JPS5911098A - Sound reproducer - Google Patents
Sound reproducerInfo
- Publication number
- JPS5911098A JPS5911098A JP11924582A JP11924582A JPS5911098A JP S5911098 A JPS5911098 A JP S5911098A JP 11924582 A JP11924582 A JP 11924582A JP 11924582 A JP11924582 A JP 11924582A JP S5911098 A JPS5911098 A JP S5911098A
- Authority
- JP
- Japan
- Prior art keywords
- speaker
- amplifier
- output
- signal
- electrode
- 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.)
- Pending
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R3/00—Circuits for transducers, loudspeakers or microphones
- H04R3/002—Damping circuit arrangements for transducers, e.g. motional feedback circuits
Landscapes
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Acoustics & Sound (AREA)
- Signal Processing (AREA)
- Audible-Bandwidth Dynamoelectric Transducers Other Than Pickups (AREA)
- Circuit For Audible Band Transducer (AREA)
Abstract
Description
【発明の詳細な説明】
この発明は、スピーカを含む音響再生系全体の歪を、安
定かつ効果的に低減するようにした音響再生装置に関す
る。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a sound reproduction device that stably and effectively reduces distortion in the entire sound reproduction system including speakers.
従来、スピーカを含む音響再生系全体の歪を改善する音
響再生装置として、例えば第１図に示すようなものが知
られている。この図に示す音響再生装置は、所謂ＭＦＢ
をかけたもので、入力信号ｅ１を増幅器１によシ増幅し
てスピーカ２を駆動する場合、このスピーカ２の出力の
速度成分を検出用ボイスコイル３によって検出し、この
検出信号を帰還制御回路４を介して前記増１８ｉ器１の
入力側に負帰還するようにしたものである。2. Description of the Related Art Conventionally, as a sound reproduction device that improves distortion in the entire sound reproduction system including speakers, for example, the one shown in FIG. 1 is known. The sound reproduction device shown in this figure is a so-called MFB.
When the input signal e1 is amplified by the amplifier 1 to drive the speaker 2, the velocity component of the output of the speaker 2 is detected by the detection voice coil 3, and this detection signal is sent to the feedback control circuit. 4 to the input side of the amplifier 18i.
しかしながら、この第１図に示すような音響再生装置に
おいては、歪成分を含む信号成分を全て負帰還する方式
であるから、犬＃に負帰趙をかけると、位相遅れ等によ
って増幅動作が不安定になる（すなわち発振現象等を生
じ易い）という問題がある。したがって、この種の音響
再生装置は、帰還値を増して歪を低減することは実際に
は極めて困難であシ、このため低域の周波数特性を制御
するような限られた目的のために採用されている゛のが
現状である。However, in the sound reproduction device shown in Fig. 1, all signal components including distortion components are negatively fed back, so if negative feedback is applied to the signal, the amplification operation will be interrupted due to phase lag, etc. There is a problem in that it becomes unstable (that is, it tends to cause oscillation phenomena, etc.). Therefore, it is actually extremely difficult to reduce distortion by increasing the feedback value in this type of sound reproduction device, and for this reason, it is used for limited purposes such as controlling low frequency characteristics. The current situation is that
この発明は、以上の事情ＶＣ鑑み、スピーカを含む音響
再生系全体の歪を、安定かつ効果的に低減することがで
きる音響再生装置を提供するもので、スピーカの出力に
対応する信号成分を検出する検出手段と、前記スピーカ
を駆動する増幅器の入力端の信号に前記検出手段の検出
特性と等価な特性を付与して出力するフィルタ回路とを
各々設けると共に、第１の演算回路によって前記検出手
段の出力とＡｉｌ記フィルタ回路の出力との差を算出し
、第一の演算回路によル入力信号に前記第７の演算回路
の出力を加泗、して前記増幅器の入力端へ供給するよう
にしたものである。In view of the above circumstances, the present invention provides an audio reproduction device that can stably and effectively reduce the distortion of the entire audio reproduction system including the speaker, and detects a signal component corresponding to the output of the speaker. and a filter circuit that imparts characteristics equivalent to the detection characteristics of the detection means to a signal at the input terminal of the amplifier that drives the speaker and outputs the signal, and a first arithmetic circuit that detects the detection means by the first arithmetic circuit. The difference between the output of the Ail filter circuit and the output of the Ail filter circuit is calculated, and the first arithmetic circuit adds the output of the seventh arithmetic circuit to the Ail input signal and supplies the resultant signal to the input terminal of the amplifier. This is what I did.
以下、この発明による音響再生装置の一実施例を図面を
参照しながら詳細に説明する。DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a sound reproducing apparatus according to the present invention will be described in detail below with reference to the drawings.
第一図は、この発明による音響再生装置の一実施例の構
成を示す回路図である。この図において、符号５で示す
ものは加算器（第一の演算回路）であシ、この加請、器
５は、信号入力端子６に入力される入力信号ｅｉと後述
する差動増幅器７（第１の演算回路）の出力とを加榊−
シて増幅器１とフィルタ回路８とへ各々供給するように
なっている。FIG. 1 is a circuit diagram showing the configuration of an embodiment of the sound reproduction device according to the present invention. In this figure, what is indicated by the reference numeral 5 is an adder (first arithmetic circuit). the output of the first arithmetic circuit)
The signal is supplied to the amplifier 1 and the filter circuit 8, respectively.
増幅器１の出力は、スピーカ２のボイスコイル９の一端
に供松され、同ボイスコイル９の他端は接地されている
。次に、このスピーカ２を第３図を参照して詳述すると
、コーン１０に固Ｎされたボビン１１の外周面には、前
記ボイスコイル９以外に円筒状の金属によ環構成された
″ＲＬ極１２ａ（検出手段）が設けられている また、
とのスピーカ２におけるボトムヨーク１３のポールピー
ス１４（ｉｆ！Ｉの面には、円筒状の金属によって構成
された電極１２ｂ（検出手段）が、前記電極１２ａの外
方に、かつ同電極１２ａと同軸的に設けられている。The output of the amplifier 1 is connected to one end of the voice coil 9 of the speaker 2, and the other end of the voice coil 9 is grounded. Next, this speaker 2 will be described in detail with reference to FIG. 3. On the outer peripheral surface of the bobbin 11 fixed to the cone 10, in addition to the voice coil 9, a cylindrical metal ring is formed. An RL pole 12a (detection means) is provided.
On the pole piece 14 (if! installed coaxially.
この場合、電極１２ａの外周面と電極１２ｂの内周面と
の間の間隙は極めて小さく、かつボビン１１が図におけ
る上下方向に振動すると、１Ｌ？、極１２ａと電極１２
ｂとの対向する面の面積が変化するようになってお夛、
これによってコーン１０の変位を電気容量の変化として
検出し得るようになっている。なお、とのスピーカ２Ｆ
！：おいて、１５は環状の磁石、１６は同じく環状のト
ツズヨーク、１７はダンパを各々示している。再び第２
図に戻って、前記電極１２ｂは、直流電源１８によシ接
地電位に対して正電位にバイアスされるようになってい
る。また、電極１２ａは、ボルテージフォロワ１９を構
成する演算増幅器２０の非反転入力端子に接続されると
共に、高抵抗値の抵抗２１を介して接地されている。そ
して、演算増幅器２０の出力は、差動増幅器７の反転入
力端子に供給されている。In this case, the gap between the outer peripheral surface of the electrode 12a and the inner peripheral surface of the electrode 12b is extremely small, and when the bobbin 11 vibrates in the vertical direction in the figure, 1L? , pole 12a and electrode 12
As the area of the surface facing b changes,
This allows the displacement of the cone 10 to be detected as a change in capacitance. In addition, the speaker 2F
! :, 15 is an annular magnet, 16 is also an annular totsu yoke, and 17 is a damper. Second again
Returning to the figure, the electrode 12b is biased to a positive potential with respect to the ground potential by the DC power supply 18. Further, the electrode 12a is connected to a non-inverting input terminal of an operational amplifier 20 constituting the voltage follower 19, and is also grounded via a resistor 21 having a high resistance value. The output of the operational amplifier 20 is supplied to the inverting input terminal of the differential amplifier 7.
一方、フィルタ回路８は、スピーカ２の振幅（変位）−
周波数特性と等価な伝達特性を持つもので、その出力は
差動増幅器７の非反転入力端子に供給されている１）そ
して、この差Ｎｏｒ増幅器７は、フィルタ回路８の出力
からボルテージツメ−ロワ１９の出力を引ａ、シ、この
引Ｊｖ−結果に対応する信号を前記加算器５へ供給する
ようになっている。On the other hand, the filter circuit 8 calculates the amplitude (displacement) of the speaker 2 -
It has a transfer characteristic equivalent to the frequency characteristic, and its output is supplied to the non-inverting input terminal of the differential amplifier 7. The outputs of 19 are subtracted a and ci, and a signal corresponding to the result of subtraction Jv is supplied to the adder 5.
次に、以上の構成におけるこの実施例の作用について説
明する。Next, the operation of this embodiment with the above configuration will be explained.
まず、スピーカ２の振幅−周波数特性は、周知のスピー
カの特性から、第μ図に示すようｖｃ、最低共振周波数
ｆＯを折曲点として周波数の上昇に伴い振幅が略ｌコｄ
Ｂ１０ ＣＴで減衰するような特性となる。一方、第
２図に示す電極１２ｂは正電位にバイアスされ、電極１
２８Ｌは抵抗２１を介して接地されているから、これら
両電極１２ａ。First, the amplitude-frequency characteristics of the speaker 2 are determined from the well-known characteristics of speakers. As shown in Fig. μ, the amplitude decreases as the frequency increases with vc and the bending point at the lowest resonant frequency fO.
The characteristic is such that it is attenuated by B10 CT. On the other hand, the electrode 12b shown in FIG. 2 is biased to a positive potential, and the electrode 12b shown in FIG.
Since 28L is grounded via the resistor 21, both of these electrodes 12a.
１２ｂ間には電荷が蓄積層れることになシ、かつこの電
荷は抵抗２１が高抵抗であるためほとんど流出あるいは
原人しない。した１かって、スピーカ２のコーン１０が
変位して電極１２ａ、１２ｂ間の容量が変化すると、コ
ーン１０の変位ｊａ′（すなわち振幅）に比例し北電圧
が電極１２ａに現われることになる１、以上のことから
、第グ図に示したような振幅−周波特性を持つスピーカ
２の振幅を、ボルテージフォロワの出力端から７１う：
圧信号として取り出すことができる。すなわち、差動増
幅器７の反転入力端子に供給される信号は、スピーカ２
の入出力特性に従ったものとなる。一方、増幅器１の入
力端に供給される信号（すなわちスピーカ２を駆動する
場合の源となる信号）は、フィルタ回路８を介して第μ
図に示した特性と等価な特性が付与δれて差動増幅器７
の非反転入力端子に供給される。したがって差動増幅器
７の出力信号としては、フィルタ回路８の出力からボル
テージフメロン１９の出力を引算した場合の引算結果に
対応する信号すなわち、増幅器１に入力された後スピー
カ２力４ら出力されるまでの間において発生した歪に対
応する信号が得られる。そしてこの差動増幅器７の出力
信−号は７Ｊｉｌ′ＪＡ、器５において人力信号ｊ、ｅ
ｉに前Ｇ己歪を打ち消す方向に加／Ｊ１．される。There is no charge accumulation layer between the resistors 12b and 12b, and since the resistor 21 has a high resistance, this charge hardly leaks out or disappears. Therefore, when the cone 10 of the speaker 2 is displaced and the capacitance between the electrodes 12a and 12b changes, a north voltage will appear at the electrode 12a in proportion to the displacement ja' (that is, the amplitude) of the cone 10. From this, the amplitude of speaker 2, which has the amplitude-frequency characteristics shown in Fig. 7, is calculated from the output end of the voltage follower as follows:
It can be extracted as a pressure signal. That is, the signal supplied to the inverting input terminal of the differential amplifier 7 is
It follows the input/output characteristics of On the other hand, the signal supplied to the input terminal of the amplifier 1 (that is, the signal that becomes the source when driving the speaker 2) is passed through the filter circuit 8 to the μth
The differential amplifier 7 is given characteristics δ equivalent to those shown in the figure.
is supplied to the non-inverting input terminal of Therefore, the output signal of the differential amplifier 7 is a signal corresponding to the subtraction result when the output of the voltage humeron 19 is subtracted from the output of the filter circuit 8. A signal corresponding to the distortion generated before being output is obtained. The output signal of the differential amplifier 7 is 7Jil'JA, and the output signal of the differential amplifier 7 is
Addition to i in the direction of canceling the front G self-distortion/J1. be done.
しかし、この実施例によれば、差動増幅器７およびフィ
ルタ回路８の利得を適当な値に設定することにより、ナ
１９１１〜＋ｉ ’ＩＨ１、増幅器１とスピーカ２との
間の接Ｍｅ ｆ’、ｔｌｉ 、および７ヒ一カ２自体に
おいて発生する歪を完全に打ち消すことができる。そし
てこの場合、加３１−器５に帰還される・［を号は、歪
のみＶこ対応する微小信号であるｋめ、非常に効果的な
かつ極めて女足した帰還をかけることができ、たとえ位
ａ遅れ郷が生じても増幅動作が不安定になるととｅよな
い。：ｔだ、この実施例によれば、スピーカ２の出力の
イー号成分を第Ｖ図に示すような線形な特性を持つ振幅
として取り出すようにしたので、フィルタ回路８を極め
て単純な回路構成とすることかでき、実施上極めて都合
がよい。However, according to this embodiment, by setting the gains of the differential amplifier 7 and the filter circuit 8 to appropriate values, the connections Me f' between the amplifier 1 and the speaker 2, It is possible to completely cancel out the distortion occurring in tli and the 7-hike 2 itself. In this case, the signal fed back to the adder 31-5 is a minute signal corresponding to the distortion only V, so it is possible to apply a very effective and extremely effective feedback. Even if a delay occurs, the amplification operation will become unstable. According to this embodiment, the E component of the output of the speaker 2 is extracted as an amplitude having a linear characteristic as shown in FIG. It is very convenient in terms of implementation.
なお、この実施例においては、スピーカ２の振幅を電極
１２ａ、１２ｂ間の各蓋変化を利用して検出するものと
したが、この振ＩＩＶ、Ｘ変化を、光−抵抗素子等を第
１１用して検出するようにしてもよい。またこの実施例
においては、スピーカ２の出力に対応する信号成分を振
幅として検出したが、スピーカ２の出力に対応する信号
成分を、Ａｉｌ述した検出用ボイスコイル８等を用いて
速度として検出してもよい。ただしこの場合、スピーカ
の速度−周波数％性は、第５図に示すように、最低共振
周波数ｆｏを頂点として周波数が上昇または下降するに
つれて６ｄＢ１０ＣＴで減衰するような特性となるから
、フィルタ回路８の回路構成が複雑化してしまう。In this embodiment, the amplitude of the speaker 2 is detected using the changes in each cover between the electrodes 12a and 12b, but the changes in the amplitude IIV and X are detected by using a photo-resistance element etc. Alternatively, the detection may be performed by Further, in this embodiment, the signal component corresponding to the output of the speaker 2 was detected as the amplitude, but the signal component corresponding to the output of the speaker 2 was detected as the velocity using the detection voice coil 8 described above. It's okay. However, in this case, as shown in FIG. 5, the speed-frequency characteristic of the speaker is such that it attenuates by 6 dB10CT as the frequency rises or falls with the lowest resonant frequency fo at its peak. The circuit configuration becomes complicated.
以上の説明から明らかなように、この発明による音ｖｐ
＋生装置によれば、スピーカの出力に対応する信号成分
を検出する検出手段と、増幅器の入力端の信号にこの検
出手段の検出特性と等価な特性を付与するフィルタ回路
とを設けると共に、第７の演算回路によって前記検出手
段の出力と前記フィルタ回路の出力との差を求め、第２
の演算回路によって入力信号に前記第７の演薯−回路の
出力を加算して前記増幅器の入力端に供給するように構
成したので、増幅器、増１１１ｉ、ｉＲ−とスピーカと
の接続部、およびスピーカ等からなる音響再生系全体の
歪成分を抽出し、この歪成分に対応する微小信号だけを
帰還することによって、極めて高精度にそして効果的に
かつ安定に歪を打ち消すことができる。As is clear from the above explanation, the sound vp according to the present invention
+According to the device, a detection means for detecting a signal component corresponding to the output of the speaker and a filter circuit for imparting characteristics equivalent to the detection characteristics of the detection means to the signal at the input end of the amplifier are provided, and The difference between the output of the detection means and the output of the filter circuit is determined by the arithmetic circuit No. 7, and the second
Since the arithmetic circuit is configured to add the output of the seventh circuit to the input signal and supply it to the input terminal of the amplifier, the amplifier, amplifier 111i, iR- and the connection part between By extracting the distortion components of the entire sound reproduction system including speakers and the like and feeding back only the minute signals corresponding to these distortion components, distortion can be effectively and stably canceled with extremely high precision.
第１図は従来の音響再生装置の一構成例を示す回路図、
第２図はこの発明の一実施例の構成を示す回路図、第３
図は同実施例におけるスピーカ２のｉＰ細な構成を示す
断面図、第Ｖ図はスピーカの振幅−周波数特性図、第５
図はスピーカの速度−周波数特性図である。
１・・・・・・増幅器、２・・・・・・スピーカ、５・
・・・・・第一の演算回路（加算器）、６・・・・・・
信号入力端子、７・・・・・・第７の演算回路（差動増
幅器）、８・・・・・・フィルタ回路、１２ａ、１２ｂ
・・・・・・検出手段（電極）。FIG. 1 is a circuit diagram showing an example of the configuration of a conventional sound reproduction device,
FIG. 2 is a circuit diagram showing the configuration of an embodiment of the present invention, and FIG.
The figure is a sectional view showing the iP detailed configuration of the speaker 2 in the same embodiment, Figure V is an amplitude-frequency characteristic diagram of the speaker, and Figure 5 is a diagram showing the amplitude-frequency characteristics of the speaker.
The figure is a speed-frequency characteristic diagram of a speaker. 1...Amplifier, 2...Speaker, 5.
...First arithmetic circuit (adder), 6...
Signal input terminal, 7...7th arithmetic circuit (differential amplifier), 8...filter circuit, 12a, 12b
...Detection means (electrode).
Claims (1)
ーカの出力に対応する信号成分を検出する検出手段と、
前記増幅器の入力端の信号を入力しこの信号を１１５記
検出手段の検出特性に対応する特性にしたがって出力す
るフィルタ回路と、０１Ｊ記検出手段の出力と前記フィ
ルタ回路の出力との差を寝−１出する第７の演算回路と
、入力信号に前記第１の演算回路の出力を加算して前記
増幅器の入力端に供給する第２の演算回路とを具備して
なることを特徴とする音響再生装置。an amplifier for driving a speaker; a detection means for detecting a signal component corresponding to the output of the speaker from the speaker;
a filter circuit which inputs the signal at the input terminal of the amplifier and outputs this signal according to a characteristic corresponding to the detection characteristic of the detection means described in No. 115; 1, and a second arithmetic circuit that adds the output of the first arithmetic circuit to an input signal and supplies the result to the input end of the amplifier. playback device.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP11924582A JPS5911098A (en) | 1982-07-09 | 1982-07-09 | Sound reproducer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP11924582A JPS5911098A (en) | 1982-07-09 | 1982-07-09 | Sound reproducer |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS5911098A true JPS5911098A (en) | 1984-01-20 |
Family
ID=14756551
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP11924582A Pending JPS5911098A (en) | 1982-07-09 | 1982-07-09 | Sound reproducer |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5911098A (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4555797A (en) * | 1983-09-15 | 1985-11-26 | U.S. Philips Corporation | Hybrid loudspeaker system for converting digital signals to acoustic signals |
| US5382463A (en) * | 1991-06-11 | 1995-01-17 | Imperial Chemical Industries Plc | Data storage media |
| JP2007020152A (en) * | 2005-06-07 | 2007-01-25 | Nidec Pigeon Corp | Speaker |
| US7209796B2 (en) | 2001-04-30 | 2007-04-24 | The United States Of America As Represented By The Secretary Of The Department Of Health And Human Services, Centers For Disease Control And Prevention | Auscultatory training system |
| JP2008113108A (en) * | 2006-10-30 | 2008-05-15 | Teac Corp | Speaker |
| CN113495589A (en) * | 2021-06-02 | 2021-10-12 | 上海交通大学 | Supercritical shafting vibration damper based on nonlinear analog circuit |
-
1982
- 1982-07-09 JP JP11924582A patent/JPS5911098A/en active Pending
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4555797A (en) * | 1983-09-15 | 1985-11-26 | U.S. Philips Corporation | Hybrid loudspeaker system for converting digital signals to acoustic signals |
| US5382463A (en) * | 1991-06-11 | 1995-01-17 | Imperial Chemical Industries Plc | Data storage media |
| US7209796B2 (en) | 2001-04-30 | 2007-04-24 | The United States Of America As Represented By The Secretary Of The Department Of Health And Human Services, Centers For Disease Control And Prevention | Auscultatory training system |
| JP2007020152A (en) * | 2005-06-07 | 2007-01-25 | Nidec Pigeon Corp | Speaker |
| JP2008113108A (en) * | 2006-10-30 | 2008-05-15 | Teac Corp | Speaker |
| JP4760668B2 (en) * | 2006-10-30 | 2011-08-31 | ティアック株式会社 | Speaker |
| CN113495589A (en) * | 2021-06-02 | 2021-10-12 | 上海交通大学 | Supercritical shafting vibration damper based on nonlinear analog circuit |
| CN113495589B (en) * | 2021-06-02 | 2022-02-18 | 上海交通大学 | Supercritical shafting vibration damper based on nonlinear analog circuit |
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