JP3378066B2 - Music synthesizer - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tone synthesizer for synthesizing a plurality of tone signals and synthesizing a tone signal having a tone different from the plurality of tone signals. 2. Description of the Related Art Conventionally, as a musical tone synthesizing apparatus as described above, for example, there is an apparatus disclosed in Japanese Utility Model Publication No. 63-15914. This has an address generation circuit 2 as shown in FIG. 9, which repeatedly generates an address signal at a predetermined period T as shown in FIG.
This address signal is supplied to the waveform generation circuit 4 and
A tone waveform having a period T is repeatedly generated as shown in FIG. The tone waveform is supplied to the selection circuit 6.
The selection circuit 6 is also supplied with a signal V _{0 of a} constant level. The address signal from the address generating circuit 2 is also supplied to an address discriminating circuit 8, and when the value of the address signal is within a predetermined range, the address discriminating circuit 8 shown in FIG. A switching signal as shown is supplied to the selection circuit 6. The selection circuit 6 selects and outputs the tone waveform from the waveform generation circuit 4 when the switching signal is not supplied, but selects and outputs the signal V ₀ when the switching signal is supplied. Therefore, from the selection circuit 6, FIG.
(D), the portion of the musical tone waveform from the waveform generating circuit 4 is signal substitution constant level signal V ₀ is outputted. However, in the above-described tone synthesizer, it is determined whether or not the value of the address signal for reading the tone waveform is within a predetermined range, and the tone waveform is synthesized. It is determined whether or not to replace the signal V ₀ with a constant level. Therefore, it can be used only for a musical tone waveform generated by reading by an address signal.For example, a part of a musical tone waveform from a natural musical instrument cannot be replaced with another waveform, and the use range is limited. There was a problem that it was narrow. In order to solve the above problems, the present invention provides an input terminal for inputting a waveform signal and a characteristic for detecting characteristics of the waveform signal input from the input terminal. A tone signal waveform generator for generating a tone signal waveform corresponding to the waveform signal in accordance with a detection result of the characteristic detector, the input waveform signal input from the input terminal, and the tone signal. Selecting means for selectively outputting the tone signal waveform from the waveform generating means; comparing means for comparing the input waveform signal input from the input terminal with a predetermined level signal to control the selecting means; To
It is provided. According to the present invention, according to the present invention, depending on whether the level of the input waveform signal is higher or lower than the predetermined level signal, the selecting means converts the input waveform signal or the tone signal waveform. select. That is, the signal selected by the selection means is replaced with the tone signal waveform from the input waveform signal according to the level of the input waveform signal. In particular, the tone signal waveform replaced from the input waveform corresponds to the input waveform signal. FIG. 1 and FIG. 2 show a first embodiment of the present invention. This embodiment has an input terminal 10 to which an input waveform signal obtained by detecting vibration of a string of an electric guitar or the like by a pickup and digitizing the input signal is supplied. This input waveform signal is supplied to selection means, for example, a contact 12a of the changeover switch 12. The input waveform signal is supplied to a characteristic detecting means of the tone signal waveform generating means 14, for example, the pitch detecting means 1;
6. The pitch detecting means 16 detects the pitch of the input waveform signal, and outputs the detected signal to the pitch calculating means 18.
To supply. The pitch calculating means 18 converts a signal having a pitch that is an integral multiple of the pitch of the input waveform signal into an oscillator
The incremental data to be generated to 0 is calculated and supplied to the oscillator 20. The oscillator 20 has a register 22 for storing the increment data from the pitch calculating means 18. The pitch data is accumulated by an accumulator comprising an adder 24 and a register 26, as shown in FIG. 2 (b). It generates a simple sawtooth signal. As described later, when the input waveform signal becomes negative, the register 26 is cleared to 0 by a signal from the comparator 34 described later, and the value of the register 26 and the increment data of the register 22 (the increment data is negative). Is added by the adder 24 and stored in the register 26. After a certain time, this register 2
6 and the increment data of the register 22 are added. In the same manner, the value of the register 26 gradually decreases and eventually overflows, and the overflow data is gradually reduced by the increment data. By repeating this, a sawtooth signal is generated. The incremental data is determined so that the pitch of the sawtooth signal is an integer multiple of the input waveform signal, that is, the pitch is synchronized. The sawtooth signal from the oscillator 20 is supplied to a multiplier 28, where the signal is calculated as level adjustment data. The level adjustment data is detected by a characteristic detecting means to which an input waveform signal of the input terminal 10 is supplied, for example, a level detecting means 30, and is calculated by a level calculating means 32 based on the level detecting signal. 2
The signal output from 8, ie, the tone signal waveform, is calculated so as to correspond to the level of the input waveform signal. The tone signal waveform from the multiplier 28 is supplied to the contact 12b of the changeover switch 12. The changeover switch 12 has a contact 12c in addition to the contacts 12a and 12b, and the contact 12c is controlled in accordance with an output of a control means, for example, a comparator 34. The comparator 34 compares the input waveform signal of the input terminal 10 with the threshold value 0, and connects the contact 12c to the contact 12a while the input waveform signal is positive. Is connected to the contact 12b. Therefore, contact 1
While the input waveform signal is output to the output terminal 36 connected to the terminal 2c while the input waveform signal is positive, the tone signal waveform from the multiplier 28 is supplied during the input waveform signal is negative. Is done. For example, when an input waveform signal as shown in FIG. 2A is supplied to the input terminal 10, and when the input waveform signal is positive as in the period T1, the comparator 34 connects the contact 12c to the contact 12a side. Has been switched to. Therefore, FIG.
As shown in (c), the input waveform signal is output to the output terminal 36 via the changeover switch 12 as it is. The pitch data is determined by the pitch detecting means 16 and the pitch calculating means 18 during the period T1 or in the period of the waveform signal before the period T1, which is not described, and is stored in the register 32. . The pitch detecting means 16 detects the pitch one by one. When the pitch is detected, the pitch data is updated so that it can cope with a temporal change of the pitch. In a portion where a pitch cannot be detected, such as a rising portion of a tone signal of an electric guitar, the control of the changeover switch 12 by the comparator 34 is prohibited, and the input signal is output as it is. In the period T2, since the input waveform signal is negative, the comparator 34 switches the contact 12c to the contact 12b. As described above, during the period T2, the oscillator 20
Generates a sawtooth signal, the level of which is adjusted by the multiplier 28 and supplied to the contact 12b. Therefore, as shown in FIG. 2C, when the input waveform signal is in a negative period,
Instead of the input waveform signal, a tone signal waveform in which the level of the sawtooth signal from the oscillator 20 is adjusted is output to the output terminal 36. As described above, when the saw-tooth wave signal from the oscillator 20 and the input waveform signal due to the string vibration of the electric guitar are selected and output every half cycle of the input waveform signal, an intermediate tone between the two can be obtained. In particular, the nuance of a live musical instrument such as an electric guitar can be added to the musical sound from the oscillator 20. In general, the oscillating sound of an oscillator cannot express the nuances of a live instrument, and it is difficult to create an intermediate tone between the oscillating sound of an oscillator and a live instrument.This embodiment solves these problems. it can. FIG. 3 shows a second embodiment. In the first embodiment, the pitch of the sawtooth signal generated by the oscillator 20 is adjusted so as to be an integral multiple of the pitch of the input waveform signal. In the second embodiment, the signal oscillated by the oscillator 20a is adjusted. (The pitch is not limited to the sawtooth wave.) The pitch is fixed independently of the pitch of the input waveform signal. Therefore, when switching from the input waveform signal to the signal of the oscillator 20a, or when switching from the signal of the oscillator 20a to the input waveform signal, the waveform becomes discontinuous and noise may be generated. To compensate for this, in this embodiment, the signal from the oscillator 20a is multiplied by the multiplier 38 with the window function signal generated by the window function reading circuit 40. The window function readout circuit 40 receives the one-shot circuit 42 when the input waveform signal level changes from positive to negative, that is, when it crosses zero, and thereafter, in response to the signal generated by the comparator 34, that is, when it crosses zero. Generates a window function signal in accordance with the signal generated by. The generated window function signal is determined by the pitch detecting means 16 and the pitch calculating means 18 according to the pitch of the input waveform signal. Although the multiplier 38 is provided on the output side of the oscillator 20a, it can be provided on the output side of the level calculation means 32 as shown by a dotted line. FIGS. 4 and 5 show a third embodiment. First
In the second embodiment, the signals generated by the oscillators 20 and 20a are standing waves, but in the third embodiment,
As shown in FIG. 4, the oscillator 20b is a one-shot circuit, and generates a one-shot sawtooth signal in response to the input waveform signal changing from positive to negative as shown in FIG. 5B. It is like that. Therefore, pitch detecting means 16 for detecting the pitch of the input waveform signal.
Also, no pitch calculating means 18 for determining the pitch of the oscillator oscillation signal is provided. Therefore, the circuit configuration can be simplified. FIGS. 6 and 7 show a fourth embodiment. First
In the embodiment, the switching from the input waveform signal to the tone signal waveform is performed when the input waveform signal level changes from positive to negative, that is, the threshold value is set to 0, but in the fourth embodiment, A threshold level source 44 is provided to set the threshold to an arbitrary level V as shown in FIG. Except for this point, the configuration is the same as that of the first embodiment. In this case, when the input waveform signal is switched to the tone signal waveform as shown in FIG. 7C, the level V is stored in the register 26 of the oscillator 20 as an initial value in order to maintain continuity. Is set. As described above, since the threshold level is set to V instead of 0, the section for switching to the tone signal waveform from the oscillator 20 can be set to a section other than a half cycle, and a tone different from that of the first embodiment can be obtained. . Note that this threshold level can be modulated using LFO or the like. FIG. 8 shows a fifth embodiment. In this embodiment, a signal obtained by amplitude-modulating the input waveform signal with a tone signal waveform is output during a period in which the level of the input waveform signal is negative. Therefore, an input waveform signal is supplied from the input terminal 10 to the modulation section 46, and a signal for modulating the input waveform signal is supplied to the modulation section 46 via the changeover switch 12. The signal of “1” is supplied to the contact 12 a of the changeover switch 12, and the tone signal waveform is supplied to the contact 12 b from the multiplier 28. The comparator 34 switches the contact 12c to the contact 12a while the input waveform signal is positive. Therefore, since “1” is supplied as a signal to be modulated to the modulator 46, the output signal from the modulator 46 is the input waveform signal itself. On the other hand, since the contactor 12c is switched to the contact 12b by the comparator 34 during the negative period of the input waveform signal, the tone signal waveform is supplied to the modulator 46 as a signal for modulating the input waveform signal, and the input waveform signal is converted to the tone signal waveform. The signal amplitude-modulated by the output terminal 36
Is supplied from the modulation unit 46 to In this embodiment, the signal for modulating the input waveform signal to be input to the modulation section 46 is switched by the changeover switch 12.
, And outputs the output signal of the modulating section 46 to the contact 1a.
2b, and the contact 12c may be switched by the output of the comparator 34. In this case, the output signal of the multiplier 28 may be supplied to the modulator 46 as a signal for modulating the input waveform signal. In the first embodiment, the oscillator 20 generates a saw-tooth waveform signal using overflow. However, a memory storing a tone signal waveform is used, and the tone signal waveform is read from this memory. It may be a thing. In this case, the tone signal waveform may be read from the memory in a loop, or the tone signal waveform may be read only once using a one-shot circuit. Further, a signal obtained by converting the output of the oscillator 20 into a non-linear tone signal waveform using a non-linear table may be used. In each of the above embodiments, the input terminal 10
Although the input waveform signal supplied to the input terminal is a signal from a live musical instrument, a signal from an oscillator similar to the oscillator 20 may be supplied to the input terminal 20. Further, the comparator 34
Uses a single level comparator as the comparison value, but uses a window comparator that detects that the comparison value is between two values or outside the two values.
It is also possible to output the oscillator signal between or outside the two values. As described above, according to the present invention, a part of the input waveform signal supplied to the input terminal is converted to a tone corresponding to the input waveform signal according to the characteristics of the input waveform signal. Since the signal waveform is replaced with a signal waveform, an intermediate tone between the input waveform signal and the tone signal waveform can be obtained. In particular, since the replacement is performed based on a comparison between the level of the input waveform signal and a predetermined level signal, even if the musical tone of the live musical instrument whose address cannot be read is the input waveform signal, this is compared with the musical tone signal waveform. You can get an intermediate musical tone.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram of a first embodiment of a musical sound synthesizer according to the present invention. FIG. 2 is a waveform chart of each part of the first embodiment. FIG. 3 is a block diagram of the second embodiment. FIG. 4 is a block diagram of the third embodiment. FIG. 5 is a waveform chart of each part of the third embodiment. FIG. 6 is a partially omitted block diagram of the fourth embodiment. FIG. 7 is a waveform chart of each part of the fourth embodiment. FIG. 8 is a block diagram of the fifth embodiment. FIG. 9 is a block diagram of a conventional tone synthesizer. FIG. 10 is a waveform chart of each part of the tone synthesis device of FIG. 9; [Description of Signs] 10 Input terminal 12 Changeover switch (selection means) 14 Musical tone signal waveform generation means 16 Pitch detection means (characteristic detection means) 20 Oscillator 30 Level detection means (characteristic detection means) 34 Comparator (comparison means) 46 Modulation unit (Modulation means)

Claims (1)

(57) Claims 1. An input terminal for inputting a waveform signal, and characteristic detecting means for detecting a characteristic of the waveform signal input from the input terminal, wherein a detection result of the characteristic detecting means is provided. A tone signal waveform generating means for generating a tone signal waveform corresponding to the waveform signal according to the following: selecting the input waveform signal input from the input terminal and the tone signal waveform from the tone signal waveform generating means And a comparing means for comparing the input waveform signal input from the input terminal with a predetermined level signal and controlling the selecting means.