JPS6082000A - Distortion composing device - Google Patents

Abstract

PURPOSE:To enable increase, decrease and change of output distortion of an actuator by composing a signal corresponding to harmonic wave of lower order from an input signal and selecting amplitude and phase of a signal for eliminating distortion for the composite signal properly. CONSTITUTION:Specified frequency component is taken out from an input signal Ei such as music and supplied to a composing circuit 200. The circuit 200 generates a composite signal having amplitude component corresponding to amplitude of extracted signal from a BPF20 and frequency component corresponding to lower order harmonic wave of the extracted signal. On the other hand, a mixing circuit 100 mixes specified part of the input signal Ei and generated composite signal at specified amplitude ratio and specified phase relation and obtains an output signal Eo.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a device for decreasing, increasing, or changing nonlinear distortion of an actuator that converts an electrical signal input into a mechanical vibration output. In particular, when the actuator is a so-called loudspeaker force, the second . The present invention relates to a distortion synthesis device that reduces third harmonic distortion and the like.

[Technical background]

A representative example of an actuator in which it is desired that the mechanical vibration output is accurately proportional to the electrical input is, for example, a speaker for playing music.

Regardless of the type of operation principle, such as electrostatic or electromagnetic, the mechanical output in response to the electrical input (
It has considerable non-linearity with respect to sound pressure). Due to this non-linearity, the output sound pressure from the power source includes high-order harmonic distortion. The main types of high-order harmonic distortion include second-order harmonic distortion (second-order HD) and third-order harmonic distortion (third-order T(I)). In general, these harmonic distortions increase as the output sound pressure of a speaker increases and as its vibration frequency decreases. Motion feedback (MFB) is known as a means for reducing such outer cloth. However, it is extremely difficult to apply a large amount of MFB stably, and there are only a few examples of industrial products that have successfully achieved low distortion using ■゛B.

Furthermore, in special cases, it may be necessary to increase the nonlinear distortion of the mechanical vibration output with respect to the electrical input, or to change its distortion component. An example of an actuator that can meet such demands is a musical instrument speaker.

In conventional electronic musical instruments, the sound from the speaker is distorted by adding a desired distortion component to the fundamental wave component of the electrical signal input to the speaker, and the nonlinear distortion of the speaker itself is electrically controlled. As far as the applicant knows, the concept of creating sounds has not been conventionally known.

〔the purpose〕

An object of the present invention is to provide a stone distortion synthesis device that can reduce, increase, or change the nonlinear distortion of an actuator for electrical/mechanical vibration conversion such as a speaker by electrical processing.

〔overview〕

In order to achieve the above-mentioned object, the present invention provides, for example, 45 to 9% of the nonlinear distortion of the sound pressure generated by the force in response to an electrical signal input of 30 Hz to 15 kT (z).
2nd order HD for 0 Hz fundamental and 30-60
Consider the case of canceling the third-order HD with respect to the Hz fundamental wave.

First, from an input signal of 30T (z ~ 15”k'Hz),
Signal components between 0 and 180 Hz are extracted using a filter. Next, this extracted signal component is frequency-divided by 1/2 and 1/3 to convert it into a 45-90 Hz signal and a 30-601 Hz signal. In this case, the input signal (301(z~1
Some signals (90-180) (5 kHz) (z
) corresponds to the second harmonic component for the 1/2 frequency-divided signal (45 to 90 Hz), and corresponds to the second harmonic component for the 1/3 frequency-divided signal (30 to 6 Hz).
For 0 T(z), it corresponds to the third harmonic component.

The secondary HD generated by the speaker when a 1/2 frequency divided signal (45 to 90Hz) is input is a part of the input signal (90Hz).
If the amplitude and phase of ~1-80)tz) are appropriately selected and inputted to the speaker, this can be canceled out. Also, 1/
Tertiary HD generates a signal when a signal divided by 3 (30 to 60 Hz) is input.
This can be canceled by appropriately selecting the amplitude and phase of 180 Hz) and inputting them directly.

In the above example, two types of low-order harmonic signals (1/2 and 1/3 frequency-divided signals) are synthesized from one type of extracted signal, and a signal is generated by these low-order harmonic signals. secondary or tertiary
Next HD is canceled using part of the input signal. By slightly modifying this perspective of distortion cancellation, the following can be achieved with 9!17i. Now, create a 1/3 frequency divided signal of 90 to 180 T (z extraction signal 75 S (30 to 60 H2),
This 1/3 frequency-divided signal is doubled to create a 60-120 Hz signal (2A frequency-divided signal for the extracted signal). Then, the secondary HD that is generated by the speaker when the 1/3 frequency divided signal (30 to 60 Hz) is input is generated by using the 27 frequency divided signal or a part of the input signal (60 to 12 (Hz)). The third-order HD of this speaker can be canceled using the extracted signal or the input signal (90 to 180 Hz).

〔Effect of the invention〕

The feature of this invention is that a harmonic signal for distortion cancellation is synthesized from the original input signal to the actuator (speaker, etc.). However, the harmonic distortion generated by the actuator due to this synthesized low-order harmonic component is canceled out by the original input signal component. In other words, since the distortion canceling signal corresponds to the original input signal itself, the actuator will not output extra high-order harmonic components that are not in the original input signal because the distortion canceling signal is input to the actuator. do not have.

In addition, in this invention, by appropriately selecting the amplitude and phase of the distortion canceling signal (a part of the input signal) for the composite low-order harmonic signal, the output distortion of the check can be increased. It is possible to change the distortion components.

[Example 1] r' Figure 1 shows 45 to 9 Q I (2 for z signal
Next T(D cancellation signal and 3 for 30-60 Hz signal
An example of a distortion synthesis system that creates the following un= and cancellation signals is shown below. Now, assume that a music signal with a frequency bandwidth of 30 Hz to 15 kHz is obtained from a Teso recorder or the like (not shown). This music signal is passed through a bypass filter (HpF,
), entered in J o.

The HPF 70 inputs the input signal E (90 of which) (z~15
Passes kHz frequency components. The output signal EIO of the HPF 10 is input to an equalizer (EQ) 12. F and Q12 have predetermined frequency characteristics determined according to the room acoustic characteristics (frequency characteristics, etc.) of a speaker system (actuator) used together with the device of the present invention. EQ12
The output signal E12 is input to the phase shifter 1'4. Phase shifter 14 appropriately shifts the phase of signal E12.

The output signal E14 of the phase shifter 14 is input to the coefficient multiplier 16. The coefficient multiplier 16 changes the amplitude of the signal E14 into a coefficient by one minute. This coefficient multiplier can be composed of an attenuator or an amplifier. The adder 18 of the coefficient unit 16 adds the signal F, 16 to a composite signal E4θ, which will be described later, to obtain an output signal E. Output. This signal E. For example, the signal is sent to a speaker system via a power amplifier (not shown). This speaker system is driven mainly by the composite signal E, 40 for signal components of 90 Hz or less, and driven mainly by the signal E16 for signal components from 90 Hz to 151<)Tz.

The secondary HD and tertiary HD generated by the speaker by the signal E40 of 90 Hz or less are included in the signal E16 and have negative phase signal components (90 to 180 T(z
) is canceled out.

Elements 10-18 receive input signals E1. A predetermined portion (90~
180 Hz) and a composite signal E40 with a predetermined amplitude ratio and a predetermined phase relationship to produce an output signal E. A mixing circuit 100 is configured to provide the following.

The input signal E7 is input to a noise filter (BPF) having a bandwidth fb of approximately 90 to 180 Hz.

The BPF 20 extracts a predetermined frequency component (9
0 to 1.80 Hz) and extract the extracted signal E20.
Output. The extracted signal E20 is input to the zero cross sensor 22. This sensor 22 can be constructed from an analog OP amplifier or the like. The sensor 22 receives the extraction signal E20,
It is converted into a rectangular signal E22 whose level is inverted at ground potential. This signal TF, 22 is converted by a waveform shaper 24 into a constant amplitude rectangular wave signal F, 24 with fast rise/fall. This shaper 24 can be constructed from a Schmitt circuit or the like. The signal E24 is divided into 4 by the 1/2 frequency divider 26.
1/2 frequency divided signal 'f with frequency components from 5 to 90 Hz
F, converted to 26. This branching unit 26 can be constructed from a TW clip frozzo or the like.

The 1/2 frequency divided signal E26 (rectangular wave) is converted by the waveform converter 28 into a constant amplitude sine wave signal E2B. Various configurations can be considered for performing this rectangular wave/sine wave conversion. −
For example, force it as follows. First, the signal E26 is integrated using a mirror integrator or the like and converted into a triangular wave. This triangular wave is converted into a digital signal X by a converter.

Using this signal X as address data, f(x)=sl
The data corresponding to n x is being input to the written ROM. This ROM acts as a code controller that converts a linear function to a sine function. The sine wave data (digital) read from this ROM is converted into a sine wave signal E28 via a D/A converter and a suitable loaf filter. The triangular wave may be converted into a sine wave by a tangent approximation method used in a function generator or the like.

The constant amplitude sinusoidal signal F, 2B is applied to a voltage controlled amplifier (vC
A) It is input at 30. The VCA 30 has an extraction signal E.
A gain control signal E60 having a DC potential corresponding to or proportional to the amplitude of 2θ is input. VCA 30 amplifies signal E2B with a gain depending on control signal E60. In other words, the constant amplitude signal E2B is amplitude-modulated by the signal 'fF,60 corresponding to or proportional to the amplitude of the extracted signal E20. VCA 30 is described, for example, in United States Patent Publication (USP) No. 3.7'25,800 (197
It can be configured using the AGC network disclosed in April 3, 2013). In this way, a signal E30 is obtained which has an amplitude component similar to that of the extracted signal E20 and a frequency component (45 to 90 Hz) that is 1/2 that of the extracted signal E20. In this way, from a sine wave signal E20 of a certain frequency (90 to 180 Hz), a sine wave signal E of a lower frequency (45 to 90 Hz) having an amplitude component corresponding to this signal is generated.
Details of the technology for synthesizing 30 are available in Japanese Patent Application No. 58-45193.
(filed on March 17, 1988), so those interested should also refer to this patent application.

Output signal E30 of VCA 30 is input to phase shifter 32. Phase shifter 32 appropriately shifts the phase of signal 'B30. The output signal E 32 f of the phase shifter 32 is applied to the first terminal of the phase inversion switch 34 . Signal E32 is still converted by phase inverter 36 into an anti-phase signal E36. Reversal jA1 precept can be done. The negative phase signal E36 is applied to the second terminal of the switch 34. The switch 34 outputs the signal B
32'l or signal B36 is selected and sent to the coefficient unit 38. The coefficient unit 38 receives the input signal (E32 or E36
) is changed by 2 minutes to the coefficient. The output signal E 3B of the coefficient multiplier 38 is input to the adder 40 .

The rectangular wave signal E24 from the waveform shaper 24 is converted into an IA signal having a frequency component of 30 to 60H2 by the 1/3 frequency divider 42.
It is converted into a frequency-divided signal E42.

The frequency divider 42 can be composed of a ternary ring counter or the like. The 1/3 frequency divided signal E42 (rectangular wave) is sent to the waveform converter 44.
It is converted into a constant amplitude sine wave signal E44. The sine wave signal E44 is input to vCA46. VCA d
6, a gain control signal E60 is input. VCA
46 has an amplitude component corresponding to the extracted signal E20 and a frequency component (30 to 60
TTz) and outputs a signal l846. Waveform converter 44 and VCA 46 are similar to waveform converter 28 described above.
and VCA 30 may be used.

Output signal E46 of VCA 46 is input to phase shifter 48. Phase shifter 48 appropriately shifts the phase of signal E46. The output signal E4s of the shifter 48 (is applied to the first terminal of the dz phase inverting switch 50. The signal B4B is also converted by the phase inverter 52 into a negative phase signal E52.

The inverter 52 may be an analog inverter with a gain of -1. The reverse phase signal E52 is applied to the second terminal of the switch 50. The switch 50 outputs a signal '? , 48 Kiteba Signal E
52 and send it to the coefficient unit 54. The coefficient unit 54 is
The amplitude of the input signal (848 or E52) is changed by a factor of 3.

The output signal F, 54 of the coefficient multiplier 54 is input to the adder 40. This adder 40 receives the signal BJ8 from the coefficient unit 38.
(45 to 90Hz) and the signal g54 (3
0 to 60) (z)
is given to the adder 18.

Elements 22 to 54 are composite signals having amplitude components corresponding to the amplitude of the extracted signal E20 and frequency components corresponding to the lower harmonics (here, 1/2 and 1/3) of the extracted signal 'E and 20. A synthesis circuit 200 that produces E40 is configured.

Extracted signal E20 from BPF 20 is input to phase shifters 56 and 5B. The amount of negative phase of the phase shifters 56 and 58 is set so that the phase difference between the output signals E56 and E5B is approximately 90 degrees, for example. In this case, signal E5
6 becomes As stone ωt, and the signal E5B becomes Acos ωt (A indicates amplitude and ω indicates angular frequency). Signal E5
6 and E5g are input to an AC/bC converter 60. The converter outputs a DC signal corresponding to or proportional to the sum of the squares of the two input signals as a gain control signal E60. In other words, E6θ−E56” +E5B”−=A2sI
n2ωt + A2cos2ωt = A or F,
60=E 562+ E 5 g2' = A". This signal A or A2 corresponds only to the amplitude component of the extracted signal g20 and indicates a DC component that does not depend on its frequency component. Therefore, VCA 3 o , 46 is a control signal E corresponding only to the amplitude component of the extracted signal E20.
60 applies amplitude modulation to the constant amplitude sinusoidal signal E28°E44.

The configuration of the force elements 56 to 60 is as per the PCT application.
It may also be configured with a vector synthesis circuit child control signal generation circuit as shown in FIGS. 2, 15, and 16 of No./7810 OO40.

For this configuration (56 to 60), a normal detection rectifier circuit + eliminator circuit (LPF) can also be used.

In Fig. 1, the signal E38 (45~90Hz) generates a secondary T(D(90~180H2)
) is part of the signal EJ6 (90-15kHz) (
90 to 180 Hz). To achieve this secondary HD cancellation, 90% of the signal E16 must be
-18011z component and the amplitude of the speaker's secondary HD component caused by the signal E3B are in one-to-one correspondence, and the phase of the 90 to 180 Hz component in the signal E16 and the speaker's secondary HD component are in a one-to-one correspondence. The phase must be adjusted to be in opposite phase. Among the adjustments, amplitude adjustment can be performed by coefficient multipliers 16 and 38, and phase adjustment can be performed by phase shifters 14 and 32. In addition, switch 3
By the operation 4, the distortion canceling operation can be switched to the distortion adding operation. Further, by shifting the amplitude adjustment and phase adjustment described above from the distortion cancellation point, it is possible to electrically change the distortion component of the sound pressure emitted from the force. Similarly, cancellation and addition of tertiary HD.

Changes can also be made by operating the coefficient multiplier 16.54, the phase shifter 14.48 and the switch 50.

In addition, in the configuration of FIG. 1, even if elements 10 to 16 are omitted and 7'', 1=B16, a practical distortion synthesis device can be obtained. Of course, it is also possible to omit the HPF 10. In addition, the HPF 10 may be a BPF' having a desired passband width depending on the case.

Alternatively, a band rejection filter (BRF) that cuts specific frequency components may be used.

[Embodiment 2] FIG. 2 shows an example of a distortion synthesizer that produces a secondary HD cancellation signal for a 45-90 Hz signal and a secondary (D) cancellation signal for a 30-60 Hz signal.Input signal'
Ei (60 to 15 of 30 to 15 kT(z)
k) Tz component is HPF1θ, EQ12° phase shifter 1
4 and the coefficient unit 16 to the adder 18 . Of the input signal Ei, the extracted signal E20 corresponding to the 90 to 180 Hz component is input to the zero cross sensor 22 via the BPF 20. This signal E20 has elements 22, 24° 26.2B, 3θ, 32, 34, 36.3
8+56.58.60, it is converted into a composite signal g3B of 45 to 90H3. These elements (22 to 6 (1
1) may be equivalent to the corresponding element in FIG. Of the input signal Ei, the extracted signal E21 corresponding to the 60 to 120 Hz component is input to the zero cross sensor 23 via the BPF,'1.

This signal F221 has elements 2.9 and 25.27.

44.46.4B, 50, 52, 54, 57°59.6
1, it is converted into a composite signal E54 of 30 to 60H2. Elements 23, 25.27157.59.61 can be constructed similarly to elements 22.24.26.56.58.60, respectively. Also, elements 44-54 may be equivalent to the corresponding elements in FIG.

The composite signal E 3 B (45-90 H2) and the composite signal E s 4 (30-60 Hz) are sent to the adder 4.
0 and the composite signal E40 (30 to 90
Hz) Totoru. This signal E40 is added to the signal EJ6 (60-15k)lz) in the adder 18, and the output signal E is obtained. (30-151c)Tz). here,
The loudspeaker secondary HD due to signal F, 54 (30-60'Hz) can be canceled by the 60-120 Hz component in signal EIG.

The adjustment for this cancellation is the factor 14 + 16 + 48 +
50.54. Signal E 3 B
(The second-order HD due to
,? 2, 34, . 9 B allows you to move left. Elements 14.16, 32, 34 not only cancel the distortion, but also change the distortion components and increase the distortion.
, 38.4B, 50°54 (in some cases 10,12
, 21 and 22)).

In the configuration shown in FIG. 2, if elements 26 and 27 are combined with an extra-1 counter (IAJ frequency divider), it is possible to cancel, change, or increase the N-order HD.

[Actual Buoy α Example 3] Figure 3 shows the secondary and 3rd order signals for a 30-60 Hz signal.
An example of a distortion synthesis device that produces an HD cancellation signal is shown below.

Of the input signals E7 (30 to 15 kHz), 12
0 to 15 kT (the component of z is I(PF 10 ).

EQ12. The signal is input to the adder 72 via the phase shifter 14 and the coefficient unit 16. 60 to 15 of the input signals Ei
The components of kI(z (60 to 120 Hz) are T(PF(BPF) 11 , EQ 13 ).

Phase shifter 15. The extracted signal E2o corresponding to the 90 to 180 Hz component of the adder input signal E4 is inputted to the zero cross sensor 22 via the BPF"2θ through the + and coefficient unit 17. This signal E20 is Sensor 22.
It is converted into an IA frequency divided signal E42 (30 to 60 Hz) via the waveform shaper 24 and IA frequency divider 42. This signal E42 is a double-multiplying signal E7+7. (60-120Hz). This doubler circuit 7θ is manufactured by patent application No. 58-4, 51
Figure 1 of issue 93 is still EXO as shown in Figure 4.
A circuit using R or Ryohatome flow may also be used. This signal E
70 is the element 28*30°32 , 34 , 36 , .
9B, 60~120T (z composite signal E3B
is converted to These elements (28-38) may be equivalent to the corresponding elements in FIG. 1/3 frequency division signal E42
is converted into a signal E54 of 30 to 60j (z) via elements 44.46.4B, 50, and 52.54.These elements (44 to 54) are also equivalent to the corresponding elements in FIG. Anything is fine.

The adder 72 receives the output signal E16 (120~
15kHz) and composite signal E38 (60-120Hz
) is applied to the adder 1J and a signal E72 (60 to 15 kHz). Further, the adder 74 includes the coefficient unit 1
7 output signal EI7 (60~15 kHz i is 60
~120Hz) and composite signal E54 (30~60Hz
) and signal E74 (30 to 15 kT (z or 3
0 to 120 Hz) to the adder 76. Then, the adder 76 outputs an output signal E corresponding to the sum of the signal B72 and the signal E74. (30~l5k)Tz) is output.

As described above, this invention can be realized by various embodiments. It is free to choose which of the embodiments and other embodiments described above to carry out this invention within the spirit of this invention.

In addition to speakers, the present invention can also be applied to cutter heads for records, vibrators for vibration tests, ultrasonic vibrators used for diagnosis, flaw detection, etc. Furthermore, speakers are not limited to full-range types or woofers, but can also be used for squawkers, tweeters, and the like. In particular, when this invention is applied to squawkers, tweeters, or full-range speakers, in addition to canceling high-order harmonic distortion, changing distortion components or adding distortion is also effective in controlling timbre. .

Each of the distortion synthesis devices shown in FIGS. 1 to 3 may be formed into a unit, and a plurality of distortion synthesis units may be used together (connected in series/parallel). For example, 100 in the first unit.
Distortion (overtone components) may be added to the high frequency range of 4 kHz or higher by the unit for the low frequency range of Hz or lower.

This invention is particularly effective for canceling nonlinear distortion in actuators, but it can also be used to cancel, increase, or change distortion not only in actuators but also in recording/playback systems such as tape recorders, electric circuits, etc.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing nine components of a distortion synthesizer according to an embodiment of the present invention; FIG. 2 is a block diagram showing another embodiment of the invention; FIG. 3 is a block diagram showing still another embodiment of the invention. FIG. 2 is a block diagram showing an example. 10.11...Hinogus Filter;, 1-2.13
... Equalizer: 14.15, 32.4B, se~5
9... Phase shifter'', 16.17.38.54... Coefficient unit', Ig, 40,72,74.76... Adder; 2
0.21... Pantone gas filter; 22, 23...
・Zero cross sensor:, 94. ,? 5... Waveform shaper: 26.27, 42... Frequency divider", 28.44...
Waveform converter', 30.46...voltage control amplifier; 34
゜50...Phase inversion switch; s6. s2... Phase inverter; "+61... AC Oki C converter -70...
Double multiplier circuit: 100...mixing circuit; 200...combining circuit; Ei...input signal; Eo output signal", B20.
B21...extracted signal; EJ8, B40,
E54910 composite signal: B60, B61...
・Gain control signal.

Claims (1)

[Scope of Claims] A filter that extracts a predetermined frequency component from an input signal and provides an extracted signal; and 1. A filter that is coupled to the filter and that extracts a predetermined frequency component from an input signal and provides an extracted signal with an amplitude component corresponding to the amplitude of the extracted signal and a lower harmonic of the extracted signal. a combining circuit that produces a combined signal having corresponding frequency components; and a combining circuit that is coupled to the combining circuit and mixes a predetermined portion of the input signal and the combined signal with a predetermined amplitude ratio and a predetermined phase relationship to produce an output signal. Distortion synthesis circuit with mixing circuit currently available.