JPS5948817A - Equalizer circuit - Google Patents

Equalizer circuit

Info

Publication number
JPS5948817A
JPS5948817A JP15846982A JP15846982A JPS5948817A JP S5948817 A JPS5948817 A JP S5948817A JP 15846982 A JP15846982 A JP 15846982A JP 15846982 A JP15846982 A JP 15846982A JP S5948817 A JPS5948817 A JP S5948817A
Authority
JP
Japan
Prior art keywords
equalizer
amplifier
output
negative feedback
circuit
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
JP15846982A
Other languages
Japanese (ja)
Other versions
JPH0349122B2 (en
Inventor
Mamoru Sekiya
守 関谷
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shin Shirasuna Electric Corp
Original Assignee
Shin Shirasuna Electric Corp
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 Shin Shirasuna Electric Corp filed Critical Shin Shirasuna Electric Corp
Priority to JP15846982A priority Critical patent/JPS5948817A/en
Publication of JPS5948817A publication Critical patent/JPS5948817A/en
Publication of JPH0349122B2 publication Critical patent/JPH0349122B2/ja
Granted legal-status Critical Current

Links

Classifications

    • GPHYSICS
    • G11INFORMATION STORAGE
    • G11BINFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/02Recording, reproducing, or erasing methods; Read, write or erase circuits therefor
    • G11B5/027Analogue recording
    • G11B5/035Equalising

Abstract

PURPOSE:To perform equalization free from distortion, by providing a feedback circuit in which equalizer elements equivalent to each other in terms of impedance are connected in series with a buffer amplifier connected via the equa- lizer element at the output side of a constant current driving amplfier. CONSTITUTION:The input signal sent from a record player, etc. is fed to a constant current driving amplifier 6, and the output of the amplfier 6 is supplied to an equalizer element 7. The equalized output subjected to receive the high band attenuating function by the element 7 is converted into a low impedance by a buffer amplifier 8. While a part of the output of the amplifier 8 is fed back to the negative input side of the amplifier 6 by a negative feedback circuit 10 via an equalizer element 9. The elements 7 and 9 are set equal to each other in terms of impedance. This eliminates the transient cross modulation distortion caused by the application of excessive negative feedback. Thus the satisfactory equalization is ensured with reduced distortion.

Description

【発明の詳細な説明】 この発明は、テープレコーダ、レコードプレーヤー等の
信号再生囲路において使用されるイコライザ回路に関し
、特に、2つのイコライザ回路をオープンループとクロ
ーズトループ回路に使用して、オープンループ特性とク
ローズトル−プ特性を組合せ、周波数に対しほぼ一定な
負・層還量を選択できるようにすることにょシ、負帰還
に起因したj1υ1的歪(過渡混変調歪)の発生を防止
する。]:うにしたイコライザ回路に関する。
DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an equalizer circuit used in a signal reproduction circuit of a tape recorder, a record player, etc., and in particular, two equalizer circuits are used for an open loop circuit and a closed loop circuit, and an open loop circuit is used. By combining the characteristics and the closed-loop characteristics, it is possible to select a negative/layer feedback amount that is almost constant with respect to the frequency, and to prevent the occurrence of j1υ1 distortion (transient intermodulation distortion) caused by negative feedback. . ]: Concerning the equalizer circuit.

従来、レコードプレーヤ等の信号再生に使用されていた
イコライザ回路は、例えば、第1図のように、RIAA
規格のRI A、 Aカーブを得るイコライザ素子1を
直列に挿入した負帰還回路を増幅器2.乙の回路に接続
したNF型イコライザ回路がある。
Conventionally, equalizer circuits used for signal reproduction in record players and the like are, for example, RIAA equalizer circuits as shown in Figure 1.
A negative feedback circuit in which equalizer element 1 is inserted in series to obtain standard RI A and A curves is connected to amplifier 2. There is an NF type equalizer circuit connected to the circuit of Part B.

しかし、この種の負帰還型のイコライザl!″il路で
は、第2図に示すように、増幅器2.6の裸ゲイン特性
が高域になるほど一様に減衰するAのような特性である
場合、負帰還をかけること、に工って13のように中域
あたりから減衰する周波数特性をつくるように動作する
However, this type of negative feedback equalizer l! In the il path, as shown in Figure 2, if the bare gain characteristic of the amplifier 2.6 is a characteristic like A, which attenuates uniformly as the frequency increases, applying negative feedback is a good idea. 13, it operates to create a frequency characteristic that attenuates from around the midrange.

したがって、第2図の出力レベ/I/A線とJ3iji
+にの差が負帰還量となるが、この負帰還量が中域から
高域にかけて大きくなり、大量の負帰還をかけることに
よって、増幅器内の信号と負帰還信号の位4゛目差から
、信号の他にそのJ:ll又は差の成分が発生して混変
調が起り、過渡混変調歪を増大さぜる問題があった。
Therefore, the output level /I/A line in Fig. 2 and J3iji
The difference between , a J:ll or difference component is generated in addition to the signal, resulting in cross-modulation, which poses a problem of increasing transient cross-modulation distortion.

一方、他のイコライザ回路として、第3図に示すよりに
、増幅器4の出力側にC几型のイコライザ素子5を接i
読するc LL型イコライザ回路がある。しかし、この
イコライザ回路では負帰還をがけないためにこれGこ起
因した過渡混変調歪は生じないか、大きい出力信号を取
出ずことができない欠点があつ7辷っ この・箔f9イは、」二記の点にM目し、負帰歯をかけ
ることにより信号増幅時の歪を減少させると共に、その
負帰還1辻を任意に選択できるようにして有効な周波数
帯域Gこおいて均等な負帰)’HM tがけることがで
き、過度の〔1帰還をかけることに、・1因しだ渦イ度
l昆変調歪の発生を防止することができるイコライザ凹
]洛の提供を目的とする。このために、本発明は、定電
流駆動型の増幅器の出力側に第1イコライザ素子を介し
てバッファアンプをJ妾続し、該バッフ7アノプの出力
側と増1陥品の負入力側との間に、第2−(コライザ素
子を直列に接続した負帰還回路を接続し、且つ第1イコ
フイザ素子を第2イコライザ素子とインピーダンス的に
等価にしだことを要旨としている。
On the other hand, as another equalizer circuit, as shown in FIG. 3, a C type equalizer element 5 is connected to the output side of the amplifier 4.
Read c There is an LL type equalizer circuit. However, since this equalizer circuit does not provide negative feedback, there is no transient cross-modulation distortion caused by this, or a large output signal cannot be extracted. By applying a negative feedback gear to the second point M, distortion during signal amplification can be reduced, and by making it possible to arbitrarily select one point of the negative feedback, an equal negative feedback can be achieved over the effective frequency band G. The purpose is to provide an equalizer that can apply HMt and prevent the occurrence of excessive vorticity and modulation distortion due to the application of one feedback. do. For this purpose, the present invention connects a buffer amplifier to the output side of a constant current drive type amplifier via a first equalizer element, and connects the output side of the buffer amplifier and the negative input side of the amplifier. In between, a negative feedback circuit having a second equalizer element connected in series is connected, and the first equalizer element is made equivalent to the second equalizer element in terms of impedance.

以下、この発明の実施例を121而(こ(、(づいごj
j’L明する。
Hereinafter, 121 embodiments of this invention will be described.
j'L light up.

i 4 図i、ルコードプレーヤに関する几I A A
 規格に準シたイコライザ回路のブロック図を示し、6
は定電流駆動型の増幅Agであり、この増111.・1
i ;+146の出力側にはCR型の第1イコライザ素
千7が接続される。さらに、イコライザ回路7の出力(
111日こはバッファアップ8が出力インピーダンスの
変1%用として接続される。そして、バッファアップ8
の出力側と増幅器6の負入力側にN F :21’fj
のi:l’s 2・rコライザ素子9を直列接、読した
で1帰還回路10が接続される。ここで、第1イコブイ
ザ素子7は第2イコライザ累子9とインピーダンス的に
ほり丁4;l’、z価に構成されている。
i 4 Figure i, 几I A A regarding the code player
A block diagram of an equalizer circuit conforming to the standard is shown, and 6
is a constant current drive type amplification Ag, and this amplification 111.・1
A CR type first equalizer element 7 is connected to the output side of i;+146. Furthermore, the output of the equalizer circuit 7 (
On the 111th day, a buffer up 8 is connected for changing the output impedance by 1%. And buffer up 8
N F :21'fj on the output side of the amplifier 6 and the negative input side of the amplifier 6.
The i:l's 2.r equalizer element 9 is connected in series, and the 1 feedback circuit 10 is connected. Here, the first equalizer element 7 and the second equalizer resistor 9 are configured to have an impedance ratio of 4; l' and a z value.

このように]イ4成されたイコライザ回路では、増幅器
乙に入力された入力信号は、増1lll′I′l益6が
定市;流ドライブのアンプであるCとから、すrz/イ
コライザ素子7の負荷インピーダンスに対応した出力電
圧が得られる。そして、この出力r/′i第/イコライ
ザ素子7を通されることにより、この素子のもつ高域減
衰作用を受けて、第3図のRI A、 AカーブCに示
す出力信号が得られる。これによシ等化出力が第1イコ
ライザ素子7から出力され、さらに、バッファアンプ8
により高いインピーダンスは低インピーダンスに変換さ
れる。
In the equalizer circuit constructed in this manner, the input signal input to the amplifier B is increased by 1llll'I'l gain 6 from C, which is a current drive amplifier, to the equalizer element C. An output voltage corresponding to a load impedance of 7 is obtained. Then, by passing this output through the r/'ith/equalizer element 7, the high frequency attenuation effect of this element is applied, and an output signal shown in RI A, A curve C in FIG. 3 is obtained. As a result, an equalized output is output from the first equalizer element 7, and further, the buffer amplifier 8
The higher impedance is converted to lower impedance.

一方、バッファアップ8の出力の一部は負帰還(tIl
路’lOB、:、r、つて増幅器6の負入力側にフィー
ドバックされ、この回路に挿入されたNF型の第2イコ
ライザ素子9により、第3−図に示す負帰革だけ負帰還
がかけられる。負帰還回路10の第Ωイコライザ素子9
と増幅器乙の出力側に接続された第1イコライザ素子7
とほぼ同一の時定数をもつことから、第1イコライザ素
子7によって等化した周波数に対する1」3カレベルの
減衰性と同様な特性をもつ工9に動作し、第1イコライ
ザ素子7によるオープンループ特性と第Ωイコライザ素
子9によるクローズトル−プ特性をAil’iみ合せる
ことにより、第S(図Gこ示すRI A AカーゾDの
よりlこ、IL I A AカーブCと同一の1頃きの
周波数特性をもつ出力をイコライザ回路から出力させる
ことができる。脣た、この周波数の変化にオLしてはト
ゲ一定した負帰還量は第1イコフイザ素子7と第2イコ
ライザ素子9のもつ時定数によって任意に決めることが
できるから、回路構成−ヒ、充分月つ適正な負帰還をか
けて動作させることができる。したがって、過度の負帰
還をかけることに起因した過71に混変調歪をなくし、
歪の少ない良始なイコライゼイションを行なうことがで
きる。
On the other hand, a part of the output of buffer up 8 has negative feedback (tIl
The circuit 'lOB, :, r is fed back to the negative input side of the amplifier 6, and the NF type second equalizer element 9 inserted in this circuit applies negative feedback by the negative feedback shown in Fig. 3. . Ω-th equalizer element 9 of negative feedback circuit 10
and the first equalizer element 7 connected to the output side of amplifier B
Since it has almost the same time constant as the first equalizer element 7, it operates as a device 9 with characteristics similar to the 1"3 level attenuation for the frequency equalized by the first equalizer element 7, and the open loop characteristic by the first equalizer element 7. By combining the closed-loop characteristics of the Ω-th equalizer element 9 and the closed-torp characteristic of the Ω-th equalizer element 9, the S-th (FIG. The equalizer circuit can output an output having a frequency characteristic of Since the constant can be arbitrarily determined, the circuit configuration can be operated with sufficient negative feedback.Therefore, cross-modulation distortion caused by applying excessive negative feedback can be avoided. lost,
It is possible to perform good initial equalization with little distortion.

なお、上記の実施例では、イコライザ素子として、レコ
ードプレーヤに門するIt I A A規格に基づく回
路を使用したが、テープレコーダにIIIするN A、
 B規格、その他D I N 、 J I S規格等の
再生周波数補償の規格に基づくイコライザ素子を使用す
ることができる。
In the above embodiment, a circuit based on the IT IAA standard for record players was used as the equalizer element;
An equalizer element based on reproduction frequency compensation standards such as B standard, DIN, JIS standard, etc. can be used.

以」二説明したようしこ、この発明のイコライザ1[)
1路によれば、定電流駆動型の増幅器の出力側に第1イ
コライザ素子を介してバツファアンブヲi Kcし、こ
のバッファアンプの出力Gil+と増幅:)片の負入力
端間に、第2イコライザ素子を直列に接続した負帰還回
路を接続し、第1イコライザ素子を第2イコライザ素子
とインピーダンス的に等価にして構成したから、周波数
に対しでほぼ一定な負帰還量を任意に選択することがで
き、回路構成上充分す負帰還をかけて壬のないイコライ
ゼイション動作を行なうことができる。まだ、周波数の
変化に苅して均等々負帰還はが得られるから、従来の工
9に一部の周波数領域しこおいて過度の負帰還量による
過渡混変調歪を発生させず、良好な等化性能を確保でき
る等の効果を奏する。
As explained above, the equalizer 1 of this invention [)
According to the first path, a buffer amplifier is connected to the output side of a constant current drive type amplifier via a first equalizer element, and a second equalizer element is connected between the output Gil+ of this buffer amplifier and the negative input terminal of the amplified half. Since a negative feedback circuit is connected in series, and the first equalizer element is made equal to the second equalizer element in terms of impedance, it is possible to arbitrarily select the amount of negative feedback that is approximately constant with respect to frequency. Therefore, it is possible to perform a perfect equalization operation by applying sufficient negative feedback due to the circuit configuration. However, since negative feedback can be obtained evenly depending on the frequency change, it is possible to apply a partial frequency range to the conventional method 9 without causing transient cross-modulation distortion due to excessive negative feedback, and to obtain a good result. This provides effects such as ensuring equalization performance.

【図面の簡単な説明】[Brief explanation of drawings]

第1図と第3図は従来のイコライザ(回路のブロック図
、第2図は第1図の回路の出力の周波数特性を示すグラ
フ、第7図は本発明の実7強例を示すイコライザ回路の
ブロック図、第S図は同回路の出力の周波数特性を示す
グラフである。 6・・・増幅器、7・・・第1イコライザ累子、8・・
・バッファアンプ、9・・・第2イコライザJ(−1+
0・・・負帰還回路。 第 1 図 第 2 図 第 3 図
Figures 1 and 3 are block diagrams of conventional equalizer circuits, Figure 2 is a graph showing the frequency characteristics of the output of the circuit in Figure 1, and Figure 7 is an equalizer circuit showing seven examples of the present invention. Figure S is a graph showing the frequency characteristics of the output of the circuit. 6... Amplifier, 7... First equalizer converter, 8...
・Buffer amplifier, 9...2nd equalizer J (-1+
0...Negative feedback circuit. Figure 1 Figure 2 Figure 3

Claims (1)

【特許請求の範囲】[Claims] 定電流駆動型の増幅器の出力側に第1イコライザ素子を
介してバッファアンプを接続し、該バッファアンプの出
力側と前記増幅器の負入力側との間に、第3イコライザ
素子を直列に接続した負帰還回路を接続し、且つ前記第
1イコライザ素子を第2イコライザ素子とインピーダン
ス的に等価にしたことを特徴とするイコライザ回路。
A buffer amplifier was connected to the output side of the constant current drive type amplifier via a first equalizer element, and a third equalizer element was connected in series between the output side of the buffer amplifier and the negative input side of the amplifier. An equalizer circuit, characterized in that a negative feedback circuit is connected, and the first equalizer element is made equivalent to the second equalizer element in terms of impedance.
JP15846982A 1982-09-11 1982-09-11 Equalizer circuit Granted JPS5948817A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP15846982A JPS5948817A (en) 1982-09-11 1982-09-11 Equalizer circuit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP15846982A JPS5948817A (en) 1982-09-11 1982-09-11 Equalizer circuit

Publications (2)

Publication Number Publication Date
JPS5948817A true JPS5948817A (en) 1984-03-21
JPH0349122B2 JPH0349122B2 (en) 1991-07-26

Family

ID=15672419

Family Applications (1)

Application Number Title Priority Date Filing Date
JP15846982A Granted JPS5948817A (en) 1982-09-11 1982-09-11 Equalizer circuit

Country Status (1)

Country Link
JP (1) JPS5948817A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0718853U (en) * 1994-08-01 1995-04-04 アルプス電気株式会社 Ribbon cassette

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0718853U (en) * 1994-08-01 1995-04-04 アルプス電気株式会社 Ribbon cassette

Also Published As

Publication number Publication date
JPH0349122B2 (en) 1991-07-26

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