JPH0682272B2 - Rhythm display device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rhythm display device used for a sound recorder such as a tape recorder, a record, a television, a radio, and a karaoke machine.

2. Description of the Related Art FIG. 3 shows a block diagram of a conventional rhythm display device.

In FIG. 3, 1 is an input terminal for inputting a signal, 2 is a band pass filter for extracting a low or high frequency signal in the signal, 3 is an integrating circuit for integrating the signal with a certain time constant, 4 Is for comparing two signals, and when one signal is larger than the other signal, a comparator circuit for generating a pulse signal, 5 is a volume for adjusting the level of the signal to be the input of the comparator circuit 4, and V-, V + are A display circuit 6 indicates a certain voltage value and displays the input signal.

Further, FIG. 4 shows signal waveforms at respective portions in FIG.

In FIG. 4, a is an input signal applied to the input terminal 1, b is an output signal of the band pass filter 2, c is an output signal of the integrator circuit 3, and d and e are waveforms of the output signal of the comparator circuit 4, respectively. , B indicates the voltage level set by the volume 5.

The operation will be described below with reference to FIGS.

The signal a applied to the input terminal 1 is input to the band pass filter 2, a low-frequency or high-frequency only signal b (in this case, a low-frequency only signal is shown) is extracted, and this signal Is input to the integrating circuit 3 and the signal is integrated to obtain a signal c. Further, in the comparison circuit 4, the voltage value set by the volume 5, A or B, and the signal c are compared, and when the signal c is larger than A or B, a pulse signal as shown by the signal d or e is output. (Where voltage value A
The signal output by (1) is d, and the signal output by the voltage value B is (e). ) The display circuit 6 performs display corresponding to the signals d and e. With the above configuration, it is possible to detect and display an impact sound such as a rhythm instrument included in the low frequency component, and thus, the rhythm in music can be displayed.

Problems to be Solved by the Invention However, in the above-mentioned conventional configuration, the signal d,
If the set value of the comparison voltage (such as A and B in FIG. 4) in the comparison circuit 4 changes like e, the output signal of the comparison circuit 4 also changes. Also, the comparison voltage is large,
Alternatively, when the level of the input signal is low, there is a drawback that the rhythm sound cannot be detected.

In view of the above problems, the present invention provides a rhythm display device capable of detecting and displaying a rhythm sound included in a music signal with a certain accuracy regardless of the level of the input signal.

Means for Solving the Problems In order to solve the above problems, the present invention relates to a bandpass means for extracting a high-frequency or low-frequency signal in a signal, and an integration of an output signal of the bandpass means. 1, the second integration means,
A differentiating means for detecting a rising edge of the output signal of the second integrating means; a comparing means for receiving the output signal of the differentiating means and the output signal of the second integrating means for comparing the magnitudes of the two signals; It is configured to have a gate unit that gates a signal output from the comparison unit, and a display unit that displays an output signal of the gate unit.

Operation According to the present invention, with the above configuration, first, the bandpass means extracts a signal in only the high range or the low range, and extracts a rhythm instrument component included in the high range or the low range. Particularly, in the high range, signals containing snare and cymbal type rhythm musical instruments, and in the low range, bass drum and bass type rhythm musical instrument sounds are extracted. The output signal of the bandpass means is branched into two and then input to the first and second integrating means having different time constants, and the energy of the signal is obtained. The output signal of the first integrating means is input to the differentiating means, the rising edge of the input signal is detected, and is input to the comparing means. The output signal of the second integrating means is also input to the comparing means. In the comparing means, the output signal of the differentiating means and the output signal of the second integrating means are compared, and when the output signal of the differentiating means is larger than the output signal of the second integrating means, it is positive or negative. A pulse signal is output. Since the output signal of the second integrating means is compared with the level of the input signal,
By comparing this signal with the output signal of the differentiating means which has detected the rising edge of the input signal, it is possible to accurately extract a signal (rhythm musical instrument sound) having a sharp rising edge according to the level of the input signal. Become.

The output signal of the comparison means is input to the gate means, where the input signal is gated at certain time intervals. As a result, it is possible to prevent malfunctions due to the sound of musical instruments other than the rhythm musical instrument. The output signal of the gate means is input to the display means, the amount corresponding to the input signal is displayed, and the rhythm display corresponding to the music signal can be accurately performed.

Embodiment One embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram of a rhythm display device according to an embodiment of the present invention.

In FIG. 1, 7 is an input terminal for inputting a signal, 8 is a band pass filter which passes only a high band or low band signal, 9 and 10 have different time constants, and the output signal of the band pass filter 8 is In the integrating circuit for integrating, the time constant of the integrating circuit 10 is set larger than the time constant of the integrating circuit 9. 11
Is a differentiating circuit for detecting the rising edge of the output signal of the integrating circuit 9, 12 is comparing the output signals of the differentiating circuit 11 and the integrating circuit 10,
When the output signal of the differentiating circuit 11 is larger than the output signal of the integrating circuit 10, a comparison circuit that outputs a pulse signal, 13 is an output signal of the comparison circuit 12, the first signal is passed, and a certain period from that signal A gate circuit that does not allow an output signal to pass during the period, and a sounding circuit 14 that generates a sound by using the output signal of the gate circuit 13 as a trigger.

Further, FIG. 2 shows signal waveforms at respective points in the block diagram which is one embodiment of the present invention shown in FIG. In FIG. 2, a is an input signal, b is an output signal of the band-pass filter 8 (in this case, a low-pass signal is passed), c is an output signal of the integrating circuit 9, and d is an output signal.
Is the output signal of the integrator circuit 10, and e is the output signal of the differentiator circuit 11, and the waveform of the output signal d of the integrator circuit 10 is shown overlaid with a broken line. Further, f is an output signal of the comparison circuit 12, and g is an output signal of the gate circuit 13.

Hereinafter, the present embodiment will be described with reference to the drawings.

The signal a input to the input terminal 7 is input to the band pass filter 8 and the signal b of only a certain band is extracted. As a result, the signal of the rhythm instrument is emphasized. The output signal b of the bandpass filter 8 has a different time constant (integrator circuit
10 is larger) The integrated signals c, d input to the integrating circuits 9 and 10
Is obtained, and the energy of the signal is obtained. Integrating circuit 9
The output signal c of is input to the differentiating circuit 11, and the rising edge of the signal is detected (signal e). The signals e and d are input to the comparison circuit 12 for comparison. If the signal e is larger than the signal d, the pulse signal f is output. Since the signal d takes a value proportional to the level of the input signal, and the signal e detects the rising edge of the signal, the comparison circuit 12 accurately determines the rhythm instrument sound whose rising edge is sharp regardless of the level of the input signal. It can be extracted well. This is the feature of this embodiment.

Next, the output signal c of the comparison circuit 12 is input to the gate circuit 13 and is gated and output at a certain time T (signal g). Here, the gate means that the first input pulse is passed as it is, and the input signal is not passed during the time T from that signal. By providing the gate circuit 13 in this way, it is possible to prevent malfunctions due to the influence of other musical instruments.

Then, the output signal g of the gate circuit 13 is input to the sounding circuit 14, and sound is generated by using this signal as a trigger.

As described above, according to the present embodiment, the rhythm component in the music signal can be accurately extracted regardless of the level of the input signal, and the rhythm can be displayed with high accuracy.

Further, in the present embodiment, the rhythm display means is a sounding circuit, but the same effect can be obtained by a light emitting circuit using an LED or the like, or a method of directly applying vibration to the human body instead of sounding. is there.

EFFECTS OF THE INVENTION The present invention includes band-passing means for passing only a high-frequency or low-frequency signal of an input signal, first and second integrating means for integrating the signal, and differentiating means for detecting the rising edge of the signal. Comparing two input signals, comparing means for outputting a positive or negative pulse signal when one signal is larger than the other signal, gate means for gate the input signal at a certain time, and By providing the display means for displaying in accordance with the quantity, the rhythm component signal contained in the signal can be extracted regardless of the level of the input signal, and the rhythm can be displayed accurately.

[Brief description of drawings]

FIG. 1 is a block diagram of a rhythm display device in one embodiment of the present invention, FIG. 2 is a signal waveform diagram showing the operation of each part of the embodiment of FIG. 1, FIG. 3 is a conventional block diagram, and FIG. The figure is a waveform diagram of a signal showing the operation of each part of the conventional example. 7 ... Input terminal, 8 ... Bandpass filter, 9, 10 ...
Integrator circuit, 11 …… differential circuit, 12 …… comparator circuit, 13 …… gate circuit, 14 …… sound circuit.

Claims (2)

[Claims] Claim: What is claimed is: 1. An input terminal for inputting a music reproduction signal, band pass means for extracting a signal of a rhythm musical instrument component of a high band or low band of the input signal, and an output signal of the band pass unit. Branching means, and first and second integrating the signals branched into two by the branching means with different time constants.
Comparing the output signal of the differentiating means with the differentiating means for detecting the rising of the output signal of the first integrating means, and the output signal of the second integrating means. The comparing means for generating a positive or negative pulse signal when the output signal of the second integrating means is larger than the output signal of the second integrating means, and the output signal of the comparing means are used as inputs, and the first input signal is passed, but thereafter within a fixed time. A rhythm display device comprising: gate means that does not pass an input signal; and display means that receives an output signal of the gate means and displays the signal. 2. The display means displays a sound, in correspondence with an input signal.
The rhythm display device according to claim 1, wherein display is performed by light or vibration.