JPH0435697B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION A. Field of Industrial Application The present invention relates to a device that samples musical tones (hereinafter referred to as musical tones) from a musical instrument player and measures their tempo (that is, the number of beats per unit time).

B. Summary of the Invention The present invention is a musical tempo measurement device that collects musical tones using a microphone, converts the musical sound waveform into pulses, measures and averages the pulse time intervals, and then converts the obtained pulse interval data into tempo data and displays it. , using an instrument played by the performer himself,
You can check your own sense of rhythm or tempo.

C. Prior Art Conventionally, a metronome with a tap function has been known as a device for checking a performer's own sense of tempo. That is, the metronome is equipped with a mechano-electric transducer element that is tapped continuously with a fingertip or the like according to the tempo sense, and the tempo is determined by measuring the interval between hits.

D. Problems to be solved by the invention However, the conventional tap method has the following problems. In other words, since the tempo is measured by repeated strikes with the fingertips, etc., the sensation is different from that of an actually used musical instrument (for example, a piano), and it is difficult to measure the tempo faithfully and accurately.

Also, when using it in music classes, students should go out of their way to
It was inconvenient to have to check the tempo using a metronome with taps while away from the instrument. It would be extremely convenient for the teacher if the tempo could be measured remotely using the instrument the student is using, but with the tap method, remote measurement was not possible.

E Means for Solving Problems The present invention aims to solve the above problems of the prior art and has the following configuration.

In other words, an acousto-electric transducer (for example, a microphone) that collects musical tones and converts them into electrical waveform signals, a waveform shaper that shapes the electrical waveform, and an electrical waveform with an amplitude greater than a predetermined value (i.e., a wave peak corresponding to a beat). a comparator that converts into pulses, a pulse interval measurement circuit that measures the time interval between adjacent pulses, an averaging circuit that averages multiple consecutive pulse interval data, and the obtained averaged pulse interval data. is the tempo data (for example, the number of pulses per minute, which is proportional to the reciprocal of the pulse interval)
The configuration consists of a tempo conversion circuit that converts the tempo data to , and a display element that displays the tempo data. This made it possible to measure tempo remotely using sound as a medium. It is extremely convenient compared to the conventional tap method using mechanical input.

F. Embodiments Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a circuit block diagram of a musical tone tempo measuring device. Reference numeral 1 denotes a microphone that collects musical sounds emitted from musical instruments and converts them into electrical waveform signals a. Electrical waveform signal a is shown in FIG. 2a. Each peak corresponds to a beat. Reference numeral 2 denotes a waveform shaper which inputs the electrical waveform signal a, and removes high frequency components and noise from this waveform to obtain an electrical waveform signal b. The waveform shaper 2 is composed of, for example, a low-pass filter. Electrical waveform signal b is shown in FIG. 2b. Reference numeral 3 denotes a comparator to which the electric waveform signal b is input, and also a predetermined threshold value V ₀ set by resistance division. The threshold value V ₀ is shown in FIG. 2b. Compare the voltage value of signal b and threshold V ₀ ,
The peak of the signal exceeding the threshold value V ₀ is converted into a rectangular pulse c. Pulse c is shown in FIG. 2c. 4 is a pulse interval measuring circuit which inputs the pulse train c and measures the time intervals of adjacent pulses (for example, t ₁ , t ₂ , t ₃ etc. shown in FIG. 2 c, which are the rising time intervals of the pulses).
Measures and outputs pulse interval data. Reference numeral 5 denotes a clock pulse generator, which is composed of, for example, a crystal oscillator, and supplies clock pulses to the pulse interval measuring circuit 4. The higher the frequency of the clock pulse, the more accurate the pulse interval measurement will be. That is, the pulse interval measuring circuit 4 is constituted by, for example, a decimal counter that is set by the rising edge of the pulse c, and measures the pulse time interval by counting the number of clock pulses supplied by the clock pulse generator 5.
We are measuring t ₁ , t ₂ , and t ₃ . 6 is an averaging circuit and pulse interval data (t ₁ , t ₂ , t ₃ ,...)
input and output their average value. Reference numeral 7 denotes a beat data input circuit, which controls the averaging circuit 6. That is, when the time signature data input circuit 7 inputs that the musical tone has four beats, the averaging circuit 6 averages four pulse interval data and outputs the averaged data. As a result, variations within one bar are averaged out, and stable tempo data can be obtained. In other words, latch display is possible. Note that input to the time signature data input circuit is performed using the numeric keypad 15. Input data is displayed by a display element. 8 is a tempo conversion circuit which inputs the averaged pulse interval data, calculates and outputs tempo data (for example, the number of beats per minute, which is proportional to the reciprocal of the pulse interval data). Reference numeral 9 denotes a display element driving circuit which inputs tempo data and decodes it so as to display it in, for example, seven segments. A display element 10 displays the decoded tempo data on a liquid crystal display consisting of, for example, seven segments. At the same time, time signature data is also displayed.

FIG. 3 is an external view of a musical tone tempo measuring device, which also serves as a metronome. Figure a is a front view, and figure b is a side view. In FIG. b, 11 is a power switch. In Figure a, 12 is a mode selection key (hereinafter simply referred to as a mode key). First, when the mode key is pressed once, the metronome tempo setting mode is selected, and the tempo number display 13 and time signature display 14 of the display element 10 flash. In this state, operate the numeric keypad 15 to set the desired tempo number (usually 40
~208/min) and the number of beats (e.g. 3
(time signature, quadruple time signature, etc.) are set in sequence using 16 set keys. Next, when the mode key 12 is pressed again, the metronome mode is set, and in this state, the start/stop key 17 is operated to execute metronome operation. Metronome is on speaker 18
The metronome is executed based on the tempo and beat input previously set by either the sound by the lamp 19 or the light by the lamp 19.

Now, when the mode key 12 is pressed again, the tone tempo measurement mode is selected next. At this time, time signature data or other time data to be input into the time signature data input circuit can be set in advance and displayed on the time signature display 14. Now, when the start stop key 17 is pressed in this state, musical tone tempo measurement is executed and the measurement result is shown on the tempo display 13. Since the tempo is measured by collecting sound with the microphone 1, remote measurement is possible.

Next, when the mode key 12 is pressed again, the mode shifts to a tempo reproduction mode in which the metronome is reproduced according to the tempo data that has just been measured. Therefore, the user can practice playing musical tones in accordance with a metronome that faithfully reproduces tempo data input by playing the instrument by oneself or by an instructor, which is useful for developing a sense of tempo.

G. Effects of the Invention The present invention is configured to remotely and directly collect musical sounds using a microphone, measure the tempo, display it, and preferably reproduce it using a metronome. It is extremely practical. Furthermore, since remote measurement is possible, the teacher can easily check the sense of tempo of each student even when used in a large classroom.

[Brief explanation of drawings]

FIG. 1 is a circuit block diagram of the musical tone tempo measuring device, FIGS. 2 a to 2 c are waveform diagrams, and FIGS. 3 a and b are external views of the musical tone tempo measuring device. DESCRIPTION OF SYMBOLS 1...Microphone, 2...Waveform shaper, 3...Comparator, 4...Pulse interval measurement circuit, 5...Clock pulse generator, 6...Averaging circuit, 7...Beat data input circuit, 8...Tempo conversion circuit, 9...Display Element drive circuit, 10...display element, 15...numeric keypad.

Claims (1)

[Scope of Claims] 1. An acousto-electrical transducer that collects musical tones and converts them into electrical waveform signals, a waveform shaper that shapes the electrical waveform, and a comparator that converts the electrical waveform having an amplitude greater than a predetermined value into pulses. , a pulse interval measurement circuit that measures the time interval between adjacent pulses, an averaging circuit that averages multiple pulse time interval data, and a tempo conversion that converts the obtained averaged pulse time interval data into tempo data. A musical tone tempo measurement device consisting of a circuit and a display element that displays tempo data. 2. The musical tone tempo measuring device according to claim 1, wherein the desired number of pulse time interval data to be averaged by the averaging circuit is the number of beats. 3. A musical tone tempo measuring device according to claim 1, which reproduces the displayed tempo meter as a metronome.