JPS631353Y2 - - Google Patents

Description

[Detailed explanation of the invention] This invention allows the output of multiple keyboard instruments to be
When mixing and amplifying each channel, such as the right sound, using one expression pedal,
The present invention relates to a mixing amplification device for an electronic musical instrument in which a path that allows each channel to be controlled in volume in common and a path that allows each channel to be individually controlled can be switched and connected.

Traditionally, multiple keyboard instruments are placed around the performer,
A mixing amplification device for an electronic musical instrument that appropriately mixes each output is known. Figure 1 shows one example of this, a keyboard instrument.
The output of KB1 is connected to the input terminal IN of the mixing amplifier MXA.
Attenuator ATT, sound quality adjustment circuit TNC, mixing amplification circuit MX, intermediate amplifier AMP, main volume adjuster
There are multiple output terminals OUT to the main amplifier connected to the subsequent stage via the MFD. Output terminal OUT
-L is the left side sound, OUT-R is the right side sound, OUT-E is the echo sound, and OUT-F/B is the self-playing check sound terminal. Further, in the mixing amplifier circuit MX, the outputs of other keyboard instruments such as KB2 are mixed. When controlling the output volume of this device using the expression pedal EXP, conventionally only the expression pedals provided for each keyboard KB could be used individually. When three or four keyboard instruments are installed around a performer, it is practically impossible to control the volume by operating each expression pedal simultaneously or individually while operating the keyboard. The performers were dissatisfied with the sounds that were coming out of the speakers.

The purpose of the present invention is to improve the above-mentioned drawbacks, and when the output of multiple keyboard instruments is mixed and amplified for each channel such as left tone and right tone, each channel can be amplified by one expression pedal. It is an object of the present invention to provide a mixing amplification device for an electronic musical instrument that can switch and connect a path that can control the volume in common and a path that can control the volume individually.

Embodiments of the present invention shown in the drawings will be described below. In the circuit diagram shown in FIG. 2, the same symbols as in FIG. 1 indicate the same things. VCA represents a voltage-controlled amplifier as a variable amplification stage, and its control terminals are collectively connected to a voltage source +B via a variable resistor VR that is operated in conjunction with the expression pedal EXP. SW-A, SW-B, SW-C, SW
-D is an interlocking switching switch, and when it is connected to its OFF side terminal, the common control of the present invention is not performed, but individual control is performed as in the conventional case, and this signal path is referred to as the first path. When each switch is connected to the ON side terminal, it is commonly controlled through a second path consisting of a mixing amplifier circuit and a variable resistor. In other words, the variable resistor VR is linked to the operation of the expression pedal EXP to increase the volume, increasing the control voltage for the voltage-controlled amplifier VCA, for example, and applying a large output from the output terminal to the subsequent stage, thereby increasing the output of each keyboard instrument. are commonly controlled.

Note that FIG. 3 shows an example in which a photocoupler PHC is used as a specific example of the voltage-controlled amplifier VCM.
In Figure 3, LED is a light emitting diode, PT is a light receiving transistor, the input side of the light receiving transistor PT is connected to a mixing circuit, and the output side is an intermediate amplifier AMP.
is connected to. expression pedal
When EXP is depressed to produce a loud volume, the light emitting diode LED emits enough light and the resistance value across the photodetector transistor PT decreases, reducing the amount of signal attenuation and applying a large output to the main amplifier. can do.

In the configuration shown in Figure 2, if the interlocking switching switch is changed to an individual switching type and switched to the ON side and OFF side separately, there will be a second path that can be controlled for each channel, and a first path that is not commonly controlled. It is a mixing amplification device consisting of.

In this way, the present invention provides a variable amplification path in which the outputs of a plurality of keyboard instruments are commonly controlled according to only one expression pedal device;
By providing a path that is not commonly controlled, by using the path that is commonly controlled, when the outputs of multiple keyboard instruments are mixed and input into the variable amplification path, either artificially or automatically, Expression expressions can be made common to each channel, making it easy to improve performance effects.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the configuration of a conventional mixing amplification device.
FIG. 2 is a block diagram showing an embodiment of the present invention, and FIG. 3 is a circuit diagram showing a specific example of the voltage controlled amplifier shown in FIG. KB1, KB2...Keyboard instrument, MXA...Mixing amplifier, MX...Mixing circuit, AMP...Intermediate amplifier, OUT...Output terminal to main amplifier, EXP...
Expression pedal, VCA...Voltage controlled amplifier, SW-A, SW-B, SW-C, SW-
D...Interlocked switching switch.

Claims (1)

[Scope of Claim for Utility Model Registration] A mixing amplification device for an electronic musical instrument that mixes and amplifies the outputs of multiple keyboard-playing instruments for each channel, such as left tone and right tone, and outputs it to an output terminal. Equipped with an expression pedal, each channel has a first
path, another mixing amplification circuit, and a second path that outputs to an output terminal via a variable amplification stage that is commonly controlled for each channel by the expression pedal. A mixing amplification device for an electronic musical instrument, comprising a switching switch for switching input to either of the first and second paths.