【図面の簡単な説明】[Brief explanation of the drawing]
第１図Ａは車室内の前座席における音圧周波数特性、Ｂ
は後座席における音圧周波数特性、第２図は車載用音響
装置の再生系の一例を示す構成図、第３図は音場内にお
ける直接波と反射波との一例の様子を示す図、第４図は
聴取点での音圧の周波数特性を示す図、第５図は道路状
況および走行速度に応じた自動車の車内騒音のスペクト
ルを示す図、第６図は本考案の一実施例を示すブロン□
り図、第７図は第６図における第１の高域補正回路の
一例を示す回路図、第８Ａ図はスピーカのエネルギーレ
スポンスの特性図、第８Ｂ図は第７図の回路の補正周波
数特性図、第９図は第６図における走行マスキング補正
回路による周波数特性図、第１０図は第６図における第
２の高域補止回路の一例の回路図、第１１図は各車種Ａ
、 Ｂ毎の原信号ａ、第１の高域補正回路の出力ｂ、第
２の高域補正回路の出力Ｃの周波数特性図、第１２図は
乗員増加による高域レベルの低下の状態を示す周波数特
性図、第１３図は第６図における乗員数対応補正回路１
６Ｌ、１６Ｒの一例の回路図、第１４図はフロントドア
に取り付けられた左右一対のスピーカと聴取点との位置
関係を示す図、第１５図は第６図における可変利得器２
５Ｌ、２５Ｒの一例を示す回路図、第１６図は第６図に
おける前座席側の第１の高域補正回路および乗員数対応
補正回路を一体に構成した一例の回路図、第１７図は後
座席側の第１の高域補正回路および可変利得器を一体に
構成した一例の回路図、第１８図ないし第２０図は第６
図における表示手段の具体的構成を示す回路図、第２１
図はスピーカをリアパーセルトレイ上に配置した場合に
おける鏡像効果の原理を示す図、第２２図はスピーカを
リアパーセルトレイ上に配置した場合の後座席における
周波数特性を示す図、第２３図は低域カットを行なわな
い場合の車室内における定在波分布図、第２４図はその
周波数特性図、第２５図は後座席側のパワーアンプの周
波数特性を示す図、第２６図は低域カットを行なった場
合の車室内における定在波分布図、第２７図はその周波
数特性図、第２８図は後座席側Ａ１前座席側Ｂおよび低
音用Ｃの各パワーアンプの周波数特性を示す図、第２９
図は車室内におけるスピーカの取付位置を示す図である
。
主要部分の符号の説明、１０・・・・・・第１の高域補
正回路、１１・・・・・・走行マスキング補正回路、１
２・・・・・・前座席用スピーカの補正回路、１３・・
・・・・後座席用スピーカの補正回路、１５Ｌ、１５Ｒ
・・・・・・第２の高域補正回路、１６Ｌ、１６Ｒ・・
・・・・乗員数対応補正回路、１７Ｌ、１７Ｒ・・・・
・・ピーク・ディップ補正回路、２３Ｌ、２３Ｒ，２５
Ｌ、２５Ｒ・・・・・・可変利得器、３０・・・・・・
入力手段、３１・・・・・・表示手段。
１ ｌ ｌ １ ／６２１１．Ｉ？”””−−−−−−
［
ｌ イ４
一一−−−−−−−−−−−−−−’１１ １ｌ入力
「
幕１２図
問饗駅（Ｈｒ）Figure 1 A is the sound pressure frequency characteristic in the front seat of the vehicle interior, B
2 is a configuration diagram showing an example of a reproduction system of an in-vehicle audio device. FIG. 3 is a diagram showing an example of direct waves and reflected waves in a sound field. Figure 5 shows the frequency characteristics of the sound pressure at the listening point, Figure 5 shows the spectrum of noise inside a car depending on road conditions and driving speed, and Figure 6 shows the frequency characteristics of the sound pressure at the listening point. □
Figure 7 is a circuit diagram showing an example of the first high-frequency correction circuit in Figure 6, Figure 8A is a characteristic diagram of the energy response of the speaker, and Figure 8B is a correction frequency characteristic of the circuit in Figure 7. 9 is a frequency characteristic diagram of the driving masking correction circuit in FIG. 6, FIG. 10 is a circuit diagram of an example of the second high frequency correction circuit in FIG. 6, and FIG. 11 is a diagram for each vehicle type A.
, a frequency characteristic diagram of the original signal a for each B, the output b of the first high frequency correction circuit, and the output C of the second high frequency correction circuit, FIG. Frequency characteristic diagram, Figure 13 is the number of occupant correction circuit 1 in Figure 6.
A circuit diagram of an example of 6L and 16R, FIG. 14 is a diagram showing the positional relationship between a pair of left and right speakers attached to the front door and a listening point, and FIG. 15 is a diagram showing the variable gain unit 2 in FIG. 6.
5L and 25R, FIG. 16 is a circuit diagram of an example in which the first high-frequency correction circuit on the front seat side and the correction circuit corresponding to the number of occupants in FIG. 6 are integrated, and FIG. 17 is a circuit diagram showing the rear An example of a circuit diagram in which the first high-frequency correction circuit and the variable gain device on the seat side are integrated, and FIGS. 18 to 20 are shown in FIGS.
Circuit diagram showing the specific configuration of the display means in the figure, No. 21
The figure shows the principle of the mirror image effect when the speakers are placed on the rear parcel tray, Fig. 22 shows the frequency characteristics in the rear seats when the speakers are placed on the rear parcel tray, and Fig. 23 shows the frequency characteristics in the rear seat when the speakers are placed on the rear parcel tray. Fig. 24 is a diagram showing the standing wave distribution in the vehicle interior when low frequency cut is not performed, Fig. 24 is a diagram showing its frequency characteristics, Fig. 25 is a diagram showing the frequency characteristics of the power amplifier on the rear seat side, and Fig. 26 is a diagram showing the frequency characteristics of the power amplifier on the rear seat side. Figure 27 is a diagram showing the distribution of standing waves in the vehicle interior when the power amplifier is used. 29
The figure is a diagram showing the mounting position of the speaker in the vehicle interior. Explanation of symbols of main parts, 10...First high frequency correction circuit, 11...Travel masking correction circuit, 1
2...Front seat speaker correction circuit, 13...
...Rear seat speaker correction circuit, 15L, 15R
...Second high frequency correction circuit, 16L, 16R...
... Correction circuit corresponding to the number of passengers, 17L, 17R ...
...Peak dip correction circuit, 23L, 23R, 25
L, 25R...Variable gain unit, 30...
Input means, 31...Display means. 1 l l 1 /6211. I? ”””---
[l I4 11--------------'11 1l input
`` Maku 12 Zumongyo Station (Hr)