JPH0255500A - Piezoelectric speaker equipment - Google Patents
Piezoelectric speaker equipmentInfo
- Publication number
- JPH0255500A JPH0255500A JP20665788A JP20665788A JPH0255500A JP H0255500 A JPH0255500 A JP H0255500A JP 20665788 A JP20665788 A JP 20665788A JP 20665788 A JP20665788 A JP 20665788A JP H0255500 A JPH0255500 A JP H0255500A
- Authority
- JP
- Japan
- Prior art keywords
- low
- volume
- piezoelectric speaker
- frequency
- sound volume
- 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
- 230000005236 sound signal Effects 0.000 claims abstract description 15
- 230000002238 attenuated effect Effects 0.000 claims abstract description 4
- 239000003990 capacitor Substances 0.000 abstract description 8
- 238000010586 diagram Methods 0.000 description 4
- 210000005069 ears Anatomy 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 238000004904 shortening Methods 0.000 description 1
Abstract
Description
【発明の詳細な説明】
（産業上の利用分野）
本発明は、圧電スピーカをオーディオ周波数再生モニタ
ーとして使用する圧電スピーカ装置に関するものである
。DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a piezoelectric speaker device that uses a piezoelectric speaker as an audio frequency reproduction monitor.
（従来の技術）
圧電スピーカ装置は、従来、時計や電卓などの各種機器
において広く使用されており、通常第５図（、）に示す
ように、圧電スピーカ１．低周波電力増幅器２．音量調
節器３およびオーディオ信号入力端子４等から構成され
ている。(Prior Art) Piezoelectric speaker devices have conventionally been widely used in various devices such as watches and calculators, and generally, as shown in FIG. Low frequency power amplifier 2. It is comprised of a volume controller 3, an audio signal input terminal 4, and the like.
（発明が解決しようとする課題）
ところが、圧電スピーカに使用されている圧電素子は弾
性係数が小さく、しかも内部損失が非常に小さいため、
振動させると、第５図（ｂ）に示すように特定の周波数
で鋭い共振が発生し、オーディオ信号の歪が大きくなる
と、特に高周波成分が耳につき、音楽、アナウンス等の
モニター用として−様な再生を要求されるスピーカ装置
として好ましくない。つまり、圧電スピーカ１を平坦な
周波数特性をもつ低周波電力増幅器２の負荷として接続
した場合、音量調節器３の調節によって低周波電力増幅
器２に入力するオーディオ信号のレベルが大きくなるに
つれ、低周波電力増幅器２の出力歪が増加し、その結果
、圧電スピーカ１に歪んだオーディオ信号が入力される
と、中低域の歪成分である高調波が特に強調して再生さ
れ、また、本来耳につきやすい高域は、基本波、高調波
がともに強調されるため、非常に聞きずらい音質になっ
てしまう。(Problem to be solved by the invention) However, since the piezoelectric elements used in piezoelectric speakers have a small elastic modulus and an extremely small internal loss,
When vibrated, a sharp resonance occurs at a specific frequency as shown in Figure 5(b), and when the distortion of the audio signal becomes large, the high frequency components in particular reach the ears, making it useful for monitoring music, announcements, etc. This is not desirable as a speaker device that requires reproduction. In other words, when the piezoelectric speaker 1 is connected as a load to the low frequency power amplifier 2 with flat frequency characteristics, as the level of the audio signal input to the low frequency power amplifier 2 increases by adjusting the volume controller 3, the low frequency The output distortion of the power amplifier 2 increases, and as a result, when a distorted audio signal is input to the piezoelectric speaker 1, the harmonics, which are distortion components in the mid-low range, are particularly emphasized and reproduced, and the harmonics that are originally unpleasant to the ear are reproduced. In the high frequency range, both the fundamental wave and harmonics are emphasized, resulting in a sound quality that is extremely difficult to hear.
圧電スピーカとしても、従来からその構造、材質等の様
々な改良がなされているが、構造が複雑になり過ぎる等
の問題があり、効果的な方法は見出されていない。Various improvements have been made to the structure, materials, etc. of piezoelectric speakers, but there are problems such as the structure becoming too complex, and no effective method has been found.
また、歪の少ない低周波電力増幅器を実現するためには
、高い電源電圧を必要とするため、小型のポータプル機
器ではＤＣ−ＤＣコンバータ等により電源電圧を昇圧し
なければならない。そのために消費電流が極端に増加し
、機器の電池寿命が短くなってしまう等、実用性に欠け
る。Furthermore, in order to realize a low-frequency power amplifier with low distortion, a high power supply voltage is required, so in small portable devices, the power supply voltage must be boosted by a DC-DC converter or the like. This results in an extremely high current consumption, shortening the battery life of the device, and thus lacking in practicality.
（課題を解決するための手段）
上記問題点を解決するために、本発明の圧電スピーカ装
置は、オーディオ信号入力端子と、このオーディオ信号
レベルを調整する音量調節器と、この音量調節器による
音量調節レベルが小さい時は帯域の広い周波数特性をも
ち、音量調節レベルが大きくなるにつれ、低域および高
域が減衰される周波数特性が得られるように定数設定さ
れた前記音量調節器に連動するイコライザ回路と、前記
音量調節器および前記イコライザ回路によって調節され
たオーディオ信号を増幅する低周波電力増幅器と、この
低周波電力増幅器に負荷として接続される圧電スピーカ
とで構成している。(Means for Solving the Problems) In order to solve the above-mentioned problems, a piezoelectric speaker device of the present invention includes an audio signal input terminal, a volume controller for adjusting the level of the audio signal, and a volume controller using the volume controller. an equalizer that is linked to the volume controller and has a constant set so as to have a frequency characteristic with a wide band when the adjustment level is small, and a frequency characteristic in which low and high frequencies are attenuated as the volume adjustment level increases; A low frequency power amplifier that amplifies the audio signal adjusted by the volume controller and the equalizer circuit, and a piezoelectric speaker connected as a load to the low frequency power amplifier.
（作 用）
本発明は上記した構成によって、音量が小さく歪の少な
いオーディオ信号を再生する場合には、帯域の広い周波
数音圧特性で忠実度の高い再生を行ない、音量が大きく
歪の多いオーディオ信号を再生する場合には、低域およ
び高域を減衰した周波数音圧特性で耳につきやすい高調
波成分を減衰させることにより、音楽やアナウンス等を
再生するのに適した周波数音圧特性を得ることができる
。(Function) With the above-described configuration, the present invention performs high-fidelity reproduction with a wide frequency sound pressure characteristic when reproducing audio signals with low volume and low distortion, and reproduces audio signals with high volume and high distortion. When reproducing signals, frequency sound pressure characteristics suitable for reproducing music, announcements, etc. are obtained by attenuating harmonic components that are easy to hear with frequency sound pressure characteristics that attenuate low and high frequencies. be able to.
（実施例）
以下、本発明の一実施例の圧電スピーカ装置について、
図面を参照しながら説明する。(Example) Hereinafter, a piezoelectric speaker device according to an example of the present invention will be described.
This will be explained with reference to the drawings.
第１図に本発明の一実施例における圧電スピーカ装置の
構成を示す。FIG. 1 shows the configuration of a piezoelectric speaker device according to an embodiment of the present invention.
第１図において、１は第５図（ｂ）の周波数音圧特性を
もつ圧電スピーカ、２は平坦な周波数特性をもつ低周波
電力増幅器、３は音量調節器である５０にΩ（ＪＩＳＢ
カーブ）の可変抵抗器、４はオーディオ信号入力端子で
ある。また、５，６，７゜８．９，１．０はそれぞれｃ
１＝ｏ、ｏｉμＦ、 Ｃ２＝０．０１μＦ。In Fig. 1, 1 is a piezoelectric speaker with the frequency sound pressure characteristics shown in Fig. 5(b), 2 is a low-frequency power amplifier with flat frequency characteristics, and 3 is a volume adjuster.
4 is an audio signal input terminal. Also, 5, 6, 7° 8.9, 1.0 are c
1=o, oiμF, C2=0.01μF.
Ｃ，＝０．００２２μＦ、 Ｃ４＝０．０１μＦ、 Ｃ
３＝０．０２２μＦ、 Ｃ。C,=0.0022μF, C4=0.01μF, C
3=0.022μF, C.
＝０．０１μＦのコンデンサであり、１１．１２はそれ
ぞれＲ１＝２２にΩ、Ｒ２＝２２にΩの抵抗である。=0.01 μF capacitor, and 11.12 are resistors of Ω for R1=22 and Ω for R2=22, respectively.
可変抵抗器３とコンデンサ５〜ＩＯおよび抵抗１１゜１
２によって音量調節器３に連動するイコライザ回路を形
成しており、コンデンサ７．８によって高域の周波数特
性が、また、コンデンサ５，６，９゜１０および抵抗１
１．１２によって低域の周波数特性が決定される。Variable resistor 3 and capacitor 5 to IO and resistor 11゜1
2 forms an equalizer circuit that is linked to the volume adjuster 3, and capacitors 7 and 8 control high frequency characteristics, and capacitors 5, 6, 9° 10 and resistor 1
1.12 determines the low frequency characteristics.
可変抵抗器３によって分割された抵抗を１３（Ｒ３）、
１４（Ｒ４）として、前記イコライザ回路の等＝４
価回路を第２図に示す。但し、Ｒ３＋Ｒ４＝５０にΩ、
１５の信号源インピーダンスをＲ５＝１０にΩとし、１
６の低周波電力増幅器の入力インピーダンスをＲ，＝５
０にΩとした。The resistance divided by the variable resistor 3 is 13 (R3),
14 (R4), an equal = 4 circuit of the equalizer circuit is shown in FIG. However, R3+R4=50Ω,
The signal source impedance of 15 is set to Ω with R5=10, and 1
The input impedance of the low frequency power amplifier of 6 is R, = 5
Ω was set to 0.
音量が小さい時はＲ３＝４５にΩ、Ｒ，＝５にΩ、音量
中程度の時はＲ，＝Ｒ４＝２５にΩ、音量が大きい時は
Ｒ，＝５にΩ、 Ｒ，＝４５にΩとして、各周波数にお
けるイコライザ回路での減衰量を計算した結果を第３図
に示す。第３図において、曲線■は音量小、曲線■は音
量中程度、曲線■は音量大の時の周波数特性を示す。When the volume is low, R3 = 45 Ω, R, = 5 Ω, when the volume is medium, R4 = 25 Ω, when the volume is high, R, = 5 Ω, R, = 45. FIG. 3 shows the results of calculating the amount of attenuation in the equalizer circuit at each frequency, where Ω is used. In FIG. 3, the curve ■ shows the frequency characteristics when the volume is low, the curve ■ shows the frequency characteristics when the volume is medium, and the curve ■ shows the frequency characteristics when the volume is high.
低周波電力増幅器２の入力側にこのイコライザ回路を挿
入することにより、本実施例の圧電スピーカ装置の周波
数音圧特性は第４図のようになり、曲線■→■→■と音
量が大きくなるにつれて低域および高域を減衰させ、圧
電スピーカの再生音を音楽やアナウンス等に適したもの
にすることができる。By inserting this equalizer circuit into the input side of the low frequency power amplifier 2, the frequency sound pressure characteristics of the piezoelectric speaker device of this embodiment become as shown in Fig. 4, and the volume increases as the curve ■→■→■ As a result, the low and high frequencies are attenuated, making it possible to make the sound reproduced by the piezoelectric speaker suitable for music, announcements, and the like.
（発明の効果）
以上の説明で明らかなように、本発明による圧電スピー
カ装置によれば、音量が大きく歪の多いオーディオ信号
を再生する場合でも、音楽やアナウンス等を再生するの
に適した周波数特性を得ることができる。(Effects of the Invention) As is clear from the above explanation, the piezoelectric speaker device according to the present invention can maintain a frequency suitable for reproducing music, announcements, etc. even when reproducing an audio signal with a large volume and a lot of distortion. characteristics can be obtained.
第１図は本発明の一実施例における圧電スピーカ装置の
構成を示す図、第２図は本発明の一実施例における圧電
スピーカ装置を構成する音量調節器に連動するイコライ
ザ回路の等何回路を示す図、第３図は第２図に示したイ
コライザ回路の周波数特性を示す図、第４図は本発明の
一実施例における圧電スピーカ装置の周波数音圧特性を
示す図、第５図（ａ）、（ｂ）は従来の圧電スピーカ装
置の構成とその周波数音圧特性を示す図である。
１・・・圧電スピーカ、 ２・・・低周波電力増幅器、
３・・音量調節器、 ４・・オーディオ入力端子、
５，６，７，８，９，１．０・・・コンデンサ、 １１
．１２．１３．１４・・・抵抗、 １５・・・オーディ
オ入力信号源インピーダンス、１６・・低周波電力増幅
器２の入力インピーダンス。FIG. 1 is a diagram showing the configuration of a piezoelectric speaker device according to an embodiment of the present invention, and FIG. 2 is a diagram showing the configuration of an equalizer circuit linked to a volume adjuster constituting the piezoelectric speaker device according to an embodiment of the present invention. FIG. 3 is a diagram showing the frequency characteristics of the equalizer circuit shown in FIG. ) and (b) are diagrams showing the configuration of a conventional piezoelectric speaker device and its frequency sound pressure characteristics. 1... Piezoelectric speaker, 2... Low frequency power amplifier,
3.Volume adjuster, 4.Audio input terminal,
5, 6, 7, 8, 9, 1.0... capacitor, 11
．． 12.13.14...Resistance, 15...Audio input signal source impedance, 16...Input impedance of low frequency power amplifier 2.
Claims (1)
を調節する音量調節器と、この音量調節器による音量調
節レベルが小さい時は帯域の広い周波数特性をもち、音
量調節レベルが大きくなるにつれ、低域および高域が減
衰される周波数特性が得られるように定数設定された前
記音量調節器に連動するイコライザ回路と、前記音量調
節器および前記イコライザ回路によって調節されたオー
ディオ信号を増幅する低周波電力増幅器と、この低周波
電力増幅器に負荷として接続される圧電スピーカを備え
たことを特徴とする圧電スピーカ装置。An audio signal input terminal, a volume controller that adjusts the audio signal level, and a volume controller that has a wide frequency response when the volume adjustment level is low, and as the volume adjustment level increases, the low and high frequencies an equalizer circuit interlocked with the volume adjuster whose constant is set so as to obtain a frequency characteristic in which the frequency range is attenuated; and a low-frequency power amplifier that amplifies the audio signal adjusted by the volume adjuster and the equalizer circuit. A piezoelectric speaker device comprising a piezoelectric speaker connected as a load to this low frequency power amplifier.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP20665788A JPH0255500A (en) | 1988-08-20 | 1988-08-20 | Piezoelectric speaker equipment |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP20665788A JPH0255500A (en) | 1988-08-20 | 1988-08-20 | Piezoelectric speaker equipment |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0255500A true JPH0255500A (en) | 1990-02-23 |
Family
ID=16526981
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP20665788A Pending JPH0255500A (en) | 1988-08-20 | 1988-08-20 | Piezoelectric speaker equipment |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0255500A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2001028799A (en) * | 1999-05-10 | 2001-01-30 | Sony Corp | Onboard sound reproduction device |
| JP2008167345A (en) * | 2007-01-04 | 2008-07-17 | Nec Saitama Ltd | Output method of sound signal, speaker system, portable device, and computer program |
-
1988
- 1988-08-20 JP JP20665788A patent/JPH0255500A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2001028799A (en) * | 1999-05-10 | 2001-01-30 | Sony Corp | Onboard sound reproduction device |
| JP2008167345A (en) * | 2007-01-04 | 2008-07-17 | Nec Saitama Ltd | Output method of sound signal, speaker system, portable device, and computer program |
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