JPS6016158Y2 - speaker network - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improvements in speaker networks used in multiway speaker systems.

The network used in the speaker system is designed to minimize interference between speaker units near the crossover frequency.

Frequency characteristics with a steep slope are required in order to quickly reduce the signal level in bands with high distortion levels outside the band of use, such as around the lowest resonance frequency, the high-frequency resonance range, and the divided resonance range.

Furthermore, in a speaker system, the amount of phase rotation must be minimized to improve the connection between each speaker unit and to level out the crossover frequency characteristics.

However, it is known that the frequency characteristics and the amount of phase rotation are inversely proportional, and the steeper the slope of the frequency characteristics, the larger the amount of phase rotation. There is a relationship in which improving one will worsen the other.

Conventionally commonly used speaker networks include:
There are -12dB10C4 and -6dB10ct.

Therefore, the -12dB10Ct network is
Focusing on frequency characteristics, the phase characteristics are sacrificed, and the -5 dB10ct network sacrifices the frequency characteristics in order to improve the phase characteristics.

The present invention has been developed in view of the above points, and is different from the conventional one.
The present invention aims to provide a speaker network that has better characteristics in both frequency characteristics and phase characteristics than a speaker network that has a slope of dB10ct.

Hereinafter, an explanation will be given based on an example with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of the present invention, in which 1 is an input terminal 2 connected to the output terminal of an amplifier (not shown), and 3 is a trap circuit connected in series with the filter. , 4 is a speaker, and 5 is a constant resistance reversible circuit for suppressing an increase in impedance of the speaker 4.

Therefore, the filter 2 has a cutoff frequency set outside the target frequency band and has a predetermined slope (for example, -12 dB10C1), and the cutoff frequency is moved outside the target frequency band. It is the same filter used in conventional speaker networks, except that it is

Further, the trap circuit 3 has a steeper slope than the filter 2, and by connecting it in series with the filter 2, it is possible to obtain a frequency characteristic having a steeper slope as a whole.

Therefore, among the signals applied to the input terminal 1, out-of-band signals are effectively attenuated, so that reproduced sound with less distortion can be obtained from the speaker 4, and when used in a multi-way speaker system. , defects such as mutual interference can be improved.

Figure 2 shows a specific example of the block diagram in Figure 1.
As a filter, an LC low-pass filter 8 consisting of a coil 6 and a capacitor 7 is used, and as a trap circuit 3, a series resonant circuit consisting of a capacitor 9, a resistor 10, and a coil 11 is used, and a parallel resonant circuit consisting of a capacitor 13, a resistor 14, and a coil 15 is used. A circuit combining 16 is used.

The series resonant circuit (2) is a constant resistance reversible circuit of the parallel resonant circuit (2).

The front Bc low-pass filter 8 has a cutoff frequency of approximately IKHz and a slope of -12 dB10C4, as shown by the dashed line A in FIG. Circuit 1 is
As shown by the dotted line in FIG. 3, it is configured to have a center frequency of approximately 1.3 KHz and a steeper slope than the pressure low-pass filter 8.

This slope can be easily changed by changing the value of the resistor 14.

Therefore, the civilian low-pass filter 1 and the trap circuit 1
The overall characteristics of the combination of
It has a cutoff frequency of 0H2 and a steep slope.

Incidentally, the two-dot chain line 2 in Figure 3 shows the characteristics of a low-pass filter used in the conventional network, which has a cutoff frequency of 500H2 and a slope of -12dB10ct, but as is clear from the figure, the network according to the present invention has a steeper slope.

Moreover, FIG. 4 shows the phase characteristics of the network shown in FIG. 2 according to the present invention, where the dashed line A indicates the amount of phase rotation of the pressure low-pass filter 8, and the dotted line indicates the amount of phase rotation of the trap circuit 3. .

As is clear from the figure, the amount of phase rotation of the main trap circuit is
Despite its steep slope, there are very few.

Therefore, the total amount of phase rotation between the LC low-pass filter 8 and the trap circuit 3 should be as shown by the solid line in FIG.
ct).

Particularly when used in a multi-way speaker system, phase rotation near the crossover frequency (500H2) becomes a problem, but the phase rotation of the network according to the present invention is smaller than that of the conventional 12 dB 10 ct network. stomach.

As mentioned above, the speaker network according to the present invention can obtain frequency characteristics with a steep slope and small phase rotation by combining a filter and a trap circuit, and is an optimal circuit for a speaker network. can be provided.

In addition, in the embodiment, the case where a low-pass filter and a trap circuit are combined is explained, but the same objective can be achieved by a combination of a bypass filter and a trap circuit, or a combination of a band-pass filter and a trap circuit. Ru.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing an embodiment of the present invention, Fig. 2 is a circuit diagram showing a specific example thereof, Fig. 3 shows the frequency characteristics of the circuit shown in Fig. 2, and Fig. 4 shows its phase characteristics. FIG. Explanation of main drawing numbers, 2...Filter, 3...
Trap circuit, 1...4C low pass filter.

Claims (2)

[Scope of utility model registration request] (1) A filter with a cutoff frequency set outside the target frequency band and a trap circuit connected in series with the filter and having a steeper slope than the filter, and the overall crossover frequency What is claimed is: 1. A speaker network having a cutoff frequency substantially equal to that of the filter, and a frequency characteristic having a steeper slope than the filter. (2) The speaker network according to claim (1), wherein the filter is a low-pass filter having a -12 dB 10 ct no slope.