JP2005250357A - Distortion effect device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a distortion device forming a proper musical sound by imparting distortion to an inputted musical signal. <P>SOLUTION: A desired frequency characteristic and a gain are respectively imparted to an inputted musical signal respectively by a pre-filter 22 constituting a pre-processing part 20 and a multiplier24. A level detection part 62 detects the envelope level of the inputted musical signal and a control part 70 controls a frequency characteristic of the pre-filter 22 and a gain of the multiplier 24 and a mode of effect of an effect part 50 according to the level. Concretely, when the level of the musical signal is large, the part 70 amplifies a musical signal whose frequency band is restricted greatly by making the frequency characteristic of the filter 22 to be a characteristic in which a low frequency band and a high frequency band are cut and by imparting a coefficient having a large value to the multiplier 24. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a distortion effect device that imparts a distortion effect to an input musical sound signal.

Conventionally, a distortion effect device that amplifies an input musical sound signal and distorts the waveform by clipping the waveform is known. Japanese Patent No. 314959 (Patent Document 1) discloses that the level of an input tone signal is changed by changing the mixing ratio of a signal obtained by performing distortion processing on the input tone signal and the input tone signal in accordance with the level of the input tone signal. There is disclosed a distortion effect device that outputs a musical sound with a large proportion of distortion signal when the signal is large, and outputs a musical sound with a large proportion of input musical signal when the level of the input musical signal is small.
Japanese Patent No. 3149559

  However, the distortion effect device described in Patent Document 1 only changes the mixing ratio of the input musical sound signal and the distortion signal to which high gain (high gain) distortion has already been applied. Even if the level is low, distortion signals to which high gain distortion is applied are mixed at a predetermined ratio, and a clean sound without distortion is not output completely. That is, there is a first problem that the dynamic range is narrow and lacks expressive power. In addition, since the mixing ratio is controlled by the level of the input tone signal, when the level of the input tone signal changes, the output signal has a large proportion of distortion signal and the input tone signal (so-called raw sound) has a large proportion. There is a second problem that it is difficult to perform with a stable output signal. There is also a third problem that an effect suitable for an output signal in which an input musical sound signal and a distortion signal are mixed at a predetermined mixing ratio cannot be given.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a distortion effect device that can distort an input musical sound signal and form an appropriate musical sound.

  In order to achieve this object, the distortion effect device according to claim 1 includes an input means for inputting a musical sound signal, a preprocessing section for imparting frequency characteristics and gain to the musical sound signal input to the input means, Level detection means for detecting the level of a musical tone signal between the input means and the output of the preprocessing section, and the frequency characteristics and gain provided by the preprocessing section in accordance with the level detected by the level detection means. Control means for controlling, and distortion imparting means for imparting distortion to the musical sound signal output from the pre-processing unit are provided.

  The distortion effect device according to claim 2 is the distortion effect device according to claim 1, wherein the pre-processing unit gives a first frequency characteristic and a first gain to the musical sound signal input to the input means. A first processing means for applying a second frequency characteristic different from the first frequency characteristic and a second gain different from the first gain to the musical sound signal input to the input means. 2 processing means, and mixing means for mixing the output of the first processing means and the output of the second processing means, the control means according to the level detected by the level detection means The mixing ratio of the mixing means is controlled.

  A distortion effect device according to a third aspect of the present invention is the distortion effect device according to the first or second aspect, wherein the level detection means detects the level of the tone signal output from the pre-processing unit.

  A distortion effect device according to a fourth aspect of the present invention is the distortion effect device according to any one of the first to third aspects, further comprising an effect imparting unit that imparts an effect to the musical sound signal that is distorted by the distortion imparting means. The control unit further controls the mode of the effect imparted by the effect imparting unit according to the level detected by the level detection unit.

  The distortion effect device according to claim 5 is an input means for inputting a musical sound signal, a preprocessing section for imparting frequency characteristics to the musical sound signal input to the input means, and a musical sound signal output from the preprocessing section. A level of the tone signal between the input means and the output of the pre-processing unit, a strain imparting unit that imparts a distortion to the sound signal, an effect imparting unit that imparts an effect to the tone signal that is distorted by the strain imparting unit And a control means for controlling the frequency characteristics provided by the preprocessing unit and the mode of the effect provided by the effect applying unit according to the level detected by the level detecting unit. Yes.

  The distortion effect device according to claim 6 is the distortion effect device according to claim 5, wherein the preprocessing unit provides a first frequency characteristic to the musical sound signal input to the input means. Means, second processing means for imparting a second frequency characteristic different from the first frequency characteristic to the musical tone signal input to the input means, an output of the first processing means, and the second Mixing means for mixing the output of the processing means, and the control means controls the mixing ratio of the mixing means in accordance with the level detected by the level detection means.

  The distortion effect device according to claim 7 is the distortion effect device according to any one of claims 4 to 6, wherein the effect applying unit includes a first effect processing unit that applies a first effect, and the first effect processing unit. Second effect processing means for applying a second effect different from the effect of the control means, and the control means is provided by the first effect processing means according to a level detected by the detection means. The ratio between the first effect and the second effect provided by the second effect processing means is controlled.

  According to the distortion effect device of the first aspect, the pre-processing unit for giving the frequency characteristic and the gain to the inputted musical sound signal is provided, and the frequency characteristic and the gain are controlled according to the level of the inputted musical sound signal or the like. Then, since distortion is applied, the dynamic range is expanded by the gain difference applied by the preprocessing unit according to the level of the input musical sound signal or the like while actively making the sound by the preprocessing unit. Therefore, depending on the level of the input musical sound signal (for example, in the case of a guitar, this corresponds to the strength of playing a string), the dynamic range ranges from a distortion sound with high gain distortion to a clean sound with no distortion at all. There is an effect that it is possible to play a wide variety of sharp sounds, and the first problem can be solved.

  According to the distortion effect device of the second aspect, in addition to the effect produced by the distortion effect device according to the first aspect, the preprocessing unit is processed by a plurality of processing means having different frequency characteristics and gains, respectively, Therefore, each frequency characteristic can be obtained with a simple configuration, and the frequency characteristic and the gain can be changed in accordance with the level of the tone signal.

  According to the distortion effect device of the third aspect, in addition to the effect produced by the distortion effect device according to the first or second aspect, the level detection means detects the level of the tone signal output from the preprocessing unit. As a result, it is easy to stably maintain the output signal of the musical sound, and there is an effect that it is easy to perform. That is, when the gain is controlled according to the level of the input signal, the gain changes immediately. However, when the gain is changed according to the level after gain adjustment, the gain becomes stable and difficult to change. For example, when the gain is increased by playing strongly once, the large gain is fed back and acts in the direction of increasing the gain, so that the gain remains large even if played slightly weakly. As a result, the second problem can be solved.

  According to the distortion effect device of the fourth aspect, in addition to the effect produced by the distortion effect device according to any one of the first to third aspects, the device further includes an effect imparting unit that imparts an effect to the tone signal to which distortion has been imparted. Since the mode of the effect is controlled according to the level detected by the level detecting means, the optimum effect is given to the output signal in which the input musical sound signal and the distortion signal are mixed at a mixing ratio corresponding to the strength of the performance. The third problem can be solved.

  According to the distortion effect device of the fifth aspect, the pre-processing unit for imparting the frequency characteristic to the inputted musical sound signal is provided, the frequency characteristic is imparted according to the level of the inputted musical sound signal and the like. Since the waveform is distorted and an effect corresponding to the level is given to the distorted musical sound signal, there is an effect that an optimal effect can be given to the musical sound given the distortion of the frequency characteristic according to the level, The third problem can be solved.

  According to the distortion effect device of the sixth aspect, in addition to the effect produced by the distortion effect device according to the fifth aspect, the preprocessing unit is processed by a plurality of processing means having different frequency characteristics to be applied, and these are mixed. Therefore, each frequency characteristic can be obtained with a simple configuration, and there is an effect that the frequency characteristic can be changed according to the level of the tone signal.

  According to the distortion effect device of the seventh aspect, in addition to the effect produced by the distortion effect device according to any one of the fourth to sixth aspects, a plurality of effect processing means having different effect types are provided, and the level of the musical sound signal is adjusted. Accordingly, since the ratio of a plurality of effects is controlled, there is an effect that an optimum effect can be imparted to a musical tone to which an optimum frequency characteristic distortion is imparted according to the level.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a block diagram of a distortion effect device 1 of the present invention. A musical tone signal input from an electric guitar pickup or microphone is sampled by an A / D converter 10 at a predetermined sampling frequency (for example, 44.1 kHz) and quantized into a digital signal having a predetermined number of bits (for example, 16 bits). And supplied to a DSP (digital signal processor) 11.

  The DSP 11 performs various kinds of signal processing on the musical tone signal and supplies it to the D / A converter 12. The D / A converter 12 converts the supplied digital signal into an analog signal and outputs the analog signal. The output musical sound signal is emitted by an amplifier, a speaker, etc. (not shown). The DSP 11 includes a ROM that stores a program (not shown) and a RAM that temporarily stores programs and parameters.

  A CPU (Central Processing Unit) 13 executes a program stored in the ROM 14, uses the RAM 15 temporarily stored as a work area, and executes a parameter or a process executed by the DSP 11 based on a value set by the operator 16. A program and the like are set and transmitted to the DSP 11.

  FIG. 2 is a block diagram showing a first embodiment of processing in the DSP 11. The musical sound signal input to the input unit 18 of the DSP 11 is given a desired frequency characteristic by the pre-filter 22 constituting the pre-processing unit 20 and given a gain by the multiplier 24. The pre-filter 22 is composed of a digital filter, and the frequency characteristic can be changed by changing each coefficient of the digital filter. The musical tone signal output from the multiplier 24 is then shaped in the clip processing unit 30 so that the amplitude equal to or greater than a predetermined amplitude value becomes a constant amplitude value. This adds distortion to the waveform and includes many overtones. Next, the post filter 40 gives a frequency characteristic to the musical sound signal to which distortion has been applied, and the effect applying unit 50 gives a desired effect and outputs it.

  On the other hand, the musical tone signal input to the input unit 18 and the output signal of the preprocessing unit 20 are respectively input to one end of the changeover switch 60, and one of them is selected and input to the level detection unit 62. The level detection unit 62 detects the envelope level of the input musical sound signal, and the control unit 70 determines the frequency characteristics of the prefilter 22, the gain of the multiplier 24, and the effect of the effect applying unit 50 according to the level. To control. Specifically, when the level of the tone signal detected by the level detection unit 62 is high, the frequency characteristic of the pre-filter 22 is set to a characteristic that cuts low and high frequencies, and overtones generated by the subsequent clip processing unit 30 are used. Among them, unnecessary harmonics that make the sound muddy are limited.

  Further, a large value coefficient is given to the multiplier 24 to greatly amplify a musical sound signal with a limited frequency band so that deep distortion is applied by the clip processing unit 30. Further, the effect imparting unit 50 is set with an optimum effect mode for distortion sound with deep distortion.

  On the other hand, when the level of the tone signal detected by the level detector 62 is small, a flat frequency characteristic is set for the pre-filter 22 or rather a frequency characteristic with a slightly raised low and high frequencies is set. A relatively small coefficient is set in the multiplier 24 so that shallow distortion is applied by the clip processing unit 30. In the effect imparting unit 50, an optimum effect mode is set for a clean sound with shallow distortion. In the effect imparting unit 50, when delay is set as the type of effect, the delay level is set large when the level of the tone signal is large, and the delay level is set small when the level is small. In addition, when chorus is set as an effect, the depth is set small when the level of the musical sound signal is high, and the depth is set large when the level is low. The frequency characteristic of the post filter 40 is a characteristic formed by a secondary low-pass filter having a cutoff frequency of about 2.5 kHz and a filter having a peak at about 125 Hz as shown in FIG. .

  When the changeover switch 60 is set to the input musical sound side, the transition between the distortion sound and the clean sound is quickly changed according to the level of the input musical sound, and the changeover switch 60 is set to the output side of the preprocessing unit 20. In this case, since the coefficient of the multiplier 24 in the preprocessing unit 20 is set according to the output level of the preprocessing unit 20, the transition between the distortion sound and the clean sound becomes slow, and the performance with the stable output signal is performed. It can be performed. The changeover switch 60 may be set by the user, or may be set in advance by a manufacturer as a preset together with a filter and an effect parameter.

  FIG. 3 is a processing block diagram showing the second embodiment. The same parts as those in the first embodiment are denoted by the same part numbers. The pre-processing unit 20 mixes the first processing means composed of the prefilter A100 and the multiplier A102, the second processing means composed of the prefilter B104 and the multiplier B106, and the outputs of these processing means. The premixer 108 is configured. The first processing means is a setting for forming a distortion sound that deeply applies distortion, and the frequency characteristic of the pre-filter A100 is a second-order low-pass having a cutoff frequency of about 2 kHz as shown in FIG. This is a combination of a filter, a primary high-pass filter with a cutoff frequency of about 660 Hz, and a primary high-pass filter with a cutoff frequency of about 330 Hz.

  The second processing means is a setting for forming a clean sound without distortion. As shown in FIG. 4B, the frequency characteristic of the pre-filter B104 raises about 1 kHz or more by 3 dB and raises about 165 Hz or less by 6 dB. It is a characteristic formed by a shelving filter. In this way, by providing the frequency characteristics with the second processing means, it is possible to positively form a timbre when distortion is not so much applied.

  A gain A is set for the multiplier A102, and a gain B is set for the multiplier B106. The gain A is set to a value sufficiently larger than the gain B. The signals to which these gains are given are added by the premixer 108 after being multiplied by a coefficient corresponding to the mixing ratio, which is a control signal from the control unit 70. The values of gain A and gain B may be arbitrarily set by the user as will be described later.

  Next, the output of the preprocessing unit 20 is given a constant gain by the total gain unit 110, and the clip processing unit 30 is distorted by limiting the level to a predetermined value or less, and the post filter 40 has a frequency characteristic. Is granted.

  Further, the output of the total gain section 110 is input to one terminal of the changeover switch 60, and the input musical sound signal is directly input to the other terminal, and either one is selected. The envelope level of the signal selected by the changeover switch 60 is detected by the level detection unit 62. The control unit 70 controls the mixing ratio in the premixer 108 and the effect mixer 124 based on the detected level. Specifically, when the level detected by the level detection unit 62 is large, the output ratio of the first processing unit is increased, and when the level detected by the level detection unit 62 is small, the second processing unit Increase the output rate.

  The effect applying unit 50 includes an effect processing unit A120, an effect processing unit B122, and an effect mixer 124. As an example, the effect processing means A120 provides a delay (or reverb) as the effect type, and the effect processing means B122 provides a chorus and the level detection unit 62 detects a large level. In this case, the effect mixer 124 is controlled according to the control signal from the control unit 70 so that the delay is added as an effect and the level detected by the level detection unit 62 is small, and the chorus is added as the effect. The

  Therefore, when the level detected by the level detection unit 62 is large, the pre-processing unit 20 gives an optimum frequency characteristic and gain for giving a deep distortion, and the clip processing unit 30 gives a deep distortion, giving an effect. The portion 50 provides a large delay effect. On the other hand, when the level of the input musical sound signal is small, the pre-processing unit 20 gives an optimum frequency characteristic and gain for applying shallow distortion, the clip processing unit 30 gives shallow distortion, and the effect applying unit 50 Many chorus effects are imparted.

  FIG. 5 shows details and a modification of the effect imparting unit 50. (A) shows the details of the effect mixer 124. The output of each of the effect processing means A120 and the effect processing means B122 is provided with a multiplier, and if one coefficient is e, the other coefficient is 1-e. After multiplication, it is added.

  (B) is an example in which a multiplier is arranged in front of each effect processing means. In this case, the waveform of the delay is stored in the delay memory, so when the mixing ratio is changed and the delay is switched to the chorus, the delay output is not immediately silenced and is natural. Switching takes place.

  In (c), for the chorus, the multiplier is provided on the output side, and for the delay, the multiplier is provided on the input side.

  FIG. 6 is an operation panel diagram of the distortion effect apparatus 1 and shows various operators 16. The input jack 300 is used to input an output signal from an electric guitar or an electronic musical instrument. The gain A 302 and the gain B 304 are for setting the coefficients of the multiplier A 102 and the multiplier B 106 shown in FIG. The master volume 306 sets the volume of the musical sound signal that is finally output. The master volume 306 is provided with a multiplier (not shown) at the output of the effect applying unit 50 and sets its coefficient. The chorus 308 and the delay 320 set parameters of the effect to be applied by the effect applying unit 50. In the chorus 308, the chorus rate is set, and in the delay 320, the delay time of the delay is set. When the effect processing means A is a reverb, the reverberation time may be set.

  The power switch 310 is a switch for turning on or off the power of the present distortion effect apparatus. Although the base 312, the middle 314, the treble 316, and the presence 318 are not shown in FIGS. 2 and 3, an equalizer is formed between the input unit 18 and the preprocessing unit 20, and the user can arbitrarily set the frequency characteristics of the equalizer. It is a knob for setting. The phone 322 is a headphone jack.

  The present invention has been described above based on the above embodiments, but the present invention is not limited to the above embodiments, and various improvements and modifications can be made without departing from the spirit of the present invention. It can be easily guessed.

  For example, in the above embodiment, the level detection unit 62 detects the level of either the input musical sound signal or the output of the preprocessing unit 20, but the prefilter 22 of the preprocessing unit 20 in FIG. Or the output level of the prefilter A100 or prefilter B104 in FIG. 3 may be detected. The “musical sound signal level between the input means and the output of the preprocessing unit” in the claims corresponds to a level detected by any one or a plurality of points.

  Further, the control unit 70 may change the frequency characteristics of the post filter 40 according to the level detected by the level detection unit 62. For example, if the post filter is a low-pass filter, the distortion is deep when the level is large, and the cut-off frequency of the low-pass filter is set slightly low, and the cut-off frequency is set high when the level is small.

  In the second embodiment, the outputs of the two processing means of the first processing means and the second processing means are mixed. However, three or more processing means are provided and their outputs are mixed. It may be a thing.

  In the panel of FIG. 6, the user can set the coefficients of the multiplier A102 and the multiplier B106, but one may be a fixed value and the other may be variable.

  In the second embodiment, the total gain 110 is multiplied by a fixed coefficient. However, the total gain 110 may be set by the user or may be changed according to the level detected by the level detection unit 62. .

It is a block diagram of the distortion effect apparatus of this invention. It is a block diagram which shows the processing structure of DSP of a 1st Example. It is a block diagram which shows the process structure of a 2nd Example. It is a figure which shows the frequency characteristic of each filter. It is a figure which shows the detail and modification of an effect provision part. It is a panel figure of a distortion effect apparatus.

Explanation of symbols

1 Distortion effect device 11 DSP
20 Pre-processing unit 22 Pre-filter 24 Multiplier 30 Clip processing unit (distortion applying means)
50 Effect imparting unit 62 Level detecting unit (level detecting means)
70 Control unit (control means)
100 Prefilter A
102 Multiplier A
104 Prefilter B
106 Multiplier B
108 Premixer (mixing means)
120 Effect processing means A
122 Effect processing means B
124 effect mixer

Claims (7)

An input means for inputting a musical sound signal;
A pre-processing unit for imparting frequency characteristics and gain to the musical sound signal input to the input means;
Level detection means for detecting the level of a musical sound signal between the input means and the output of the preprocessing unit;
Control means for controlling the frequency characteristics and gain imparted by the preprocessing unit according to the level detected by the level detection means;
A distortion effect device comprising distortion imparting means for imparting distortion to the musical sound signal output from the preprocessing unit.   The pre-processing unit includes a first processing unit that applies a first frequency characteristic and a first gain to the musical sound signal input to the input unit, and the first musical signal input to the input unit. Second processing means for providing a second frequency characteristic different from the first frequency characteristic and a second gain different from the first gain, an output of the first processing means, and the second processing means The mixing means for mixing the output of the control means, and the control means controls the mixing ratio of the mixing means in accordance with the level detected by the level detecting means. The distortion effect apparatus as described.   The distortion effect device according to claim 1 or 2, wherein the level detection means detects a level of a musical sound signal output from the preprocessing unit.   An effect imparting unit that imparts an effect to the musical sound signal that has been distorted by the distortion imparting unit, and the control unit further provides an effect imparted by the effect imparting unit according to the level detected by the level detecting unit The distortion effect device according to any one of claims 1 to 3, wherein the distortion effect device is controlled. An input means for inputting a musical sound signal;
A pre-processing unit for imparting frequency characteristics to the musical sound signal input to the input means;
Distortion applying means for applying distortion to the musical sound signal output from the preprocessing unit;
An effect applying unit that applies an effect to the musical sound signal that is distorted by the distortion applying means;
Level detection means for detecting the level of a musical sound signal between the input means and the output of the preprocessing unit;
Distortion effect characterized by comprising control means for controlling the frequency characteristic provided by the preprocessing unit and the mode of the effect provided by the effect applying unit according to the level detected by the level detecting unit apparatus.   The pre-processing unit is different from the first frequency characteristic for the musical sound signal input to the input means and the first processing means for imparting the first frequency characteristic to the musical sound signal input to the input means. A second processing unit that imparts a second frequency characteristic; and a mixing unit that mixes the output of the first processing unit and the output of the second processing unit. 6. The distortion effect device according to claim 5, wherein the mixing ratio of the mixing means is controlled in accordance with the level detected by the means. The effect imparting unit includes a first effect processing unit that imparts a first effect and a second effect processing unit that imparts a second effect different from the first effect,
The control means includes a first effect provided by the first effect processing means and a second effect provided by the second effect processing means according to the level detected by the detection means. The distortion effect device according to any one of claims 4 to 6, wherein the ratio is controlled.

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