coefficient CnT.
Read out. Therefore, if the touch signal TD is constant, a set of harmonic amplitude coefficients CnT stored corresponding to each harmonic order will be sequentially and repeatedly read out.
In this case, since the touch signal TD changes each time the key is pressed corresponding to the touch of the key, another group of the harmonic coefficient memory 19 is addressed by the touch signal TD and another set of harmonic coefficient memory 19 is created. The harmonic amplitude coefficients CnT of are sequentially read out. Therefore, a set of harmonic amplitude coefficients CnT having different values are read out according to changes in the touch signal TD. In this way, the harmonic amplitude coefficient CnT, which changes depending on the harmonic order signal n and the touch signal TD, is converted into the sine π-sine amplitude value Sin− of each harmonic output from the sine function memory 10 in the harmonic amplitude multiplier 13. Multiply by NqR to obtain the amplitude W of each harmonic
1 & Setting the value Fn(CnTsin-NqR), the evening τT
The T-touch signal TD, that is, the relative amplitude value Fn between each harmonic changes depending on the key touch associated with the key press operation, and accordingly, each harmonic is The accumulated value of the accumulator 15 that accumulates the wave amplitude value Fn changes.

Therefore, the sound system 17 generates musical tones whose timbre changes in accordance with the state of the key touch accompanying the key press operation. Note that in the embodiment described above, the harmonic order signal n and the touch signal T are independent of each other.
Addressed the harmonic coefficient memo I river 9 by D and,
A harmonic coefficient memory (a large number of harmonic amplitude coefficients CnTD is stored corresponding to various values of the multiplication value n·TD) using the harmonic order signal n and the multiplication value n-TD of the touch signal TD.

) may be configured to address. As explained above, according to the electronic musical instrument having the above configuration, it is possible to relatively change the value of the harmonic amplitude coefficient corresponding to each harmonic in relation to the key touch accompanying the key press operation, As a result, the timbre of the generated musical tone can be easily controlled variably by touching the key.

E. Another Embodiment of the Invention FIG. 3 is a block diagram showing another embodiment of the invention, in which the same parts as in FIG. 2 are designated by the same symbols.

In the figure, 20 and 21 are memory address control device 1.
The harmonic coefficient memory 20 is a harmonic coefficient memory whose address is controlled by the harmonic order signal n outputted from the harmonic order signal n output from the harmonic coefficient memory 20, and the harmonic amplitude coefficient Cln for each harmonic necessary to obtain the tone of the flute. are stored in the harmonic coefficient memory 21, and a harmonic amplitude coefficient C2n for each harmonic necessary to obtain the tone of the string is stored in the harmonic coefficient memory 21. 22 is a touch memory addressed by the harmonic order signal n and the touch signal TD, and each address of this touch memory 22 stores a plurality of sets of touch signals for each harmonic order, corresponding to the value of the touch signal TD. A coefficient GnT is stored.

23 and 24 are timbre selection switches and harmonic amplitude coefficients Cln
, c2n, respectively.

25 is an adder that adds the harmonic amplitude coefficients Cln and c2n from the timbre selection switches 23 and 24; 26 is an adder 25;
The harmonic amplitude coefficient Cn'-Cn-Gn is obtained by multiplying the output Cn by the touch coefficient GnT output from the touch memory 22.
This is a multiplier that outputs T.

In the electronic musical instrument configured in this way, the harmonic amplitude coefficient C is stored in the harmonic coefficient memories 20 and 21 by the harmonic order signal n output from the memory address control device 11.
ln and c2n are read respectively. Furthermore, the touch coefficient GnT corresponding to the harmonic order signal n and the touch signal TD is read out from the touch memory 22 by being addressed by the harmonic order signal n and the touch signal TD. For example, if the tone selection switch 23 is closed, the adder 2
5 outputs the harmonic amplitude coefficient Cln read from the harmonic coefficient memory 20 to the multiplier 26. The multiplier 26 multiplies the harmonic amplitude coefficient Cln and the touch coefficient GnT and supplies the harmonic amplitude coefficient Cn'GnT to the harmonic amplitude multiplier 13 to control the amplitude of each harmonic. As a result, the tone of the flute is A musical tone having a timbre is produced with the timbre changed by the touch coefficient GnT that changes according to the touch signal TD. Also,
If only the timbre selection switch 24 is closed, the musical tone having the timbre of the string will be produced with the timbre changed by the touch coefficient GnT which is changed by the touch signal TD. Therefore, the harmonic amplitude coefficient Cn7 when the timbre selection switch 23 is closed is as follows, and the harmonic amplitude coefficient Cn' when only the timbre selection switch 24 is closed is as follows.

Therefore, in the case of this configuration, the harmonic amplitude coefficients Cln and c2n determine the basic timbre of the generated musical tone, and the touch coefficient GnT determines the timbre change corresponding to the key setting. Become. Therefore, to change the basic timbre, it is only necessary to select the outputs of the harmonic coefficient memories 20 and 21 using the switches 23 and 24, and the timbre can be changed more effectively than in the case shown in Fig. 2. It is done. In addition, in the above-mentioned embodiment, the harmonic amplitude coefficient Cn (Cl
n or C2n)? Although the multiplier 26 is used to weight NT, the present invention is not limited to this, and any arithmetic unit that can weight both signals may be used. F. Effects of the Invention As explained above, the present invention provides an electronic musical instrument using a harmonic synthesis method, in which the value of the harmonic amplitude coefficient for each harmonic is calculated relative to the key touch associated with the key press operation. Since the timbre of the generated musical tone is changed subtly by the touch of a key, this has an excellent effect of producing a natural and rich performance sound.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an example of a conventional electronic musical instrument using a harmonic synthesis method, FIG. 2 is a block diagram showing an example of an electronic musical instrument according to the present invention, and FIG. 3 is a block diagram showing another example of an electronic musical instrument according to the present invention. FIG. 2 is a block diagram showing an example. 1... Key switch circuit, 2... Frequency number memory, 3... Clock oscillator, 4...
... Counter, 5, 7, 16 ... Gate, 6 ... Pitch section adder, 8 ... Harmonic section adder, 9 ... ...Memory address decoder, 10...Sine function memory, 11...
...Memory address control device, 13...Harmonic amplitude multiplier, 14...Accumulator, 16...
・D-A converter, 17...Sound system,
18...Touch detection circuit, 19, 20, 21.
...Harmonic coefficient memory, 22...Touch memory, 23, 24...Tone selection switch, 2
5... Adder, 26... Multiplier.

Claims (1)

[Claims] 1. A musical tone is generated by generating components corresponding to the fundamental wave and its harmonics constituting a musical tone, multiplying each component by an amplitude coefficient corresponding to each component, and adding the multiplied values. In a harmonic synthesis electronic musical instrument, there is a touch detection circuit that detects a key touch state associated with a key press operation, and a relative change in the value of each of the above amplitude coefficients in relation to the output of this touch detection circuit. An electronic musical instrument characterized by comprising amplitude coefficient changing means for changing the amplitude. 2. The electronic musical instrument according to claim 1, wherein the amplitude coefficient changing means is constituted by a memory addressed by a signal indicating the harmonic order and an output signal of the touch detection circuit. 3. A memory in which the amplitude coefficient changing means is addressed by a signal indicating the harmonic order and an output signal of the touch detection circuit, and a coefficient signal corresponding to the signal indicating the order and the output signal of the touch detection circuit is read out. 2. An electronic musical instrument according to claim 1, comprising: a computation means for computing the memory output and the amplitude coefficient.