JPS5947901B2 - stereo signal display device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a stereo signal display device, and more particularly to a stereo display device that can visually display the state of energy distribution of an audio signal.

In television broadcasting stations, radio broadcasting stations, etc., it is necessary to constantly check the state of the energy distribution of the audio signal to be transmitted in order to accurately broadcast the state of the sound stage. The state of the energy distribution is checked by drawing a Lissajous figure with an oscilloscope and judging the figure.

However, since the level frequency of the left and right channel signals of a stereo signal generally changes over time, the shapes of the left and right channel signals of a stereo signal generally change drastically, making it difficult to expect an accurate check.

Therefore, the present invention has been made in view of the above situation, and an object of the present invention is to provide a stereo display device with a novel configuration that can visually display the state of energy distribution including the spread and bias of stereo signals. The purpose is to

One embodiment will be described below with reference to the accompanying drawings.

First, the embodiment will be explained with reference to FIG. 1.1.
Reference numeral 2 indicates an input terminal for left and right channel signals, 4.5 indicates a left and right channel signal level indicator, respectively, and 6 indicates a summed signal level indicator for left and right channel signals.

The input terminals 1 and 2 each have a primary winding 9 of a transformer 7.8.
, 10 are connected, and each secondary winding 1 of the transformer 7.8
1.12 has left and right channel signal level indicators 4 and 5
are connected to each other via a cancellation circuit 13.

Here, when the left and right channel signals have the same phase and the same level, the canceling circuit 13 cancels both signals, and in particular, in the embodiment, the canceling circuit 13 cancels the left and right channel signals with each other.
The middle tap of each secondary winding 11.12 is grounded, and one end of each secondary winding 11.12 is connected to a pair of diodes 14.1 to the corresponding left and right channel signal level indicators 4, 5, respectively.
15, 16, and 17 are connected in series in the forward direction, and the other end of the secondary winding 12 of the transformer 8 is connected to the connection point of the diodes 14 and 15 via the diode 18.
The other end of the secondary winding 11 is connected to the diode 16 through a diode 19. It is configured by connecting to 17 connection points.

Further, in order to add the left and right channel signals in the adding circuit 20 and supplying the result to the added signal level indicator 6, the added signal level indicator 6 is connected to the left and right channel signal input terminals 1 through the adding circuit 2o. , 2.

Here, the adder circuit 20 is configured by connecting in parallel resistors 21 and 22 connected to each of the input terminals 1 and 2, and a common connection point on the output side is connected to the addition signal level indicator 6. are doing.

On the other hand, each level indicator 4. 5. 6 are each LED
They are arranged in an inverted T-shape on the display panel as shown in Figure 2.

That is, the left and right channel level indicators 4 and 5 are arranged on a horizontal line to the left and right, and the addition signal level indicator 6 is located in the middle of the line, that is, the left and right channel signal level indicators. It is arranged so as to branch out substantially perpendicularly from the separation point at 4°5.

According to the display device of the present invention having such a configuration, the state of the energy distribution of the stereo signal can be visually judged in the following manner.

l) When the left and right channel signals are in the same phase and level (
In the case of a monaural signal) Since both signals are canceled by the cancellation circuit 13, only the added signal level indicator 6 emits light as shown in FIG.

(Light emission is indicated by a black circle, and the same applies to the following cases.) However, even if the left and right channel signals are in the same phase, if there is a difference in their level, the difference will be displayed on the level indicator 4 or 5 is displayed.

2) When the left and right channel signals have opposite phases and the same level, the addition circuit 20 makes the sum of their signal levels zero, so the left and right channel signal level indicators 4 and 5 simultaneously emit light (the fourth (see figure).

3) When only the left or right channel signal is supplied, either the left or right channel signal indicators 4, 5 and indicator 6, which have the input signal, emit light.

Note that when only the left channel signal is supplied, the right channel signal level indicator 5 does not emit light because the diodes 19 and 17 are reverse biased, and the same applies when only the right channel signal is supplied. (Figure 5,
(See Figure 6).

4) When the left and right channel signals are of different types, both the left and right channel signal level indicators 4 and 5 and the addition signal level indicator 6 emit light (see FIG. 7).

In addition, in the above embodiment, each level indicator 4,
5. Needless to say, the number of light emitted from the 6 LEDs changes proportionally depending on the supplied signal level.

Therefore, according to such a stereo signal display device, when the left and right channel signals are in the same phase and at the same level, the input terminals of the left and right channel signals are connected through a cancellation circuit that cancels both signals. The left and right channel signals are displayed through left and right channel signal level indicators arranged to distribute each other in the left and right directions, and an adder circuit that adds the left and right channel signals. and an addition signal level display branched from the separation point of the left and right channel signal level indicators to extend substantially perpendicularly from the separation point of the left and right channel signal level indicators. Therefore, it is possible to directly check the state of the energy distribution of the audio signal by simply looking at the lighting conditions of the left and right channel signal level indicators and the level indicator of the added signal. It has a unique effect that allows you to objectively and easily and accurately judge the spread and bias of sound in a sound stage, which was previously impossible to do.

Therefore, if used for testing or parking at a broadcasting station, etc., it has the advantage of being able to easily determine whether the stereo signal to be broadcast is being transmitted correctly.Also, if used in addition to a normal playback device, the sound spreads out. It has the advantage of being able to enjoy the state of the energy distribution of the sound stage, including bias and three-dimensionality, visually as well as aurally.

It should be noted that the display device of the present invention is not limited to the above-mentioned display device, but may include, for example, a display device using a cathode ray tube, as long as the level indicators form an arrangement characteristic of the display device of the present invention.
Alternatively, a device using a liquid crystal, a pointer type meter, etc. may be used, and the point is to measure the left and right channel signal levels and the addition signal level independently, preferably vectorially or graphically as described above. Any device that has the function of displaying information may be used.

Further, although the above embodiment uses a transformer to configure the cancellation circuit, for example, as shown in FIG. 8, transistors 23 and 24 are used, or as shown in FIG. Of course, the canceling circuit may be configured using 30.

Note that in FIGS. 8 and 9, parts corresponding to those in FIG. 1 are given the same reference numerals.

Furthermore, as in the circuit shown in FIG. 9, a negative phase indicator 31 is provided, and left and right channel signals are supplied from input terminals 1 and 2 to this via an operational amplifier 32 and an operational amplifier 33 having a phase inversion function. It may also be displayed.

In addition, each level display device 4 in the level display device in this case. 5. 6.31 may be arranged in a cross pattern as shown in FIG. 10, for example.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram showing an embodiment of the present invention, FIG. 2 is a diagram showing the arrangement of level indicators of a display device of the same embodiment, and FIGS. 3 to 7 are a display device of the same embodiment. 8 is a circuit diagram showing another embodiment of the present invention, FIG. 9 is a circuit diagram showing still another embodiment of the present invention, and FIG. 10 is a display device of the same embodiment. FIG. 3 is a diagram showing the arrangement of level indicators in FIG. Explanation of symbols: 1, 2... Left and right channel signal input terminals, 4. 5. 6...Level indicator, 13
...Cancel circuit, 20... Addition circuit.

Claims (1)

[Claims] 1. Connected to the input terminals of the left and right channel signals via a cancellation circuit that cancels both signals when the left and right channel signals have the same phase and level, and Via left and right channel signal level indicators arranged to distribute left and right, and an adder circuit that adds the left and right channel signals,
A summation signal level indicator connected to the input terminals of the left and right channel signals and arranged in a branched manner extending substantially vertically above the separation point of the left and right channel signal level indicators. A stereo signal display device comprising: