JP2006010869A - Device and method for tuning - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a tuning device capable of extracting a timbre as well as a musical interval. <P>SOLUTION: The tuning device comprises an input means 1 for inputting a sound and a musical sound signal of a musical instrument to be tuned, a converting means 3 for extracting data of a frequency component from waveform data of the output signal of the input means, a waveform information storage part 2E which stores data of musical sound for a plurality of kinds, a musical sound retrieval part 2G which compares the data of the frequency component of the converting means with the data of waveforms in the waveform information storage part to retrieve data of an arbitrary musical sound waveform, and a control means 2F for receiving a signal of the musical sound retrieval part to judge tuning of the signal of the input signal. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a tuning device that measures a deviation between a fundamental frequency of a sound of a musical instrument or a musical sound signal and a reference frequency that is a reference for comparison, and displays the deviation.

  The conventional tuning device has a waveform shaping unit that converts a musical sound signal collected via an input means such as a microphone into a rectangular wave, and counts the edges between the rectangular waves output from the waveform shaping unit to thereby calculate the period. The calculation means for calculating and calculating the pitch from the period, the pitch name / octave discrimination means for discriminating the pitch name / octave of the obtained pitch, and the pitch error obtained with respect to the determined pitch name / octave reference pitch The display includes a pitch error calculation unit for calculation, and the display unit displays a pitch name, an octave, and a pitch error value (see, for example, Patent Document 1).

Further, as a tuning device for tuning a stringed instrument, the pitch of the input signal of the string played is detected, and the number of the string is displayed in correspondence with the detected pitch (see, for example, Patent Document 2).
JP 2000-66667 A JP-A-6-308946

Since the conventional tuning device is only a method of calculating the pitch by converting the input musical sound signal into a rectangular wave and counting the period of the rectangular wave, it relates to the pitch of the input musical sound as shown in FIG. Only display (note name, octave and cent error). For this reason, it is difficult to determine the difference in tone color. For example, in the case of a piano where the pitch name E of octave 2 is the same as the pitch name E of the open string of the guitar 6 string, as shown in FIG. In addition, the display related to the pitch (sound name and cent error) is the same, and it is difficult to display the instrument to be tuned or the display of the difference in tone.
Further, when tuning a stringed instrument, the tuner must understand the correspondence between the string number and the pitch name, and there is a problem that it is difficult for a beginner to tune a string. For example, when exchanging strings of stringed instruments, as a problem when using a tuning device that displays the string name or a tuning device that displays the pitch name and octave, the pitch played by the string to be tuned is the target Since string names and pitch names other than strings are displayed, it is often the case that the tuning decision is high or low with respect to the target pitch. In the process of tuning a string with a high pitch of a stringed instrument, a string with a low pitch is often displayed, and in order to improve the effect, the tuner has to specify the string to tune itself. It was. It was difficult to judge the difference in timbre.

The tuning device of the present invention has input means for inputting the sound of a musical instrument to be tuned or a musical sound signal, and conversion means for converting the input signal into a time-series signal for each of a plurality of frequency bands, and information on the waveform of the musical sound By having a stored waveform information storage unit and a musical tone search unit for searching for waveform information corresponding to the musical tone signal input from the waveform information storage unit, various tuning operations relating to the musical sound waveform to be tuned can be performed. It is something to be affected. As an example, it is possible to automatically determine the pitch name that is the target of tuning and display only the pitch name that is the target of tuning, thereby reducing misrecognition by the tuner.
In addition to the display of the pitch such as the pitch name, the timbre can be tuned easily, quickly and surely by displaying timbre information.

  The present invention relates to a pitch extraction unit that extracts a period from a musical tone signal of a musical instrument sound, a period detected by the extraction unit and reference period data stored in a memory, and a chromatic pitch name of the detected period A search unit that searches for an octave, a cent value calculation unit that calculates a cent value of the detected pitch with the reference pitch, a tone waveform reference spectrum stored in a waveform information storage unit, and a spectrum of the tone signal. In comparison, the tuning device has a musical tone search unit for searching for musical tone information, musical tone information output from the musical tone search unit, the pitch name, and a display unit for displaying the cent value.

Furthermore, the musical tone information is data indicating the type of musical instrument.
Further, the music information is data having the string number of the stringed instrument. Further, the music information is data having the number of frets of the stringed instrument.

  The present invention extracts the period of the musical sound, searches for the chromatic pitch name and octave of the period, calculates the deviation from the reference pitch of the period, and compares the musical sound spectrum with the reference spectrum to determine the type of musical instrument. Judgment was made, and the musical instrument tuning method was displayed to display the note name, octave, deviation, and instrument type.

  The tuning device of the present invention recognizes the waveform of a musical tone to be tuned, automatically determines a pitch name that is the target of tuning, and reduces malfunctions of tuning. For example, when tuning a stringed instrument, even if you do not know the correspondence between the string number and the pitch name to be tuned, only the target string number or pitch name is displayed. This has the effect of reducing malfunctions such as avoiding display.

  In addition to the display of the pitch such as the pitch name, the timbre information about the musical tone is displayed, so that even a beginner can easily, quickly and surely perform tuning.

  An embodiment of a tuning device according to the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a block diagram showing the configuration of a tuning device to which the present invention is applied. The overall operation of the tuning device is controlled by a microcomputer 2. The microcomputer 2D includes a read-only memory storing a program for controlling the operation of the entire tuning device, a random access memory as a working area necessary for executing the program, and the like. There is.

  The input means 1 is composed of a microphone that converts the sound of the musical instrument into an electric signal, a low-frequency amplifier that amplifies the electric signal obtained via the jack, and the like. Output to the shaping means 4.

  The conversion means 3 is a Fast Fourier Transform (FFT) described later, and outputs an FFT analysis signal (data based on the frequency spectrum as shown in FIG. 2) to the MCU (microcomputer) 2. . The waveform shaping unit 4 receives the output signal from the input unit 1 and outputs the waveform-shaped electric signal S2 (rectangular wave) to the MCU2.

A pitch extraction unit 2A, a pitch name / octave search unit 2B, a cent value calculation unit 2C, a memory 2D, a waveform information storage unit 2E, a musical sound search unit 2G, and a control unit 2F, which are pitch extraction means, You may be comprised with a computer.
The setting unit 6 includes a circuit that generates a switch signal by opening and closing the switch member, and performs an operation for selecting an instrument to be tuned, a string of a stringed instrument, or a chromatic pitch name from the outside. The signal of the setting unit 6 is output to the control means 2F inside the MCU (microcomputer) 2.

  The waveform information storage unit 2E stores information on frequency spectra of waveforms for pitches, octaves, and strings of guitars, for example, as shown in the table of FIG. 2 for a plurality of types of frequency bands.

  The musical sound search unit 2G compares the frequency spectrum signal after FFT analysis output from the conversion means 3 with the frequency spectrum signal stored in advance in the waveform information storage unit 2E. For example, the type of guitar string It is also possible to search for musical tone information related to the above and output it to the control means 2F. Moreover, you may output to the control means 2F in order to display the frequency spectrum signal of FFT analysis.

  The pitch extraction unit 2A measures the time interval for each rising or falling of the rectangular wave shown in the electric signal S2, and extracts the pitch (period) of the electric signal S2, that is, the musical sound signal S1. The extracted pitch signal is output to the pitch name / octave search unit 2B.

  The pitch name / octave search unit 2B stores the reference period data of the octave (full 8 degree pitch) and pitch names (names given to 12 different sounds included in the octave) stored in the memory 2D. The pitch and the extracted pitch signal, and the chromatic (full 8 degree pitch, ie, one octave divided into 12 semitones) pitch names from the reference period data close to the extracted pitch Is calculated. The search unit 2B outputs the calculated chromatic signal to the cent value calculation unit 2C and the control unit 2F, and outputs the pitch signal to the cent value calculation unit 2C.

  The cent value calculation unit 2C receives the chromatic semitone signal searched from the pitch name / octave search unit 2B and receives one cent of each chromatic semitone stored in the memory 2D (the cent is a chromatic semitone). The reference data corresponding to one cent of the corresponding semitone is read out from the reference data corresponding to a pitch of about 1/100). The cent value calculation unit 2C calculates a cent value for the chromatic semitone based on the reference data of 1 cent of the corresponding semitone and the extracted pitch signal, and outputs the cent value to the control means 2F.

  The control means 2F receives output signals from the pitch name / octave search unit 2B, the cent value calculation unit 2C, and the musical tone search unit 2G, and adds octave, pitch name and cent value, and musical tone information acquired by FFT, A signal intended to display the form tuning information is output to the display unit 3. In addition, the control means 2F receives a signal from the musical tone search unit 2G, controls the data of the pitch name / octave search unit 2B and the cent value calculation unit 2C, and prevents, for example, a stringed instrument from being displayed. When tuning, it is possible to realize an operation of displaying only the target string number or pitch name without knowing the correspondence between the string number and pitch name to be tuned.

  The display unit 3 includes a needle meter, a liquid crystal display element, and an LED element, and can display various forms of tuning information.

  The tuning device having the above-described configuration can be carried using a portable battery such as a battery as a power source.

  An example of the conversion means 3 is a fast Fourier transform, which includes an A / D converter 3A and a fast Fourier transform unit 3B. The A / D converter 3A is a circuit that converts an analog signal into a digital signal. For example, sampling may be performed at a sampling frequency of 44.1 kHz, and digital data converted into 16-bit quantization may be captured. Since it increases, the sampling frequency and quantization may be set to a low value according to the musical instrument to be referred to. (If it is a guitar, it is good also as a sampling frequency of 11 kHz.) The fast Fourier transform part 3B is a method of analyzing the time series signal (spectrogram) for every frequency band in a short time, and in the case of the sampling frequency of 11 kHz, it is from 0 Hz. Frequency spectrum information up to 5.5 kHz can be obtained. As means for realizing the fast Fourier transform unit 3B, FFT analysis by a digital signal processing unit including a DSP (digital signal processing unit), various buffers, registers, and DMA (DIRECT MEMORY ACCESS) is desirable.

  FIG. 2 is a numerical example of the frequency spectrogram after the FFT processing, and is stored in the waveform information storage unit 2E. The numerical value A in the leftmost vertical axis direction is an address. From the numerical value B (00000000), the chromatic octave, pitch name, guitar open string sample example, guitar 12 fret (12F) harmonics sample example, and frequency 63Hz , 128 Hz, 256 Hz, 512 Hz, 1024 Hz, 2048 Hz. As described above, the waveform information storage unit 2E stores the frequency spectrum data of various musical sounds, and may be a rewritable memory. (It may be frequency spectrum data in various forms such as instrument type, string, tuning style, etc.) The address value (00000100) is an example of a spectrogram of a 6-string open string, and a chromatic note name notation (octave) 2) Note name E).

  FIG. 3 is a graph showing the levels of the six open strings, and is a display example of the tuning device of the present invention when a frequency spectrogram as a tone color of a musical sound waveform is added from the display unit 5. The cent value display section 11 displays the difference from the reference frequency as a cent value from -50 to +50, the pitch name display section 12 shows the keyboard and the pitch name 13 on the keyboard, and the measured pitch name E Lights up. The octave corresponding to the frequency is shown in the octave display unit 15, and the two-octave display of the measured value is lit among the lamps 16 corresponding to each octave.

  The tone display section 20 displays guitar, string number 6, open fret string, octave 2, tone E, and cent value 0 as musical tone types. The spectrum display unit 30 displays the level indicating the intensity of sound on the vertical axis at a frequency of 6 steps from 64 Hz to 2048 Hz.

  FIG. 4 is an example showing the frequency level when the musical sound of octave 2 / note name E is represented by a string with different strings of the guitar string number (for example, when a string of a stringed instrument is replaced, the string is wound up) In the process, there is a process in which the pitches are the same even for strings with different string numbers.) FIG. 5 is a graph showing the frequency level of FIG.

  In the graph of FIG. 5, for example, in the process of winding a string when exchanging the strings of a guitar, the pitch may be the same even if the string has a different string number, and even if the pitch name of the chromatic is the same, It is possible to extract the characteristics of the musical sound due to the difference in frequency spectrum. By using the frequency spectrum, it is possible to display the instrument to be tuned and various displays that show differences in timbre, and when tuning a stringed instrument, the tuner understands the correspondence between the string number and the pitch name. By displaying only the tuning information of the target string at least, it is possible to easily and surely tune by avoiding the display of pitches with different string numbers.

  In actual operation, the conversion means 3 outputs a spectrogram signal as shown in FIG. 2 to the control means 2F via the musical tone search unit 2G. In this way, the control means 2F receives the signal from the conversion means 3 and prevents the malfunction of pitch extraction from the control means 2F, and displays the waveform tone color from the display unit 5, for example, the spectrogram waveform as shown in FIG. It doesn't matter.

  A series of these operations will be described step by step with reference to the flowcharts of FIGS.

  FIG. 6 is a main routine of the tuning device of the present invention. Step S100 in FIG. 6 is a routine that is executed when the tuning device is activated, and is a routine that initializes various buffers, registers, parameters, and the like. The MPU 2, that is, the microcomputer that controls the tuning device as a whole is executed. It is initialized. When step S100 ends, the process proceeds to step S101.

Step S101 is a routine for setting a tuning mode intended by the tuner from the outside and capturing the state. Setting for selecting an instrument to be tuned, a string of a stringed instrument, or a chromatic note name from the outside. Then, it progresses to step S102.
In step S102, the output signal (electric signal S2) of the waveform shaping 4 is captured, and the process proceeds to step S103.

  Step S103 is a routine for performing pitch extraction, and extracts the electrical signal S2, that is, the pitch (cycle) of the musical sound signal S1, by counting the time interval at each rising or falling of the rectangular wave shown in the electrical signal S2. The process proceeds to step S104.

  In step S104, the reference period data of the octave (complete pitch of 8 degrees) and pitch names (names given to 12 different sounds included in the octave) stored in the memory 2D and the extracted pitch are stored. And the pitch name and octave of the chromatic (complete 8 degree pitch, that is, the name obtained by dividing one octave into 12 semitones) are calculated from the reference period data close to the extracted pitch. The process proceeds to step S105.

  Step S105 receives the signal of the searched chromatic semitone and corresponds to one cent of each chromatic semitone stored in the memory 2D (cent is a pitch about one hundredth of the chromatic semitone). The reference data of one cent of the corresponding semitone is read from the reference data. The cent value calculation unit 2C calculates the cent value for the chromatic semitone based on the reference data of one cent of the corresponding semitone and the extracted pitch signal, and the process proceeds to step S106.

  Step S106 receives the spectrum data calculated by the fast Fourier transform unit 3B (FFT: Fast Fourier Transform), compares the spectrum data with the reference spectrum data of the musical sound waveform stored in the waveform information storage unit 2E, and the estimated instrument Musical tone information such as timbre is acquired, and the process proceeds to step S107.

  Step S107 is a display routine that is displayed based on the settings captured in step S101 from various forms of tuning information, such as the octave of the input musical tone, the pitch name and cent value, and the musical tone information acquired by FFT. The unit 5 performs an operation for displaying the tuning state. After the execution of step S107, the main routine is returned.

  FIG. 7 shows the steps of the fast Fourier transform executed by the transforming means 3. Step S300 in FIG. 7 is a routine that is executed when the tuning device is activated, and initializes various buffers, registers, parameters, and the like of the digital signal processing unit made up of the DSP as an example of a component of the conversion unit 3. It is a routine. When step S300 ends, the process proceeds to step S301.

  Step S301 is a routine for acquiring waveform information, and aims to sample the waveform by converting the input musical sound into digital data, and stores the acquired data in a DMA (DIRECT MEMORY ACCESS) or the like. When step S301 ends, the process proceeds to step S302.

  Step S302 is a step of extracting frequency components by fast Fourier transform, and quantification (level data) of each frequency component is calculated from the musical sound waveform sampling data acquired in step S301. As an example of quantification of frequency components, data as shown in FIG. 2 is listed, and desired finite-length spectrum information is calculated by calculation of digital signal processing. When the process of step S302 ends, the process proceeds to step S303.

  In step S303, after the calculated spectrum information is output to the MCU (microcomputer) 2, the waveform is sequentially acquired, and the process returns to repeat the above series of actions.

  Thus, the waveform information storage unit 2E constituted by the MCU (microcomputer) 2, the control unit 2F, the pitch extraction unit 2A described above, the search unit 2B, the cent value calculation unit 2C, and the memory The operation with 2D can be realized by the program described above. Moreover, the conversion means 3 which implements a fast Fourier transform process comprised by A / D converter, DSP, etc. is realizable with a program.

It is a block diagram which shows the structure of the tuning apparatus which shows the Example of this invention. It is a numerical example of the frequency spectrogram after FFT processing. It is an example of a display of the tuning apparatus of this invention. It is an example which shows the frequency level of the string of a guitar. FIG. 5 is a graph showing the frequency level of FIG. 4. It is a flowchart of the main routine of the tuning apparatus of this invention. 4 is a flowchart executed by conversion means 3; It is an example of a display of the conventional tuning apparatus.

Explanation of symbols

1 Input means 2 MCU (microcomputer)
3 Conversion means 4 Waveform shaping means 5 Display section 6 Setting section 3A A / D converter (analog / digital conversion section)
3B Fast Fourier transform unit 2A Pitch extraction unit 2B Pitch name / octave search unit 2C Cent value calculation unit 2D Memory 2E Waveform information storage unit 2F Control means 2G Music search unit S1 Music signal S2 Electric signal

Claims (18)

In a tuning device that has a display unit that measures the deviation between the fundamental frequency of the sound of a musical instrument to be tuned and a reference frequency that is a reference for comparison and the reference frequency,
Input means for inputting the sound of the musical instrument and the musical sound signal;
A tuning apparatus comprising conversion means for extracting frequency component data from waveform data of an output signal of the input means. In a tuning device equipped with a display that measures the deviation between the fundamental frequency of the instrument to be tuned and the fundamental frequency of the musical tone signal and the reference frequency that is the reference for comparison, and displays the deviation.
Input means for inputting the sound of the musical instrument and the musical sound signal;
Conversion means for extracting frequency component data from the waveform data of the output signal of the input means;
A waveform information storage unit storing musical sound data for a plurality of types;
A tuning device comprising: a musical tone search unit that compares the frequency component data with the waveform data stored in the waveform information storage unit and searches for similar musical sound waveform data. In a tuning device equipped with a display that measures the deviation between the fundamental frequency of the instrument to be tuned and the fundamental frequency of the musical tone signal and the reference frequency that is the reference for comparison, and displays the deviation.
Input means for inputting musical instrument sounds and musical sound signals;
Conversion means for extracting frequency component data from the waveform data of the output signal of the input means;
A waveform information storage unit storing musical sound data for a plurality of types;
A musical sound search unit that compares the data of the frequency component of the conversion means and the waveform data of the waveform information storage unit, and searches for similar musical sound waveform data;
A tuning device comprising control means for judging the tuning of the signal of the input means from the signal of the musical tone search section.   The tuning device according to claim 1, wherein frequency component data is displayed on the display unit.   2. A tuning apparatus according to claim 1, wherein said converting means comprises a fast Fourier transform.   The tuning apparatus according to claim 2, wherein the waveform information storage unit stores at least two types as information of the waveform. In a tuning device equipped with a display that measures the deviation between the fundamental frequency of the sound of a musical instrument or a musical sound signal and a reference frequency that serves as a reference for comparison, and displays the deviation.
A setting unit for receiving signals from the outside;
Input means for inputting the sound of a musical instrument to be tuned and a musical tone signal;
A tuning apparatus comprising conversion means for extracting frequency component data from waveform data of an output signal of the input means. A tuning method for displaying a deviation between a fundamental frequency such as a sound of a musical instrument or a musical sound signal and a reference frequency as a reference for comparison,
Initializing when the tuning device is activated; and
Receiving the sound of the instrument and the tone signal and extracting the pitch;
Searching for tuning information from the extracted pitch;
Obtaining frequency data from the conversion means;
Comparing the frequency data and the waveform information storage unit data to obtain tuning information;
And a display step of displaying the tuning information from the display unit. A tuning method for displaying a deviation between a fundamental frequency such as a sound of a musical instrument or a musical sound signal and a reference frequency as a reference for comparison,
Initializing when the tuning device is activated; and
Receiving the sound of the instrument and the musical sound signal and obtaining waveform data;
Extracting the frequency data from the waveform data.   4. A tuning apparatus according to claim 3, wherein said control means comprises a microcomputer.   The tuning device according to claim 1, wherein the display unit is configured by a liquid crystal display element.   The tuning device according to claim 1, wherein the display unit includes an LED element.   2. The tuning device according to claim 1, wherein the tuning device uses a portable battery as a power source. A pitch extractor for extracting the period from the musical tone signal of the musical instrument;
A search unit that compares the period detected by the extraction unit with reference period data stored in a memory, and searches for a chromatic pitch name and an octave of the detected period;
A cent value calculation unit for calculating a cent value with the reference pitch of the detected period;
A musical sound search unit that searches for musical tone information by comparing a spectrum of a musical sound waveform reference stored in a waveform information storage unit with a spectrum of the musical sound signal;
A tuning apparatus having a display unit for displaying musical tone information output from the musical tone search unit, the pitch name, and the cent value.   The tuning apparatus according to claim 14, wherein the musical tone information includes data indicating a type of musical instrument.   The tuning device according to claim 14 or 15, wherein the music information includes a string number of a stringed instrument.   The tuning apparatus according to claim 16, wherein the music information includes the number of frets of a stringed instrument.   The period of the musical sound is extracted, the chromatic note name and octave of the period are searched, the deviation from the reference pitch of the period is calculated, and the musical instrument type is determined by comparing the spectrum of the musical sound with the reference spectrum. A musical instrument tuning method for determining and displaying the note name, the octave, the deviation, and the type of the musical instrument.

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