JPH0358095A - Musical sound waveform signal generating device - Google Patents

Abstract

PURPOSE:To generate a musical sound which is extremely close to a rubbed string instrument electronically by providing a circulation signal path, 1st and 2nd signal delay means, an input means which composes a signal of input signals and outputs the composite signal, and a nonlinear deforming means. CONSTITUTION:The circulation signal path 21 corresponds to the string of the rubbed string instrument and a closed loop where a musical signal waveform signal circulates, and the loop consists of delay circuits 22 and 23, LPFs 24 and 25, multipliers 26 and 27, and adders 28 and 29. A signal is composed inside, respective parts are controlled with respective signals of a musical sound control signal generation part 13, and a nonlinear table 43 performs the nonlinear conversion of the signal with a specific function having hysteresis characteristics and inputs the result to a signal path 21. The LPF 45 functions to prevent oscillation, a formant filter 51 functions for the acoustic characteristics of a body, and a sound system 52 converts the input signal into an acoustic signal to generate a sound. Consequently, a scale, timbre, bow pressurization PRES, a bow speed, and other characteristics are controlled to generate a musical sound which is extremely close to the rubbed string instrument electronically.

Description

[Detailed description of the invention]

[Industrial Application Field 1] The present invention relates to a musical waveform signal forming device used in electronic musical instruments, music education devices, toys, etc., and particularly relates to a musical waveform signal forming device that forms a desired musical waveform signal while cyclically delaying a waveform signal. Concerning signal shaping equipment.

[Prior art]

Conventionally, this type of device has been disclosed, for example, in Japanese Patent Application Laid-Open No. 63-40199.
As shown in the publication, a nonlinear conversion circuit section is provided in the circulating signal path including the signal delay means, and the nonlinear conversion circuit section superimposes an external activation control signal on the waveform signal in the W ring. Then, the formation of a waveform signal is started in response to an external control signal, and a desired musical waveform signal is formed while the waveform signal is repeatedly circulated.

[Problem to be solved by the invention]

However, the conventional device described above is a wind instrument in which an air flow is blown from a mouthpiece provided at one end of the tube, and the air flow is reflected or transmitted within the tube to generate sound waves outside the tube. Although it is suitable for imitating sounds, it is not suitable for imitating the sounds of bowed string instruments such as violins and violas. The present invention has been made to address the above-mentioned problems, and its purpose is to provide a musical waveform signal forming device suitable for imitating the sounds of bowed stringed instruments. [Means for Solving the Problem] In order to achieve the above object, the above feature of the structure of the invention according to claim 1 is to provide a waveform signal! an 11th ring signal path, and a first and jlI signal path interposed in series in the W ring signal path
a second signal delaying means, inputting an external activation control signal, inputting each waveform signal on the circulating signal path between each of the first and second signal delaying means, and combining the inputted signals; A musical waveform signal is formed by an input means for outputting, and a nonlinear conversion means for performing nonlinear transformation on the composite signal output from the input means and outputting the resultant onto the circulating signal path between each of the first and second signal delay means. The invention according to claim 2 is characterized in that the nonlinear conversion means of the invention according to claim 1 is provided with a hysteresis characteristic. Further, the invention according to claim 3 is the musical waveform signal forming device according to the invention according to claim 1, in which a cyclic waveform signal is formed in the cyclic signal path between each of the first and second signal delay means. The object of the present invention is that transfer characteristic changing means for changing the transfer characteristics are respectively provided. Further, the invention according to claim 4 provides the musical waveform signal shaping device according to the invention according to claim 1, wherein at least one of the Ill and the second signal delay means is a variable delay means, The present invention includes musical tone control means that changes and controls the delay time of the waveform signal in the variable delay means in accordance with the frequency of the musical tone to be produced. Furthermore, the invention according to claim 5 is, in the musical waveform signal forming device according to the invention according to claim 1, wherein the nonlinear conversion means is constituted by variable nonlinear conversion means whose conversion characteristics can be changed; The present invention is provided with musical tone control means for changing and controlling the conversion characteristics of the nonlinear conversion means.

Function and effect of the invention 1 In the invention according to claim 1 configured as above,
When an external activation control signal is input to the input means, the control signal is guided to a circulating signal path via a nonlinear conversion means, and a waveform signal is passed through the first and second signal delay means on the same signal path. starts to circulate. At the same time, a part of this circulating waveform signal is input to the input means, and the input means causes the activation! ! It is combined with the 11l signal and outputted onto the circulating signal path via the nonlinear conversion means again. And the waveform signal circulating on the circulating signal path is ′! Since it is delayed by the total delay time by J1 and the second signal delay means, the previous f! The W circular waveform signal becomes a waveform signal having a period corresponding to the total delay time, and the periodic signal is subjected to nonlinear conversion of an external activation control signal and a circulating waveform signal by an input means and a nonlinear conversion means. Therefore, the nonlinear component is also always added. As a result, in the invention according to claim 1, in which a musical waveform signal is formed in this way, the vibration propagating or reflecting on the fixed strings at both ends by the VA ring signal path, the first and second signal delay means. According to the invention, it is possible to better imitate the state of waves, and also to better imitate the state of a bow scraping the middle part of a string using the input means and nonlinear conversion means. You will be able to perform forms. Further, in the invention according to claim 2, a hysteresis characteristic is given to the nonlinear transformation by the nonlinear conversion means. This better imitates the hysteresis characteristics caused by the friction phenomenon (static friction and dynamic friction) between the string and the bow when the string is displaced by rubbing it with the bow (imparting m-motion). According to the invention, it becomes possible to electronically form a musical tone closer to that of a bowed string instrument than in the invention according to claim 1. Further, in the invention according to claim 3, a desired transfer characteristic is imparted to the waveform signal circulating on the circulating signal path. This allows us to better imitate the vibration characteristics of strings.
According to the invention, compared to the invention according to claim 1, it becomes possible to electronically produce a musical sound closer to a bowed string instrument. Further, in the invention according to claim 4, since the musical tone control means variably controls the delay time by the first or second signal delay means in accordance with the frequency of the musical tone to be generated, that is, the musical tone is circulated on the circulating signal path. Since the period of the waveform signal is changed and controlled in accordance with the frequency of the musical tone to be generated, a musical waveform signal of a desired pitch is produced. This results in
In addition to the effects of the invention according to claim 1, the musical waveform signal forming device according to the invention can be applied to electronic musical instruments and the like, and its uses are expanded. Further, in the invention according to claim 5, the musical tone control means controls various changes in the conversion characteristics in the nonlinear conversion means, so that the musical sound waveform signal to be influenced can be changed in various ways. Accordingly, according to the same invention, said claim 1
Compared to the invention according to the above, various musical sound waveform signals can be generated depending on the type of bow and string, changes in pressure applied to the string, etc. [Embodiment] Hereinafter, an example in which a musical waveform signal forming device according to an embodiment of the present invention is applied to an electronic musical instrument will be explained using the drawings. FIG. 1 shows the entire electronic musical instrument as a block diagram. . This electronic musical instrument has a performance information generating section 11. The musical tone control signal generating section 13 includes a tone information generating section 12 and a musical tone control signal generating section 13, and controls the musical tone generated by the musical tone control signal generating section 13 based on the performance information from the performance information generating section 12 and the tone information number from the tone information generating section 12. The signal is supplied to a musical waveform signal forming section 20 to form a musical waveform signal for a bowed stringed instrument such as a violin or viola. The performance information generating section 11 includes a keyboard consisting of a plurality of keys corresponding to musical scales, a key press detection circuit that detects the presence or absence of a key press operation for each key, an initial touch detection circuit that detects the key press operation speed, and a key press pressure. Alternatively, it is equipped with various circuits associated with the keyboard, such as an aftertouch detection circuit that detects the depth of a key press, and performance information such as key information indicating the presence or absence of a key press and the pressed key, initial touch information, aftertouch information, etc. Output. The timbre information generating section 12 includes a timbre selection switch and an operation detection circuit for the switch, and outputs timbre information representing the selected timbre. The musical tone control signal generating section 13 is composed of, for example, a microcomputer, a musical tone control parameter storage table, etc., and refers to the table according to the performance information and timbre information to generate various musical tone control signals that do not change over time and various musical tone control signals that change over time. Outputs a musical tone control signal. These musical tone@control signals include, for example, the first and twelfth pitch signals PIT+ and PIT2 determined by the keys pressed in the aSS and representing the pitch of the generated musical tone as a sum value, initial touch performance information, and aftertouch performance information. and a bow speed signal VEL, which is determined based on the timbre information and represents the moving speed of the bow in the stringed instrument; a bow pressure signal PRES, which represents the pressure applied from the bow to the string when the bow is moving; and a bow pressure signal PRES, which is determined mainly by the timbre information. In addition, the timbre I111 signal Tl, +~T is determined with some consideration to the above-mentioned performance information and serves as a timbre control element.
It consists of C5. Note that if the electronic musical instrument is equipped with other performance controls such as wheels and pedals that are operated by the player, the performance information regarding the operation of each of these performance controls may be stored in the same manner as the initial touch and aftertouch. What performance +? fl
It may be treated as i. Furthermore, the performance information generating section 11
Other musical instruments, automatic performance devices, etc. may be employed as the tone color information N generation section 12, and performance information and tone color information may be supplied from the other musical instruments, automatic performance devices, etc. to the musical tone control signal generation section 13. In addition, the various musical tone control signals are generated in other musical instruments and automatic performance devices, so that the same musical tone Il is generated.
The l control signal may be directly supplied to the musical waveform signal forming section 20. The musical waveform signal forming section 20 has a closed loop circulation signal path 21 that circulates the musical waveform signal w1 in correspondence with the strings of a bowed stringed instrument. A filter 24.25, a multiplier 26.27 and an adder 28.29 are interposed in series. Delay circuit 22.
23, each delay time is variably controlled by the pitch signals PITI and PIT2, and the pitch of the generated musical tone is approximately determined by variable control of the pitch delay time. The low-pass filters 24 and 25 simulate the vibration characteristics of various strings by changing the transmission characteristics of the circulating waveform signals, and the characteristics are changed by the timbre control signals T C + and T C 2. Switching is controlled. Multiplier 26.27
By multiplying the circulating waveform signal by "1", the phase of the signal is shifted by π, and the condition for terminating the vibration wave at the fixed end of the string is realized. The waveform signal on the circulating signal 21 is supplied to an adder 31 at each output of the multipliers 26, 27. The adder 31 and the adder 32 constitute input means, and the output of the adder 31 is connected to one input of the adder 32, and the bow speed is connected to the other input of the adder 32. A signal VEL is supplied. Such an adder 3
1.32 is an adder 32 that simulates the displacement of the contact part of the bow on the string by the movement of the bow, and the displacement of the contact part by vibration waves traveling on the string.
The output of is input to the nonlinear table 43 via the adder 41 and the divider 42, and the output of the nonlinear table 43 is output onto the circulating signal path 21 via the multiplier 44 and adders 28 and 29. It looks like this. The nonlinear table 43 nonlinearly transforms the output from the adder 32 to simulate the state of string displacement caused by the movement of the bow, and the input/output characteristics of the table 43 are as shown by the solid line 11!21. The output characteristics are set. In other words, when the bow is rubbed against the string, when the bow speed is small, the frictional force between the bow and the string is mainly controlled by the coefficient of static friction, and the string speed becomes almost the same as the bow speed.
As the bow speed increases, the frictional force becomes mainly controlled by the dynamic friction coefficient, and the string speed becomes slower than the bow speed. This phenomenon is now realized by nonlinear transformation using the nonlinear table 43. ing. Note that the characteristics of this nonlinear table 43 are changed and controlled by a timbre control signal C3. The bow pressure signal PRES is input to both the divider 42 and the multiplier 44. The divider 42 divides the signal input to the nonlinear table 43 by the bow pressure signal PRES, and the multiplier 44 divides the signal input to the nonlinear table 43 by the bow pressure signal PRES. The signal is multiplied by the bow pressure signal PRES. These dividers 42 and multipliers 44 simulate the change in the nonlinear characteristics shown by the solid line in FIG. In other words, by dividing the input signal of the nonlinear table 43 by the bow pressure signal F'RES, the solid line characteristic in FIG. 2 is changed to, for example, the broken line characteristic in FIG. By multiplying the bow pressure signal PRES, the broken line characteristic in Fig. 2 becomes WI
By changing the characteristic shown by the dashed dotted line in FIG. 2, both calculations expand or reduce the string speed relative to the bow speed in a similar manner depending on the bow pressure. Further, the output of the multiplier 44 is fed back to the adder 41 via a low-pass filter 45 and a multiplier 46, and due to this feedback, the nonlinear conversion of the signal by the nonlinear table 43 including the divider 42 and the multiplier 44 is performed. , a hysteresis characteristic is provided. Let us specifically explain the operation of adding this hysteresis characteristic. Note that negative values such as -0.1, -0. 2
The adder 41 functions to subtract the output signal of the multiplier 46 from the output signal of the adder 32 and supply the result to the divider 42. Become. FIG. 3 is a graph for explaining this hysteresis characteristic, in which the relationship between the output of the adder 4l and the output of the multiplier 41 is shown by a chain line. For example, if the nonlinear conversion input (output of the adder 32) increases from zero in the positive direction, the nonlinear conversion output (output of the multiplier 44) increases proportionally along the solid line in FIG. Same input value
1. Since it shows a large positive value near X2, the amount of subtraction in the adder 41 also becomes large. When the nonlinear conversion input value reaches the value X1, the nonlinear conversion output value rapidly changes to a small value, and thereafter, as the input value increases, the output value gradually decreases while maintaining a small value. do. On the other hand, if the nonlinear input value decreases from this state, the nonlinear conversion output value is small, so the amount of subtraction in the adder 41 becomes small, and even if the nonlinear conversion input value is the same as in the above case, the input to the divider 42 The value will indicate a large value. Then, when the nonlinear transformation input value reaches 411 X 2, which is smaller than 4a X I, the nonlinear transformation output value suddenly becomes a large value. The same applies when the nonlinear conversion input value changes negatively, and due to this effect,
The hysteresis characteristic is realized. Further, the low-pass filter 45 functions to prevent oscillation, and the multiplier 46 functions to adjust the feedback gain.The timbre I1 control signal TC applied to the multiplier 46
The width of bisteresis is changed and controlled by J. Note that the characteristics of the low J pass filter 45 may also be changed and controlled by the sound @ control signal. Furthermore, the circulating signal j121 is sent to the adder 28 and the delay circuit 2.
3, it is connected to formant filter 51. This formant filter 51 simulates the acoustic characteristics of the body of a bowed stringed instrument, and gives the input signal a frequency characteristic switched and controlled by the timbre control signal TC6, and outputs it to the sound system 52. The sound system 52 includes an A/D converter, an amplifier, a speaker, etc., and converts an input signal into an audio signal and outputs it. Next, the operation of the embodiment configured as described above will be explained. When performance information such as key information, initial touch information, and aftertouch information is supplied from the performance information generation section 11 to the musical tone control signal generation section 13 in response to key press operations on the keyboard, the generation section 13 generates these information. Based on the performance information and the tone information supplied from the tone information generator 12, various fNs are generated.
The fli signal is output to the musical waveform signal generator m20. In the musical waveform signal forming section 20, an adder 32 inputs the supplied bow speed signal VEL and supplies it to a nonlinear table 43 via an adder 41 and a divider 42, and the table 43 inputs the bow speed signal VEL. VEL is non-linearly transformed and supplied to the adder 2829 via the multiplier 44. Adder 2
8.29 outputs the input signals to the circulation signal paths 21.21, respectively, and the output signals pass on the circulation signal 21 to delay circuits 22, 23, low-pass filters 24, 25, multipliers 26, 27, and It begins to circulate through adders 28 and 29. In such a case, the delay time of the delay circuits 22 and 23 is determined by the pitch signals PIT+ and P from the musical tone control signal generator 13.
Ih, and the total delay time of both delay circuits 22 and 23 is set to a value corresponding to the pitch period of the key pressed on the keyboard, so the time for one cycle on the circulation signal path 21 is The cycle becomes equal to the pitch period of the key, and the circulating signal becomes a waveform signal having the pitch period of the same key. Also, during the circulation of such waveform signals, the low-pass filters 24.25 output the timbre control signals TC+. A multiplier 26 controls the TCP to give the same waveform signal a frequency characteristic according to the string characteristics.
, 27 shift the phase of the same waveform signal by a certain amount to satisfy the string termination condition, so that such a circulating signal is a better simulation of the vibration wave traveling on the string. The circulating waveform signal is guided to the formant filter 51, and the filter S1 is controlled by the timbre control signal TCs.
The waveform signal is given a frequency characteristic that simulates the acoustic characteristics of the body of a bowed stringed instrument, and is supplied to the sound system S2. And this sound system 52
Since the waveform signal supplied to the system 52 is converted into an acoustic signal and produced, the produced musical tone is extremely similar to the musical tone produced through the body of a bowed stringed instrument due to string vibration. On the other hand, the aforementioned bow speed signal VEL continues to be supplied to the adder 32, and the waveform signal circulating on the Wi-ring signal path 21 is also supplied to this adder 32 via the adder 31. Therefore, this waveform signal and the bow velocity signal VEL are combined and input into the nonlinear table 43. As mentioned above, the nonlinear table 43 nonlinearly transforms this input signal and outputs it. By pressure signal PRES! ! The timbre Ig output from the musical tone control signal generator 13 is controlled by a feedback path including a low-pass filter 45 and a multiplier 46 to expand or reduce the nonlinear conversion output according to the signal PRES (see figure il2). I by control signal TC4
g is controlled, and a hysteresis characteristic is imparted to the nonlinear variable force according to the signal TC4 (see Figure 3), so the relationship between the bow and string of a bowed stringed instrument whose friction coefficient changes depending on the bow speed is improved. It is well simulated, and the musical tones produced by the sound system 52 are extremely close to the musical tones of a bowed string instrument. In the above embodiment, the division word 42 and the multiplier 4
4 is used to scale up and down the nonlinear conversion output, however, a large number of nonlinear tables 43 corresponding to this scaling may be prepared and the conversion tables may be switched in accordance with the bow pressure signal PRES. Further, although the bow velocity signal VEL and the cyclic waveform signal are non-linearly transformed using the non-linear table 43, the non-linear transform may be realized by calculation instead of using the table. Further, in the above embodiment, the output end of the cyclic waveform signal is provided between the adder 28 and the delay circuit 23, but if there is '' in the cyclic signal path 21, the output end of the cyclic waveform signal is provided from another location. You may also take it out.

[Brief explanation of drawings]

FIG. 1 is an overall block diagram of an electronic musical instrument equipped with a musical waveform signal forming device according to an embodiment of the present invention, and FIGS. 2 and 3 are graphs showing nonlinear conversion characteristics of the embodiment of FIG. 1. Explanation of symbols 11...Performance information generating section, 12...Tone color information generating section, 13...Music tone control signal generating section, 20...Musical sound waveform signal forming section, 21...Circulating signal path ,22.23...
Delay circuit, 24.25.45...low pass filter,
26, 27, 44. 46... Multiplier. 2
8, 29, 31, 32, 41... adder, 42...
Divider, 43...Nonlinear table.

Claims (5)

[Claims] (1) A circulating signal path for circulating a waveform signal, first and second signal delay means interposed in series in the circulating signal path, and receiving an external activation control signal and receiving the first and second signal delay means. input means for inputting each waveform signal on the circulating signal path between each of the second signal delay means and synthesizing and outputting the input signals; A musical waveform signal forming apparatus comprising: nonlinear conversion means for outputting onto the circulating signal path between each of the first and second signal delay means. (2) A musical waveform signal forming device in which the nonlinear conversion means according to claim 1 has a hysteresis characteristic. (3) In the musical waveform signal forming apparatus according to claim 1, a transfer characteristic changing means for changing the transfer characteristic of the circulating waveform signal in the circulating signal path between each of the first and second signal delay means. A musical waveform signal forming device is provided. (4) In the musical waveform signal forming device according to claim 1, at least one of the first and second signal delay means is constituted by a variable delay means, and the delay time of the waveform signal in the variable delay means is used to produce a sound. A musical sound waveform signal forming device is provided with musical tone control means for changing and controlling the frequency of a musical tone to be played. (5) In the musical waveform signal forming device according to claim 1, the nonlinear conversion means is constituted by variable nonlinear conversion means whose conversion characteristics can be changed, and the conversion characteristics of the variable nonlinear conversion means are controlled to change. A musical waveform signal forming device provided with musical tone control means.