JPH11177363A - Mixer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mixer loaded with a howling prevention device so that sound quality of a line signal remains unchanged by providing the howling prevention device where a second bus is connected to an input side and a first bus is connected to an output side. SOLUTION: In a howling prevention device 22, a howling bus 20 is connected to the input side while the output signal of the howling prevention device 22 is mixed by a master bus 10. When a changeover switch 1 is changed over to a contact point A, a changeover switch 2 is changed over to a contact point B and a changeover switch N is changed over to the contact point A, a line signal inputted to an input terminal 1 passes through a channel fader 1, and is sent to the master bus 10 through the changeover switch 1, then outputted to an adder 12 from the master bus 10. Since the line signal inputted to the input terminal 1 does not pass through the howling prevention device 22, sound quality of the line signal inputted to the input terminal 1 is prevented from changing by the howling prevention device 22.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a mixer,
More particularly, the present invention relates to a mixer capable of preventing the occurrence of howling.

[0002]

2. Description of the Related Art Generally, a microphone or musical instrument (synthesizer, electric guitar, or the like) is connected to an input terminal of a mixer, and a microphone signal or a line signal is input to the mixer. Mixing and outputting to a power amplifier as an audio signal, amplifying the audio signal by the power amplifier, outputting the amplified signal to a speaker, and emitting sound or musical sound to space based on the audio signal by the speaker. It has been known that howling occurs when the level of a microphone signal is too high.

Conventionally, a so-called howling prevention device has been used to prevent such howling from occurring.

The anti-howling device is, for example, a process for attenuating howling frequency components to prevent the occurrence of howling, or the frequency at which the howling occurs is determined by the distance between the microphone and the speaker. Therefore, a process of electrically changing the distance between the microphone and the speaker is performed to prevent the occurrence of howling.

As described above, since the howling prevention device performs a process of attenuating a frequency component in which howling occurs, an audio signal that has passed through the howling prevention device is not subjected to the howling prevention device. The sound quality was to be changed as compared with the audio signal.

[0006] Here, howling occurs only when a microphone is used, and does not occur due to line input.

However, a conventional mixer equipped with a howling prevention device has a circuit configuration in which an audio signal obtained by mixing microphone signals and line signals of all channels passes through the howling prevention device.

[0008] For this reason, a line signal in which no howling occurs also passes through the howling prevention device, and there is a problem that the sound quality of the line signal changes.

[0009]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and has as its object to prevent the sound quality of a line signal from being changed. It is an object of the present invention to provide a mixer equipped with such a howling prevention device.

[0010]

According to a first aspect of the present invention, there is provided an input terminal for inputting an external signal, and switching means connected to the input terminal. A first bus connected when the switching means is switched to the first state, and a second bus connected to the second bus when the switching means is switched to the first state.
A second bus connected when the state is switched to the state described above, output means for outputting a signal of the first bus, the second bus connected to an input side, and the first bus Has an anti-howling device connected to the output side.

Therefore, according to the first aspect of the present invention, when a line signal is input to the input terminal, the line signal is prevented from passing through the howling prevention device. Therefore, the sound quality of the line signal input to the input terminal is not changed by the howling prevention device.

Here, the switching between the first state and the second state by the switching means may be performed, for example, by changing the input level of the input terminal as in the second aspect of the present invention. An input level setting means for setting may be provided, and the switching means may be switched to the first state or the second state in accordance with the input level set by the input level setting means.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of a mixer according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a block diagram showing an embodiment of a mixer according to the present invention.

This mixer has input terminals 1 to N
N (N is a positive integer) input terminals, N amplifiers 1 to N connected corresponding to these N input terminals, respectively, and these N amplifiers Correspondingly connected channel faders 1
N channel faders up to a channel fader N, N changeover switches 1 to N connected to the N channel faders, respectively, and a master bus 10
, An adder 12 connected to these N switches, a master fader 14 connected to the adder 12, a master amplifier 16 connected to the master fader 14, and a connection to the master amplifier 16. The output terminal 18 is connected to the input terminal thereof via a mixing bus (hereinafter, referred to as a “howling bus”) 20, and its output is connected via a master bus 10. And an anti-howling device 22 to which the adder 12 is connected.

That is, the mixer includes a howling bus 20 connected to the input side of the howling prevention device 22, and the output signal of the howling prevention device 22 is mixed with the master bus 10.

Further, changeover switches 1 to N
Has a contact A and a contact B, respectively, and the changeover switches 1 to N can switch between the contact A and the contact B independently of each other. Then, the changeover switches 1 to N are set to the contact A
In this case, the channel faders 1 to N and the master bus 10 are connected via the changeover switches 1 to N.
On the other hand, when the changeover switches 1 to N are switched to the contact B, the changeover switches 1 to N
, The channel faders 1 to N and the howling bus 20 are connected.

In the above configuration, as shown in FIG.
A line signal is input to the input terminal 1, a microphone signal is input to the input terminal 2, and a line signal is input to the input terminal N. The changeover switch 1 is switched to the contact A, the changeover switch 2 is switched to the contact B, It is assumed that the changeover switch N is switched to the contact A.

In this case, the line signal input to the input terminal 1 is transmitted to the master bus 10 via the changeover switch 1 after passing through the channel fader 1, and the line signal is input from the master bus 10 to the adder. 12 is output.

Accordingly, since the line signal input to the input terminal 1 does not pass through the howling prevention device 22, the sound quality of the line signal input to the input terminal 1 is not changed by the howling prevention device 22. .

Similarly, the line signal input to the input terminal N is sent to the master bus 10 via the changeover switch N after passing through the channel fader N, and from the master bus 10 to the adder 12. Is output.

Accordingly, since the line signal input to the input terminal N does not pass through the howling prevention device 22, the sound quality of the line signal input to the input terminal N is not changed by the howling prevention device 22. .

On the other hand, the microphone signal input to the input terminal 2 is sent to the howling bus 20 via the changeover switch 2 after passing through the channel fader 2, and from the howling bus 20 to the howling prevention device 22. Is entered. The microphone signal input to the anti-howling device 22 is processed by the anti-howling device 22 to prevent the howling from occurring.
It is sent to 0 and output from the master bus 10 to the adder 12.

Therefore, since the microphone signal input to the input terminal 2 passes through the howling prevention device 22, it is possible to prevent the occurrence of howling due to the microphone input.

Here, the changeover switches 1 to N
The switching operation between the contact A and the contact B in is, for example,
As shown in FIG. 2, a changeover switch 1
To the changeover switch N, a selection button 102 for the contact A and a selection button 104 for the contact B are provided, and the selection button 102 for the contact A and the selection button 10 for the contact B are provided.
4, the changeover switch 1 to the changeover switch N may be configured to be arbitrarily operable manually, and the operator may manually switch the contact A and the contact B appropriately.

Generally, a mixer has a pad
A level setting means for setting the input sensitivity of an input terminal called a switch is provided.

When a high-level line signal is input as an input signal, the input sensitivity of the input terminal is reduced. When a low-level microphone signal is input as an input signal, the input terminal is reduced. Is set by a pad switch (level setting means) so as to increase the input sensitivity of.

When the input level of the pad switch (level setting means) is set to a low level, the input signal is a line signal, so that the howling prevention device 22 is not interposed. When the set level of the (level setting means) sets the input sensitivity to be high, the changeover switch is interlocked with the pad switch (level setting means) so that the howling prevention device 22 which is the input signal of the microphone signal is interposed. FIG. 3 shows an example in which the switching is automatically performed.

In FIG. 3, pad switches 301-301
The pad switch 30N sets the input sensitivity of the amplifiers 1 to N and is a known technique.

The pad switches 301 to 30N further include changeover switches 1 to N
Are also switched in conjunction with each other, and are connected to the contact A when the input sensitivity is set low, and are connected to the contact B when the input sensitivity is set high. .

[0031]

Since the present invention is constructed as described above, the present invention has an excellent effect that it is possible to provide a mixer equipped with a howling device which does not change the sound quality of a line signal. Play.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an example of an embodiment of a mixer according to the present invention.

FIG. 2 is a schematic diagram illustrating a main part of an operation panel provided with a selection button for a contact A and a selection button for a contact B corresponding to the changeover switches 1 to N, respectively;

FIG. 3 shows an example of a configuration in which a switching operation between a contact A and a contact B in a changeover switch 1 to a changeover switch N is automatically switched in accordance with a type of a signal input to input terminals 1 to N; It is a block block diagram.

[Explanation of symbols]

 Reference Signs List 10 master bus 12 adder 14 master fader 16 master amplifier 18 output terminal 20 howling bus 22 howling prevention device 100 operation panel 102 contact A selection button 104 contact B selection button 200 detection means 202 control means

Claims (2)

[Claims] An input terminal for inputting a signal from the outside, a switching means connected to the input terminal, a first bus connected when the switching means is switched to a first state, A second bus connected when the switching unit is switched to the second state; an output unit that outputs a signal of the first bus; and a second bus connected to an input side. And a howling prevention device, wherein the first bus is connected to an output side. 2. The mixer according to claim 1, further comprising: input level setting means for setting an input level of the input terminal, wherein the first level is set in accordance with the input level set by the input level setting means. A mixer for switching the switching means to a state or the second state.