JP2505154Y2 - Signal switching circuit - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a signal switching circuit used in an audio mixer.

[0002]

2. Description of the Related Art Effect mixers have been used for audio mixers.
A circuit that extracts the send signal is added, and this effect send signal adds an effect to the output signal,
FIG. 3 for monitoring and the like shows a circuit diagram of a conventional effect send circuit of a mixer. Generally, the effect send signal sent from each channel of the mixer is taken out from the post stage (post) of the channel fader, but depending on the usage situation, you may want to take it out from the front stage (pre),
The mixer of the middle and upper unit is provided with a switch for switching between pre / post.

In FIG. 3, the volume of an input signal is adjusted by a channel fader 11, amplified by a buffer amplifier 12, and then input to a pan pot (panoramic potentiometer) 13 as well as a post of a pre / post switch 14. ) Input. Also,
Input signal is pre / post switch 14 pre (PRE)
Input to the side.

The pan pot 13 sets the stereo localization of L and R, and its output is sent to each of the L channel bus and the R channel bus.

On the other hand, the effect send signal taken out from the common side of the pre / post switch 14 is adjusted in volume by the variable resistor 15 and sent to the effect send bus B ₁ .

A plurality of sets of these circuits are connected to the L channel bus, the R channel bus, and the effect send bus B ₁ for each input channel.

In the output stage (master section), the L channel signal is sent from the L channel bus to the L channel line via the summing amplifier 16, and the R channel signal is sent from the R channel bus via the summing amplifier 17 to the R channel signal. Are sent to the R channel line. Then, an effect send signal is sent from the effect send bus B ₁ via the summing amplifier 18 to an effect send line E ₁ connected to a predetermined effector (e.g., echo) or a monitor speaker.

In the circuit described above, when the pre / post switch 14 is on the post side, an effect send signal is sent to an effector such as an echo, and when it is on the pre side, monitoring is performed.

[0009]

By the way, the pre / post switch 14 provided in each input channel is rarely different for each channel like the pre side or the post side, and all the channels are all set to the pre side. Or, the post side is generally used. Therefore, all the pre / post switches 14 must be switched in order to set the effect send signals of the multi-channel mixer of several tens of channels (for example, 24 channels, 32 channels) to the pre side or the post side all at once. The problem is that it is complicated. In addition, if these are switched all at once by relay or the like, there is a problem that the cost becomes high.

Therefore, the present invention has been made in view of the above problems, and an object thereof is to provide a signal switching circuit for facilitating the operation and reducing the cost of the apparatus.

[0011]

SUMMARY OF THE INVENTION The above problem is that the stereo localization is set after the signal amount of the input signal is adjusted by the adjusting means, and the effect of the other system is set either before or after the adjusting means. A signal switching circuit comprising a predetermined number of input parts from which a send signal is taken out and an output part for outputting the stereo-localized stereo signal and the effect send signal to a predetermined channel line, This is solved by providing a switch means for selecting the extraction of the effect send signal from the front stage or the rear stage of the adjusting means in the input section.

[0012]

As described above, when the effect send signal is taken out from the front stage or the rear stage of the adjusting means, it is switched and output by the switch means provided in the output section. That is, by providing the switch unit at the output unit, even if a plurality of input units are connected, the effect send signal can be taken out from the front stage or the rear stage of the adjusting unit by a single switching.

As a result, the operation can be facilitated and the cost of the device can be reduced.

[0014]

1 is a block diagram of the first embodiment of the present invention. FIG. 1 shows a signal switching circuit used in an audio mixer.

The signal switching circuit 20 shown in FIG.
Channel bus, R channel bus, and effects
The input unit 21 and the output unit 22 are separated by the send buses B ₁ and B _2.
It is roughly divided into.

The input section 21 is connected to an input terminal of a pan pot 26 of a stereo localization circuit through an input terminal 23 connected to the equalizer circuit of the preceding stage, a channel fader 24 and a buffer amplifier 25. And the pan pot 26
The two output terminals of are connected to the L channel bus and the R channel bus, respectively.

The output terminal of the buffer amplifier 25 is connected to the effect send bus B ₁ via the variable resistor 27a, and the input terminal 23 is connected to the effect send bus B ₂ via the variable resistor 27b. The two variable resistors 27a and 27b are two linked variable resistors.

A plurality of sets of the above circuits are connected to the L channel bus, the R channel bus, and the effect cent buses B ₁ and B ₂ .

On the other hand, the output section 22 is connected to the L channel line from the L channel bus via the summing amplifier 28, and the summing amplifier 29 from the R channel bus.
Is connected to the R channel line via.

Further, the effect send bus B ₁ is a post (P) of the pre / post switch 30 which is a switch means.
OST) terminal, effect send bus B ₂
Is connected to the PRE terminal. Then, the common terminal of the pre / post switch 30 is connected to the effect send line E ₁ connected to a predetermined effector via the summing amplifier 31.

In such a signal switching circuit 20, first, in the input section 21, the volume of the input signal input to the input terminal 23 is adjusted by the channel fader 24, the volume is amplified by the buffer amplifier 25, and then the pan pot 26. The stereo localization is adjusted by to produce a stereo signal, which is sent to the L and R channel buses.

On the other hand, the post signal of the effect send signal extracted from the subsequent stage of the channel fader 24 (output of the buffer amplifier 25) is adjusted in volume by the variable resistor 27a and sent to the effect send bus B ₁ . Also, pre-signal effect send signal taken from the preceding channel fader 24 (input terminal 23) is sent is the volume adjusted to effect send bus B ₂ the variable resistor 27b.

In the output section 22, the signals of the L channel bus are mixed by the summing amplifier 28 and the stereo L signal is output.
A channel signal is obtained and the R channel bus signal is mixed by the summing amplifier 29 to obtain a stereo R channel signal.

In addition, the effect send buses B ₁ and B ₂
The post signal and the pre signal of the effect send signal in are switched by the pre / post switch 30,
It is mixed by the samink amplifier 31 and sent to a predetermined effector. For example, with the switch 30 set to the pre-terminal side, the input signal input to each channel can be monitored by switching once.

As described above, since the pre / post switch 30 is not provided for each channel but is collectively switched by the output section 22, the operation is facilitated even with a mixer of several tens of channels, and the parts The number of points can be reduced and the cost of the device can be reduced.

Next, FIG. 2 shows a block diagram of a second embodiment of the present invention. The signal switching circuit 20 of FIG. 2 is for outputting the effect send signal in stereo, and has effect send buses B ₃ and B ₄ added to the circuit of FIG. That is, the effect send buses B ₁ and B ₃ are post signal buses, and the buses B ₂ and B ₄ are pre signal buses.

In this case, two effect send pan pots 32 and 33 are provided at the subsequent stages of the variable resistors 27a and 27b, respectively, and a post signal is sent from the pot 32 to the effect send buses B ₁ and B ₃ . The pre signal is sent from the pot 33 to the effect send buses B ₂ and B ₄ .

Further, the pre / post switch 30a switches the post signal or the pre signal from the effect send buses B ₁ and B ₂ , and mixes them by the summing amplifier 31a and outputs them. The pre / post switch 30b interlocked with the pre / post switch 30a (2 series of pre / post switch) switches the signal post or pre-signal from the effects send buses B _3, B _4, mixes with summing amplifier 31b Output.

That is, a stereo effect send signal is sent out between the effect send lines E ₁ and E ₂ , and the effect send pan pots 32 and 3 are provided.
In 3, the stereo localization of the post signal or the pre signal is set.

As described above, even in the case of stereo output, by switching the post signal and the pre signal with the two series of pre / post switches, the operation can be facilitated and the cost of the device can be reduced. .

[0031]

As described above, according to the present invention, the effect send signal is output in monaural or stereo by switching the effect send signal by the switch means provided in the output section and extracting it from the front stage or the rear stage of the adjusting means. Even in this case, the operation can be facilitated and the cost of the device can be reduced by reducing the number of parts.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a first embodiment of the present invention.

FIG. 2 is a configuration diagram of a second embodiment of the present invention.

FIG. 3 is a circuit diagram of an effect send circuit of a conventional mixer.

[Explanation of symbols]

 20 signal switching circuit 21 input section 22 output section 23 input terminal 24 channel fader 25 buffer amplifier 26 pan pot 27a, 27b variable resistor 28, 29, 31, 31a, 31b summing amplifier 30, 30a, 30b pre / post switch 32, 33 Effect Send Pan Pot

Claims (1)

(57) [Scope of utility model registration request] 1. The stereo localization is set after the signal amount of the input signal is adjusted by the adjusting means, and the effect of another system is set from either the front stage or the rear stage of the adjusting means.
A signal switching circuit comprising a predetermined number of input sections from which a send signal is taken out and an output section for outputting the stereo-localized stereo signal and the effect send signal to a predetermined channel line, wherein the output section has the input A signal switching circuit having a switch means for selecting whether to take out the effect send signal from the front stage or the rear stage of the adjusting means.