JPH05191885A - Acoustic signal equalizer circuit - Google Patents

Acoustic signal equalizer circuit

Info

Publication number
JPH05191885A
JPH05191885A JP4022026A JP2202692A JPH05191885A JP H05191885 A JPH05191885 A JP H05191885A JP 4022026 A JP4022026 A JP 4022026A JP 2202692 A JP2202692 A JP 2202692A JP H05191885 A JPH05191885 A JP H05191885A
Authority
JP
Japan
Prior art keywords
signal
amplitude
frequency component
component
frequency
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
JP4022026A
Other languages
Japanese (ja)
Inventor
Haruo Sakata
晴夫 坂田
Original Assignee
Clarion Co Ltd
クラリオン株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Clarion Co Ltd, クラリオン株式会社 filed Critical Clarion Co Ltd
Priority to JP4022026A priority Critical patent/JPH05191885A/en
Priority claimed from US07/993,389 external-priority patent/US5388159A/en
Publication of JPH05191885A publication Critical patent/JPH05191885A/en
Granted legal-status Critical Current

Links

Abstract

PURPOSE:To reproduce sound quality rich in auditory sensation by adding a high frequency component in an audible band at the time of reproducing an acoustic signal restricted in the band. CONSTITUTION:Respective high frequency component signals EH1 to EH4 to be outputted from a component wave device 2 are added to envelope detectors 11-1 to 11-4 and square circuits 8-1 to 8-4. Higher harmonic component signals from the square circuits 8-1 to 8-4 are inputted to gain control circuits 10-1 to 10-4 via BPFs 9-1 to 9-4. Respective amplitude modulation signals which was modulated in amplitude by amplitude detection signals from the envelope detectors 11-1 to 11-4 and controlled in gain via attenuators 14-1 to 14-4 are fed to an addition circuits 11. The addition circuit 11 synthsizes the respective amplitude modulation signals with a low frequency component signal from the component wave device 2 and feds the synthesized signal to a switch 15.

Description

【発明の詳細な説明】Detailed Description of the Invention
【0001】[0001]
【産業上の利用分野】本発明は帯域制限されたオーディ
オ信号の再生に際して聴感に対して豊かな音の再現を可
能とするための音響信号イコライザ回路に関する。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an acoustic signal equalizer circuit for reproducing a sound rich in hearing when reproducing a band-limited audio signal.
【0002】[0002]
【従来の技術】音響信号の伝送記録については、適合す
る帯域があり、例えば、FM放送では0〜15kHz、C
Dでは0〜20kHzが好適な伝送帯域である。この伝送
帯域の上限周波数をfCとすると、これはfCをカットオ
フ周波数とする一種のローパスフィルタ(LPF)と見
ることができ、音源の周波数が図2(a)に示すように
C以下の場合には上記ローパスフィルタ(LPF)を
介してもそのまま記録又は伝送されるので問題はない。
2. Description of the Related Art There is a suitable band for transmission and recording of acoustic signals, for example, 0 to 15 kHz, C for FM broadcasting.
In D, 0 to 20 kHz is a suitable transmission band. When the upper limit frequency of the transmission band and f C, which can be seen as a kind of low-pass filter (LPF) to cut-off frequency f C, f C such that the frequency of the sound source is shown in FIG. 2 (a) In the following cases, there is no problem because the data is recorded or transmitted as it is even through the low pass filter (LPF).
【0003】ところが図2(b)に示すように音源にf
C以上の成分がある場合にはfC以上の成分が上記ローパ
スフィルタ(LPF)で除去されて伝送又は記録されて
図2(c)のようになるので、当然fC以上の成分は再
生されずに原音とは異なった音が再生される。
However, as shown in FIG. 2B, the sound source f
When there is a component of C or more, the component of f C or more is removed by the low-pass filter (LPF) and is transmitted or recorded to be as shown in FIG. 2C, so that the component of f C or more is reproduced. Instead, a sound different from the original sound is played.
【0004】昨今のように収音技術がすぐれ、再生機器
の性能が向上すると、FMでの15kHz以上の成分、C
Dでの20kHz以上の成分を除去してしまうと、音質の
劣化と感じる場合がある。一般に可聴音は20Hz〜20
kHzと言われているが、20kHzで感度が0になる訳で
はない。
When the sound collecting technology is improved and the performance of the reproducing apparatus is improved as in recent years, the component of 15 kHz or more in FM, C
If the component of 20 kHz or more in D is removed, the sound quality may be deteriorated. Generally, audible sound is 20Hz-20
It is said to be kHz, but the sensitivity does not become zero at 20 kHz.
【0005】[0005]
【発明が解決しようとする課題】従来は上述した伝送系
の帯域制限下での音響信号の再現を目標としていた。し
かし図2(a)に示す如く原音源がfAの周波数分布を
とるものとすると、前述のように伝送系や記録系にはそ
の伝送帯域に制限があるため、音響信号はfCのカット
オフ周波数のローパスフィルタを通すことになり、fA
>fCの信号は削除されてしまう。その結果、再生系で
忠実に再生したとしてもfA>fCの成分は再生できず、
忠実再生と言う観点から問題である。
In the past, the aim was to reproduce the acoustic signal under the band limitation of the transmission system described above. However, assuming that the original sound source has a frequency distribution of f A as shown in FIG. 2A, the acoustic signal is cut at f C because the transmission system and the recording system have a limited transmission band as described above. It will be passed through an off-frequency low-pass filter, and f A
The signal with> f C is deleted. As a result, even if the reproduction system faithfully reproduces, the component of f A > f C cannot be reproduced,
This is a problem from the perspective of faithful reproduction.
【0006】即ち、削除されてしまうfA>fCの帯域に
は、豊かな高域音を発生させる周波数成分が含まれてい
るので、従来のようにLPFと等価な伝送系でこの成分
をカットしてしまうのでは、原音の忠実な再生は不可能
で音質が劣化する問題がある。
That is, since the band of f A > f C that is deleted contains a frequency component that generates rich high frequency sound, this component is used in a transmission system equivalent to the LPF as in the conventional case. If it is cut, the original sound cannot be reproduced faithfully and the sound quality deteriorates.
【0007】本発明の目的は帯域制限された音響信号の
再生に際し、伝送系で削除された可聴域の高周波成分を
付加できるモード機能を設けて、必要に応じてこのモー
ド機能を作用させて豊かな再生音響を得ることを可能と
するための音響信号イコライザ回路を提案することにあ
る。
An object of the present invention is to provide a mode function capable of adding a high frequency component in the audible range deleted in the transmission system when reproducing a band-limited acoustic signal, and to make the mode function act as necessary to enhance the function. The purpose is to propose an audio signal equalizer circuit that enables to obtain various reproduced sounds.
【0008】[0008]
【課題を解決するための手段】上記目的を達成するた
め、本願の第1の発明の音響信号イコライザ回路は、音
響信号を、所定カットオフ周波数以下の低周波成分信号
と、該カットオフ周波数以上で複数の異なる周波数帯域
に分割された複数の高周波成分信号と、に分離する周波
数成分分離手段と、前記各高周波成分信号を振幅検波し
て検波信号を得る振幅検波手段と、前記各高周波成分信
号から夫々所定倍の高調波成分信号を抽出する高調波成
分抽出手段と、上記各高調波成分信号を前記検波信号に
より振幅変調し利得制御された夫々の振幅変調信号を得
る振幅変調手段と、上記各振幅変調信号と前記音響信号
の低周波成分信号とを合成して合成信号を得る信号合成
手段と、を有することを特徴とする。
In order to achieve the above object, an acoustic signal equalizer circuit according to a first invention of the present application provides an acoustic signal including a low frequency component signal having a predetermined cutoff frequency or lower and a cutoff frequency higher than the cutoff frequency. A plurality of high frequency component signals divided into a plurality of different frequency bands, a frequency component separating means for separating the high frequency component signals, an amplitude detecting means for amplitude detecting each high frequency component signal to obtain a detection signal, and each high frequency component signal A harmonic component extracting means for extracting a harmonic component signal of a predetermined multiple from each of them, and an amplitude modulating means for amplitude-modulating each of the harmonic component signals by the detection signal to obtain each gain-controlled amplitude modulated signal; Signal synthesizing means for synthesizing each amplitude modulated signal and the low frequency component signal of the acoustic signal to obtain a synthesized signal.
【0009】また、本願の第2の発明の音響信号イコラ
イザ回路は、音響信号を、所定カットオフ周波数以下の
低周波成分信号と、該カットオフ周波数以上で複数の異
なる周波数帯域に分割された複数の高周波成分信号と、
に分離する周波数成分分離手段と、前記各高周波成分信
号を振幅検波して検波信号を得る振幅検波手段と、前記
各高周波成分信号のゼロクロス点を検出して各ゼロクロ
ス信号を出力するゼロクロス検出手段と、上記各ゼロク
ロス信号を前記検波信号により振幅変調し利得制御され
た夫々の振幅変調信号を得る振幅変調手段と、上記各振
幅変調信号と前記各高周波成分信号との各差成分信号を
抽出する差成分信号出力手段と、上記各差成分信号と前
記音響信号の低周波成分信号とを合成して合成信号を得
る信号合成手段と、を有することを特徴とする音響信号
イコライザ回路。
In the acoustic signal equalizer circuit according to the second aspect of the present invention, the acoustic signal is divided into a plurality of low frequency component signals having a predetermined cutoff frequency or less and a plurality of different frequency bands having the cutoff frequency or more. High-frequency component signal of
A frequency component separating means for separating the high frequency component signal, an amplitude detecting means for amplitude detecting the high frequency component signal to obtain a detection signal, and a zero cross detecting means for detecting a zero cross point of the high frequency component signal and outputting a zero cross signal. , An amplitude modulation means for amplitude-modulating each of the zero-cross signals by the detection signal to obtain each amplitude-controlled amplitude-controlled signal, and a difference for extracting each difference component signal between each of the amplitude modulation signals and each of the high-frequency component signals. An acoustic signal equalizer circuit comprising: a component signal output means; and a signal synthesizing means for synthesizing each of the difference component signals and a low frequency component signal of the acoustic signal to obtain a synthesized signal.
【0010】更に本願の第3の発明の音響信号イコライ
ザ回路は、音響信号を、所定カットオフ周波数以下の低
周波成分信号と、該カットオフ周波数以上で複数の異な
る周波数帯域に分割された複数の高周波成分信号と、に
分離する周波数成分分離手段と、前記各高周波成分信号
を振幅検波して検波信号を得る振幅検波手段と、前記各
周波成分信号のゼロクロス点を検出して各ゼロクロス信
号を出力するゼロクロス検出手段と、上記各ゼロクロス
信号を前記検波信号により振幅変調し利得制御された夫
々の振幅変調信号を得る振幅変調手段と、上記各振幅変
調信号と前記各周波成分信号との各和成分信号を抽出す
る和成分信号出力手段と、上記各和成分信号と前記音響
信号の低周波成分信号とを合成して合成信号を得る信号
合成手段と、を有することを特徴とする。
Further, in the acoustic signal equalizer circuit of the third invention of the present application, the acoustic signal is divided into a low frequency component signal having a predetermined cutoff frequency or less and a plurality of different frequency bands above the cutoff frequency. A high-frequency component signal, a frequency component separation means for separating the high-frequency component signal, an amplitude detection means for amplitude-detecting each high-frequency component signal to obtain a detection signal, and a zero-cross point of each frequency component signal to output each zero-cross signal Zero-cross detection means, an amplitude modulation means for amplitude-modulating each of the zero-cross signals by the detection signal to obtain a gain-controlled amplitude-modulated signal, and each sum component of each of the amplitude-modulated signals and each of the frequency-component signals A sum component signal output means for extracting a signal, and a signal synthesizing means for synthesizing each sum component signal and the low frequency component signal of the acoustic signal to obtain a synthesized signal. And wherein the Rukoto.
【0011】なお、本願の第4の発明の音響信号イコラ
イザ回路は、前記第1、第2又は第3の発明の回路にお
いて、前記合成信号と前記音響信号とのいずれかを選択
して出力する選択出力手段を有することを特徴とする。
The acoustic signal equalizer circuit of the fourth invention of the present application selects and outputs either the synthesized signal or the acoustic signal in the circuit of the first, second or third invention. It is characterized by having a selection output means.
【0012】[0012]
【作用】第1の発明の回路において、音響信号は低周波
数成分信号と、複数の異なる周波数帯域に分割された高
周波成分信号と、に分離される。各高周波成分信号は振
幅検波されて検波信号を得ると共に所定倍の各高調波成
分信号を抽出する。各高調波成分信号は上記検波信号に
より振幅変調されて得られた利得制御された各振幅変調
信号と前記低周波成分信号とが合成される。
In the circuit of the first invention, the acoustic signal is separated into the low frequency component signal and the high frequency component signal divided into a plurality of different frequency bands. Each high-frequency component signal is amplitude-detected to obtain a detection signal, and each harmonic component signal of a predetermined multiple is extracted. Each harmonic component signal is amplitude-modulated by the detected signal, and each gain-controlled amplitude-modulated signal obtained by amplitude-modulation is combined with the low-frequency component signal.
【0013】また第2の発明の回路では、前記各高周波
成分信号のゼロクロス点が検出され、得られたゼロクロ
ス信号が前記検波信号により振幅変調される。そして各
振幅変調信号と各高周波成分信号との各差成分信号と前
記低周波成分信号とが合成される。
In the circuit of the second invention, the zero-cross point of each high-frequency component signal is detected, and the obtained zero-cross signal is amplitude-modulated by the detection signal. Then, each difference component signal between each amplitude modulation signal and each high frequency component signal and the low frequency component signal are combined.
【0014】更に第3の発明の回路では、前記ゼロクロ
ス信号を振幅変調した各振幅変調信号と各高周波成分信
号との各和成分信号と前記低周波成分信号とが合成され
る。
Further, in the circuit of the third invention, the sum component signal of each amplitude modulation signal obtained by amplitude-modulating the zero cross signal and each high frequency component signal and the low frequency component signal are combined.
【0015】なお、第4の発明の回路によると、前記各
回路で、合成信号と音響信号とを、任意に選択して出力
することができる。
According to the circuit of the fourth aspect of the present invention, in each of the circuits, the composite signal and the acoustic signal can be arbitrarily selected and output.
【0016】[0016]
【実施例】以下図面に示す本発明の各実施例を説明す
る。図1は第1の発明による音響信号イコライザ回路の
一実施例である。同図において、1は帯域制限された音
響信号、2は分波器で、前記周波数成分分離手段に相当
する。分波器2は、例えば、カットオフ周波数fLの1
個のローパスフィルタと、センター周波数がfL以上の
H1,fH2,fH3,fH4の4チャンネルの狭帯域バンド
パスフィルタとから成るものとし、3は低周波成分信号
Lの出力端子、4〜7は各高周波成分信号EH1〜EH4
の出力端子である。8−1〜8−4は2乗回路及び9−
1〜9−4は中心周波数が2fH1〜2fH4のバンドパス
フィルタで、前記高調波成分抽出手段を構成する。
Embodiments of the present invention shown in the drawings will be described below. FIG. 1 shows an embodiment of an acoustic signal equalizer circuit according to the first invention. In the figure, reference numeral 1 is a band-limited acoustic signal, and 2 is a demultiplexer, which corresponds to the frequency component separating means. The duplexer 2 has, for example, a cutoff frequency f L of 1
4 low-pass filters and a 4-channel narrow-band band-pass filter of f H1 , f H2 , f H3 , and f H4 whose center frequency is f L or more, and 3 is an output terminal of the low frequency component signal E L. 4 to 7 are high frequency component signals E H1 to E H4
Output terminal of. 8-1 to 8-4 are squaring circuits and 9-
Reference numerals 1 to 9-4 are bandpass filters having a center frequency of 2f H1 to 2f H4 and constitute the harmonic component extracting means.
【0017】10−1〜10−4は利得制御回路(又は
振幅変調回路)で、前記振幅変調手段を構成する。11
−1〜11−4はエンベロープ検波器で、前記振幅検波
手段を構成する。12は加算回路で、前記信号合成手段
に相当する。13は出力信号、14−1〜14−4は減
衰器である。15はスイッチで、前記選択出力手段を構
成する。
Gain control circuits (or amplitude modulation circuits) 10-1 to 10-4 constitute the amplitude modulation means. 11
-1 to 11-4 are envelope detectors, which constitute the amplitude detector. Reference numeral 12 is an adder circuit, which corresponds to the signal synthesizing means. Reference numeral 13 is an output signal, and 14-1 to 14-4 are attenuators. A switch 15 constitutes the selection output means.
【0018】音響信号1は分波器2によりカットオフ周
波数fL以下の低周波成分信号ELと、チャンネルの異な
る周波数帯域の高周波成分信号EH1〜EH4と、に分離さ
れる。
The acoustic signal 1 is separated by the demultiplexer 2 into a low frequency component signal E L having a cutoff frequency f L or less and high frequency component signals E H1 to E H4 in different frequency bands of channels.
【0019】各高周波成分信号EH1〜EH4は2乗回路8
−1〜8−4及びエンベロープ検波器11−1〜11−
4に加えられ、各2乗回路の出力はバンドパスフィルタ
9−1〜9−4を介して夫々2fH1〜2fH4中心の高調
波成分信号が抽出される。
Each high-frequency component signal E H1 to E H4 is a squaring circuit 8
-1 to 8-4 and envelope detector 11-1 to 11-
4 and the output of each squaring circuit is subjected to bandpass filters 9-1 to 9-4 to extract harmonic component signals centered on 2f H1 to 2f H4, respectively .
【0020】ここで、例えば、fH1中心の高周波成分信
号EH1が EH1=e1cosωH1t (1) とすると、その2乗出力EH1 2は EH1 2=(e1 2/2)+(e1 2/2)cos2ωH1t (2)
[0020] Here, for example, if f H1 center of the high frequency component signal E H1 is E H1 = e 1 cosω H1 and t (1), the square of the output E H1 2 is E H1 2 = (e 1 2 /2 ) + (e 1 2/2 ) cos2ω H1 t (2)
【0021】(2)式の第2項の成分が前記バンドパス
フィルタを介して抽出される。図3(a)は分波器2の
出力特性、同図(b)は各バンドパスフィルタ9−1〜
9−4の各出力特性を夫々示しており、2fH1の成分を
1、2fH2の成分をa2、2fH3の成分をa3、2fH4
の成分をa4としてfL以下の成分に加えると、図3
(c)のようになり、fLのカットオフフィルタで消失
した成分が復元できる。
The component of the second term of the equation (2) is extracted via the bandpass filter. 3A shows the output characteristics of the demultiplexer 2, and FIG. 3B shows the bandpass filters 9-1 to 9-1.
9-4 shows the respective output characteristics of 9-4, where the 2f H1 component is a 1 , the 2f H2 component is a 2 , the 2f H3 component is a 3 , and the 2f H4 component is a 3 2f H4.
3 is added to the component below f L as a 4
As shown in (c), the component lost by the f L cutoff filter can be restored.
【0022】エンベロープ検波器11−1〜11−4は
各高周波成分信号EH1〜EH4の振幅を検波し、各検波信
号を利得制御回路10−1〜10−4に夫々送る。各利
得制御回路は前記各高調波成分信号を上記各検波信号に
より振幅変調してEH1〜EH4の振幅a1〜a4に比例する
ように利得制御された振幅変調信号を出力し減衰器14
−1〜14−4を介して加算回路12で低周波成分信号
Lと合成する。
The envelope detectors 11-1 to 11-4 detect the amplitudes of the high frequency component signals E H1 to E H4 , and send the detected signals to the gain control circuits 10-1 to 10-4, respectively. Each gain control circuit amplitude-modulates each harmonic component signal by each detection signal and outputs an amplitude-modulated signal whose gain is controlled so as to be proportional to the amplitudes a 1 to a 4 of E H1 to E H4 , and outputs the attenuator. 14
The addition circuit 12 synthesizes the low frequency component signal E L via -1 to 14-4.
【0023】本来、高調波歪は少ない方がよいが、図4
の聴覚の感度の説明図に示すように、聴覚は周波数f0
(1.5〜2.5kHz)以下では音の位相に対して感度
があるが、図4の実線で示すf0以上の信号に対しては
位相には不感で振幅のみに感じることが知られている。
Originally, it is better that the harmonic distortion is small.
As shown in the explanatory diagram of the auditory sensitivity of the auditory sense, the auditory sense has the frequency f 0.
It is known that at (1.5 to 2.5 kHz) or less, there is sensitivity to the phase of the sound, but for signals above f 0 shown by the solid line in FIG. 4, the phase is insensitive and only the amplitude is felt. ing.
【0024】従って図3でfC>f0ならば、fC以上の
成分は歪としては感じることなく、元の信号源、即ち、
Cで遮断する前の信号と、振幅では近くなることは図
3に示した通りである。
Therefore, if f C > f 0 in FIG. 3, the components above f C are not perceived as distortion, and the original signal source, that is,
It is as shown in FIG. 3 that the amplitude becomes closer to the signal before being cut off at f C.
【0025】なお、図1の実施例において、減衰器14
−1〜14−4の係数を零にして、高調波成分を零にす
ることは勿論可能である。更に各高周波成分信号EH1
H4と、各2乗回路の出力成分との乗算により得られた
第3高調波成分を付加することも可能である。またスイ
ッチ15を設け、加算回路11からの出力信号13(合
成信号)と、音響信号とを選択可能とすることもでき
る。
In the embodiment of FIG. 1, the attenuator 14
It is of course possible to set the coefficients of -1 to 14-4 to zero and the harmonic components to zero. Furthermore, each high frequency component signal E H1 ~
It is also possible to add the third harmonic component obtained by multiplying E H4 and the output component of each squaring circuit. Further, a switch 15 may be provided so that the output signal 13 (combined signal) from the adder circuit 11 and the acoustic signal can be selected.
【0026】図5は第2の発明による音響信号イコライ
ザ回路の一実施例で、図1と同一符号は同一又は類似の
回路をあらわし、16−1〜16−4はゼロクロス発生
器で、前記ゼロクロス検出手段を構成する。17−1〜
17−4は差動増幅器で、前記差成分信号出力手段を構
成する。
FIG. 5 shows an embodiment of an acoustic signal equalizer circuit according to the second invention. The same reference numerals as those in FIG. 1 represent the same or similar circuits, and 16-1 to 16-4 are zero-cross generators. It constitutes a detection means. 17-1 to
A differential amplifier 17-4 constitutes the difference component signal output means.
【0027】まず、分波器2からの高周波成分信号EH1
(図6(a))はゼロクロス発生器16−1に加えられ
て、0レベルでの立上り、立下りの明確な方形波のゼロ
クロス信号(図6(b))に変換される。
First, the high frequency component signal E H1 from the demultiplexer 2
(FIG. 6 (a)) is added to the zero-cross generator 16-1 and converted into a zero-cross signal (FIG. 6 (b)) having a clear square wave of rising and falling at 0 level.
【0028】また振幅検波器(エンベロープ検波器)1
1−1は図6(a)の破線で示す振幅を検波して、その
検波信号により振幅変調器10−1が上記ゼロクロス信
号を振幅変調して利得制御された図6(c)に示す波形
の振幅変調信号を得る。該振幅変調信号と前記高周波成
分信号EH1とは差動増幅器17−1に加えられ、図6
(d)に示す両信号の差成分信号を得る。前記振幅変調
信号(図6(c))は高周波成分信号EH1(図6
(a))と振幅は一致しているので、上記差成分信号で
は、基本波成分が打ち消されて高調波成分が主体となっ
ている。この差成分信号は減衰器14−1を通すことに
より上記高調波成分の調整をして加算回路11に入力さ
れる。
An amplitude detector (envelope detector) 1
Reference numeral 1-1 shows the waveform shown in FIG. 6C in which the amplitude shown by the broken line in FIG. 6A is detected and the amplitude modulator 10-1 amplitude-modulates the zero-cross signal by the detected signal to perform gain control. To obtain an amplitude modulation signal of. The amplitude modulation signal and the high frequency component signal E H1 are added to the differential amplifier 17-1,
The difference component signal of both signals shown in (d) is obtained. The amplitude modulation signal (FIG. 6C) is a high frequency component signal E H1 (FIG. 6C).
Since the amplitude is the same as that in (a)), the fundamental wave component is canceled out in the difference component signal, and the harmonic component is the main component. This difference component signal is passed through the attenuator 14-1 to adjust the above harmonic component and input to the adder circuit 11.
【0029】分波器2からの他の高周波成分信号EH2
H4に対しても同様な処理が行われ、加算回路11は各
差成分信号と低周波成分信号ELとが合成され、合成信
号(図6(e))13がスイッチ15に出力される。
Another high frequency component signal E H2 from the demultiplexer 2
Similar processing is performed on E H4 , and the addition circuit 11 combines the respective difference component signals and the low frequency component signal E L and outputs a combined signal (FIG. 6E) 13 to the switch 15. ..
【0030】図7は第3の発明による音響信号イコライ
ザ回路の一実施例で、図5と同一符号は同一又は類似の
回路をあらわし、18−1〜18−4は加算器で、前記
和成分信号出力手段を構成する。19−1a,19−1
b,19−2a,19−2b,19−3a,19−3
b,19−4a,19−4bは夫々連動した係数が
1,(1−k1),k2,(1−k2),k3,(1−
3),k4,(1−k4)の夫々1対の減衰器である。
FIG. 7 shows an embodiment of an acoustic signal equalizer circuit according to the third invention, in which the same reference numerals as those in FIG. 5 represent the same or similar circuits, and 18-1 to 18-4 are adders, which are the sum components. It constitutes a signal output means. 19-1a, 19-1
b, 19-2a, 19-2b, 19-3a, 19-3
b, 19-4a, 19-4b are coefficients k 1 were respectively linked, (1-k 1), k 2, (1-k 2), k 3, (1-
k 3 ), k 4 and (1-k 4 ) are a pair of attenuators, respectively.
【0031】前記高周波成分信号EH1はゼロクロス発生
器16−1に加えられ、例えばEH1が図8(a)の波形
であるとして同図(b)に示すゼロクロス信号を発生す
る。このゼロクロス信号は振幅変調器(又は利得制御回
路)10−1で前記振幅検波信号により振幅変調され、
振幅がEH1と等しくなるように利得制御された振幅変調
信号を出力する。この振幅変調信号及び前記高周波成分
信号EH1は夫々減衰器19−1a,19−1bを通るこ
とによりk1倍、(1−k1)倍され加算器18−1で加
算されて図8(c)の波形の和成分信号となって加算回
路11に送られる。
The high-frequency component signal E H1 is applied to the zero-cross generator 16-1, and the zero-cross signal shown in FIG. 8B is generated assuming that E H1 has the waveform shown in FIG. 8A. This zero-cross signal is amplitude-modulated by the amplitude detection signal in the amplitude modulator (or gain control circuit) 10-1,
An amplitude modulation signal whose gain is controlled so that its amplitude is equal to E H1 is output. The amplitude modulation signal and the high frequency component signal E H1 are multiplied by k 1 and (1-k 1 ) by passing through attenuators 19-1a and 19-1b, respectively, and added by an adder 18-1 to obtain the signal shown in FIG. The sum component signal of the waveform of c) is sent to the adder circuit 11.
【0032】前記高周波成分信号EH2,EH3,EH4につ
いても同様な処理が行われるが、各減衰器の係数はk1
<k2<k34に設定する。加算回路11は各和成分信
号と低周波成分信号ELを合成し、その合成信号13を
スイッチ15に出力する。
Similar processing is performed on the high frequency component signals E H2 , E H3 and E H4 , but the coefficient of each attenuator is k 1
Set <k 2 <k 3 < 4 . The adder circuit 11 synthesizes each sum component signal and the low frequency component signal E L , and outputs the synthesized signal 13 to the switch 15.
【0033】[0033]
【発明の効果】以上説明したように本発明の音響信号イ
コライザ回路によれば、帯域制限された音響信号の再生
時に帯域外の高周波成分信号を付加することにより聴感
上豊かな音質を再現することができる。
As described above, according to the acoustic signal equalizer circuit of the present invention, a high-frequency component signal outside the band is added at the time of reproducing the band-limited acoustic signal to reproduce a sound quality rich in the sense of hearing. You can
【図面の簡単な説明】[Brief description of drawings]
【図1】本願の第1の発明の一実施例を示すブロック図
である。
FIG. 1 is a block diagram showing an embodiment of a first invention of the present application.
【図2】音信号の周波数fAと伝送帯域との関係を示す
特性図である。
FIG. 2 is a characteristic diagram showing a relationship between a frequency f A of a sound signal and a transmission band.
【図3】図1の実施例の動作説明用の周波数特性図であ
る。
FIG. 3 is a frequency characteristic diagram for explaining the operation of the embodiment of FIG.
【図4】聴覚の周波数特性の説明図である。FIG. 4 is an explanatory diagram of auditory frequency characteristics.
【図5】本願の第2の発明の一実施例を示すブロック図
である。
FIG. 5 is a block diagram showing an embodiment of the second invention of the present application.
【図6】図5の実施例の動作説明用の波形図である。6 is a waveform diagram for explaining the operation of the embodiment of FIG.
【図7】本願の第3の発明の一実施例を示すブロック図
である。
FIG. 7 is a block diagram showing an embodiment of the third invention of the present application.
【図8】図7の実施例の動作説明用の波形図である。8 is a waveform diagram for explaining the operation of the embodiment of FIG.
【符号の説明】[Explanation of symbols]
1 音響信号 2 分波器 8−1〜8−4 2乗回路 10−1〜10−4 利得制御(振幅変調)回路 11−1〜11−4 エンベロープ(振幅)検波回路 12 加算回路 15 スイッチ 16−1〜16−4 差動増幅器 18−1〜18−4 加算器 1 Acoustic Signal 2 Demultiplexer 8-1 to 8-4 Square Circuit 10-1 to 10-4 Gain Control (Amplitude Modulation) Circuit 11-1 to 11-4 Envelope (Amplitude) Detection Circuit 12 Adder Circuit 15 Switch 16 -1 to 16-4 Differential amplifier 18-1 to 18-4 Adder

Claims (4)

    【特許請求の範囲】[Claims]
  1. 【請求項1】 音響信号を、所定カットオフ周波数以下
    の低周波成分信号と、該カットオフ周波数以上で複数の
    異なる周波数帯域に分割された複数の高周波成分信号
    と、に分離する周波数成分分離手段と、 前記各高周波成分信号を振幅検波して検波信号を得る振
    幅検波手段と、 前記各高周波成分信号から夫々所定倍の高調波成分信号
    を抽出する高調波成分抽出手段と、 上記各高調波成分信号を前記検波信号により振幅変調し
    利得制御された夫々の振幅変調信号を得る振幅変調手段
    と、 上記各振幅変調信号と前記音響信号の低周波成分信号と
    を合成して合成信号を得る信号合成手段と、 を有することを特徴とする音響信号イコライザ回路。
    1. A frequency component separating means for separating an acoustic signal into a low frequency component signal below a predetermined cutoff frequency and a plurality of high frequency component signals divided into a plurality of different frequency bands above the cutoff frequency. An amplitude detecting means for amplitude-detecting each high-frequency component signal to obtain a detection signal, a harmonic component extracting means for extracting a harmonic component signal of a predetermined multiple from each high-frequency component signal, and each harmonic component Amplitude modulating means for amplitude-modulating a signal by the detection signal to obtain each amplitude-controlled signal whose gain is controlled, and signal synthesis for obtaining a synthesized signal by synthesizing each of the amplitude-modulated signals and the low-frequency component signal of the acoustic signal An acoustic signal equalizer circuit comprising:
  2. 【請求項2】 音響信号を、所定カットオフ周波数以下
    の低周波成分信号と、該カットオフ周波数以上で複数の
    異なる周波数帯域に分割された複数の高周波成分信号
    と、に分離する周波数成分分離手段と、 前記各高周波成分信号を振幅検波して検波信号を得る振
    幅検波手段と、 前記各高周波成分信号のゼロクロス点を検出して各ゼロ
    クロス信号を出力するゼロクロス検出手段と、 上記各ゼロクロス信号を前記検波信号により振幅変調し
    利得制御された夫々の振幅変調信号を得る振幅変調手段
    と、 上記各振幅変調信号と前記各高周波成分信号との各差成
    分信号を抽出する差成分信号出力手段と、 上記各差成分信号と前記音響信号の低周波成分信号とを
    合成して合成信号を得る信号合成手段と、 を有することを特徴とする音響信号イコライザ回路。
    2. A frequency component separating means for separating an acoustic signal into a low frequency component signal below a predetermined cutoff frequency and a plurality of high frequency component signals divided into a plurality of different frequency bands above the cutoff frequency. An amplitude detection means for amplitude-detecting each high-frequency component signal to obtain a detection signal, a zero-cross detection means for detecting a zero-cross point of each high-frequency component signal and outputting each zero-cross signal, and each of the zero-cross signals Amplitude modulation means for obtaining each amplitude modulation signal amplitude-modulated by the detection signal and gain-controlled, difference component signal output means for extracting each difference component signal between each of the amplitude modulation signals and each of the high frequency component signals, and A signal synthesizing means for synthesizing each difference component signal and a low-frequency component signal of the acoustic signal to obtain a synthesized signal. Road.
  3. 【請求項3】 音響信号を、所定カットオフ周波数以下
    の低周波成分信号と、該カットオフ周波数以上で複数の
    異なる周波数帯域に分割された複数の高周波成分信号
    と、に分離する周波数成分分離手段と、 前記各高周波成分信号を振幅検波して検波信号を得る振
    幅検波手段と、 前記各周波成分信号のゼロクロス点を検出して各ゼロク
    ロス信号を出力するゼロクロス検出手段と、 上記各ゼロクロス信号を前記検波信号により振幅変調し
    利得制御された夫々の振幅変調信号を得る振幅変調手段
    と、 上記各振幅変調信号と前記各周波成分信号との各和成分
    信号を抽出する和成分信号出力手段と、 上記各和成分信号と前記音響信号の低周波成分信号とを
    合成して合成信号を得る信号合成手段と、 を有することを特徴とする音響信号イコライザ回路。
    3. A frequency component separating means for separating an acoustic signal into a low frequency component signal below a predetermined cutoff frequency and a plurality of high frequency component signals divided into a plurality of different frequency bands above the cutoff frequency. An amplitude detection means for amplitude-detecting each high-frequency component signal to obtain a detection signal, a zero-cross detection means for detecting a zero-cross point of each frequency component signal and outputting each zero-cross signal, and each of the zero-cross signals Amplitude modulation means for obtaining respective amplitude modulation signals amplitude-modulated by the detection signal and gain-controlled, sum component signal output means for extracting each sum component signal of each of the amplitude modulation signals and each of the frequency component signals, An acoustic signal equalizer circuit comprising: a signal synthesizing unit that synthesizes each sum component signal and a low-frequency component signal of the acoustic signal to obtain a synthesized signal.
  4. 【請求項4】 前記合成信号と前記音響信号とのいずれ
    かを選択して出力する選択出力手段を有することを特徴
    とする請求項1,2又は3に記載の音響信号イコライザ
    回路。
    4. The acoustic signal equalizer circuit according to claim 1, further comprising a selection output unit that selects and outputs one of the synthesized signal and the acoustic signal.
JP4022026A 1992-01-10 1992-01-10 Acoustic signal equalizer circuit Granted JPH05191885A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP4022026A JPH05191885A (en) 1992-01-10 1992-01-10 Acoustic signal equalizer circuit

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP4022026A JPH05191885A (en) 1992-01-10 1992-01-10 Acoustic signal equalizer circuit
US07/993,389 US5388159A (en) 1991-12-20 1992-12-18 Equalizing circuit for reproduced signals

Publications (1)

Publication Number Publication Date
JPH05191885A true JPH05191885A (en) 1993-07-30

Family

ID=12071478

Family Applications (1)

Application Number Title Priority Date Filing Date
JP4022026A Granted JPH05191885A (en) 1992-01-10 1992-01-10 Acoustic signal equalizer circuit

Country Status (1)

Country Link
JP (1) JPH05191885A (en)

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JPH05227588A (en) * 1992-02-12 1993-09-03 Onkyo Corp Acoustic reproducer
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