CN114155819A

CN114155819A - Method for detecting tone quality of violin resonator

Info

Publication number: CN114155819A
Application number: CN202111399155.3A
Authority: CN
Inventors: 陈旭
Original assignee: Acc Beijing Science And Technology Co ltd; AVIC Composite Corp Ltd
Current assignee: Acc Beijing Science And Technology Co ltd; AVIC Composite Corp Ltd
Priority date: 2021-11-23
Filing date: 2021-11-23
Publication date: 2022-03-08

Abstract

The present invention is a method for detecting the sound quality of a violin resonator. The method enables the violin resonator 1 to simulate sound by fixing the violin resonator 1 and setting the magnetostrictive audio transducer 9 on it for simulating the vibration of strings. Then the sound sensor 12 records the sounding data of the violin resonator, and obtains the characteristic spectrum of the violin resonator 1. By comparing the characteristic spectrum of the standard violin resonator and the violin resonator to be tested, the Multiple formant frequencies and sound pressure levels can determine the pronunciation effect of the violin resonator to be tested, and provide a basis for the improvement of the violin resonator in terms of material selection, thickness, and shape.

Description

Method for detecting tone quality of violin resonator

Technical Field

The invention discloses a method for detecting the tone quality of a violin resonator, and belongs to the technical field of measurement.

Background

As a musical instrument widely popular around the world, a violin resonator has been made of wood. Using a violin panel as an example: firstly, the fir wood with the growth period of hundreds of years is required to be used, the density and the uniformity of the annual rings of the wood are also required, and the water content of the wood is reduced by placing for 5 to 10 years. The annual domestic yield of violins which are selected from such harsh materials is about 150 thousands of violins, and the amount of wood consumed is conceivable. With the shortage of wood resources, people begin to find raw materials capable of replacing wood to manufacture a violin resonator.

The violin resonator made of a new material instead of the original wood has the following difficulties: firstly, screening materials: for a long time, the material of the violin resonator is wood, and people invest a great deal of research on how to select wood, such as the requirement on the water content of the wood, the requirement on the annual ring distance of the wood and the like, and after a material system is changed, the original experiences are not applicable any more, and how to establish a new material selection standard needs a great deal of tests to determine; secondly, evaluating the sound quality: the most important function of the violin is sounding, but how to judge the quality of the violin tone quality has no unified objective standard all the time, even a tone color description term system cannot be completely unified, how to objectively evaluate the tone quality of the violin without depending on subjective hearing is the second difficulty faced by people; thirdly, evaluation of resonator: the violin resonator plays a role in amplifying and modifying sound for the sound production of the violin, but the resonator is not the only factor influencing the final tone quality of the violin, and the factors such as the material of strings, the strength of a violator, the thickness of a bridge and the like can play a more or less role in the tone quality of the violin, so that the influence of other factors is eliminated, and the third difficulty is that the quality of the violin resonator is independently evaluated.

Disclosure of Invention

The invention provides a method for detecting the tone quality of a violin resonator aiming at the existing situation, and aims to realize the unified pronunciation evaluation of the violin resonators with different materials, thicknesses and shapes by detecting the tone quality of the violin resonator.

In order to achieve the above object, the technical solution of the present invention is as follows:

in the tone quality detection method of the violin resonator, the violin resonator 1 is fixed on a base 6, a bridge pressure support 10 is arranged at the bridge of the violin resonator 1 to install and fix a magnetostrictive audio transducer 9, the magnetostrictive audio transducer 9 is connected with a sweep frequency signal generator 11, a sound sensor 12 is placed above a violin f hole 3 of the violin resonator 1, the sound sensor 12 is connected with a computer 13 with recording and spectrum analysis functions, and the detection method comprises the following detection steps:

step one, selecting a violin with approved tone quality as a standard violin, fixing a resonance body of the standard violin according to the mode and configuring the assembly;

setting the initial frequency, cut-off frequency, voltage and running time of the frequency sweeping signal generator 11, starting running, and simultaneously recording by the computer 13 through the sound sensor 12;

thirdly, the recorded sound file is subjected to Fourier transform algorithm to obtain the characteristic frequency spectrum of the standard violin resonator_{Standard of merit}Sequentially marking the resonance peaks_{Standard of merit}；

Step four, repeating the step one to the step three, detecting the violin to be detected, and obtaining the characteristic frequency spectrum of the violin resonator to be detected_{To be measured}Sequentially marking the resonance peaks_{To be measured}；

And fifthly, comparing the characteristic frequency spectrums of the standard violin and the violin to be tested, and evaluating the sounding effect of the violin to be tested by comparing the frequency and sound pressure level difference of the standard formant and the formant to be tested.

In implementation, a tail post clamp 7 and a headstock clamp 8 are arranged on the base 6 to fix the rear end and the front end of the violin respectively.

In implementation, the tail pillar clamp 7 and the headstock clamp 8 are both clamp clamps with adjustable clamping force.

In implementation, the bridge pressure support 10 is used for tightly fixing the magnetostrictive audio transducer 9 from above, and the pressure is adjustable.

In practice, the acoustic sensor 12 is mounted 10 to 70mm above the violin f-hole 3 of the violin resonator 1.

In practice, recording software and spectrum analysis software are installed in the computer 13.

In practice, the frequency range of the sweep signal generator 11 is set to 20-20000 Hz. In practice, the running time of the sweep signal generator 11 is set to 2 seconds.

According to the technical scheme, the violin resonator 1 is fixed and the magnetostrictive audio transducer 9 for simulating string vibration is arranged on the violin resonator 1, so that the violin resonator 1 can simulate the stress state and the vibration state during sounding, sounding data of the violin resonator is recorded through the sound sensor 12, a characteristic frequency spectrum diagram of the violin resonator 1 is obtained, the sounding effect of the violin resonator to be tested can be determined by comparing a plurality of resonance peak frequencies and sound pressure levels in the characteristic frequency spectrum diagrams of a standard violin resonator and the violin resonator to be tested, and a basis is provided for improvement of the violin resonator in the aspects of material selection, thickness, shape and the like.

In the technical scheme of the invention, the combined action of the base 6 for fixing the violin resonator 1, the tail column clamp 7 and the headstock clamp 8 can simulate the bending stress of the violin resonator during sounding;

in the technical scheme of the invention, an audio signal generated by a sweep frequency signal generator 11 is converted into a vibration signal by a magnetostrictive audio transducer 9 and is used for simulating the vibration of a bridge acting on a violin resonator 1 when strings are pulled, and the magnetostrictive audio transducer 9 is fixed at the bridge position of the violin resonator 1 by a bridge pressure support 10 and is used for applying pressure on the surface of the violin resonator 1 and simulating the pressure of the bridge acting on the violin resonator 1.

Compared with the prior art, the technical scheme of the invention has the beneficial effects and advantages that:

the violin resonance body is an important part directly influencing the violin sound production effect, the violin strings vibrate after being rubbed by a fiddle bow, then the vibration is transmitted to the violin resonance body through a fiddle code, and the air vibration in the violin resonance body cavity produces resonance coupling sound production, so that the effects of increasing sound power, strengthening overtone and improving tone quality are achieved. Through the acoustic vibration of the test violin resonance body, can more directly more quick record the pronunciation effect of violin resonance body, and then improve in aspects such as the selected material of violin resonance body, thickness, shape. Compared with a method for judging the tone quality of the violin directly by subjectivity, the method not only gets rid of the dependence on the subjectively judged tone quality of a musician, but also can eliminate the influence of other accessories of the violin on the tone quality, thereby shortening the judging time and reducing the judging cost.

Drawings

FIG. 1 is a schematic structural diagram of a device for detecting a violin resonator in the technical scheme of the invention

FIG. 2 is a schematic diagram of the connection relationship between the simulation and pickup assembly according to the present invention

FIG. 3 is a schematic diagram of a frequency spectrum emitted from a frequency sweep signal generator according to the present invention

FIG. 4 is a schematic diagram of a characteristic spectrum diagram of a violin resonator in the technical scheme of the invention

Structure of sound quality detector for violin resonator

In the figure: 1. the violin comprises a violin resonator, 2, a violin head, 3, a violin f hole, 4, a violin bridge, 5, a violin tail column hole, 6, a base, 7, a tail column clamp, 8, a head clamp, 9, a magnetostrictive audio transducer, 10, a bridge pressure support, 11, a sweep frequency signal generator, 12, a sound sensor, 13 and a computer.

Detailed Description

The technical scheme of the invention is further detailed in the following by combining the drawings and the embodiment:

referring to the attached figure 1, the adjustable fixing device for fixing the violin resonator 1 comprises a base 6, a tail post clamp 7 and a headstock clamp 8, and the string vibration simulation device comprises a magnetostrictive audio transducer 9 and a bridge pressure support 10; the tail column clamp 7 is used for fixing a tail column hole 5 of a violin resonator 1, the headstock clamp 8 is used for fixing a violin headstock 2, and the magnetostrictive audio transducer 9 is fixed on a bridge pressure support 10 and connected with a violin bridge 4.

Referring to fig. 2, the magnetostrictive audio transducer 9 is electrically connected to the sweep frequency signal generator 11, the magnetostrictive audio transducer 9 converts an audio signal emitted by the sweep frequency signal generator 11 into vibration, the sound sensor 12 is fixed at a position 10-70mm above the violin f-hole 3 and used for collecting a sound signal emitted by the violin resonator 1, the sound sensor 12 is electrically connected to the computer 13, the sound sensor 12 transmits the sound signal to the computer 13 and stores the sound signal in recording software, and the spectrum analysis software processes a sound file in the recording software into a characteristic spectrogram.

The method for detecting and testing the tone quality of the violin resonator 1 comprises the following steps:

the first step is as follows: selecting a violin with better tone quality as a standard violin resonator, detaching the accessory of the standard violin resonator, fixing the standard violin resonator according to the above mode and configuring the assembly;

the second step is that: turning on the frequency sweep signal generator 11, setting the frequency range to be 20-20000Hz and the running time to be 2 seconds, and simultaneously turning on the recording software for recording;

the third step: importing the recorded sound file into spectrum analysis software, and obtaining the characteristic spectrum of the standard violin resonator through a fast Fourier transform algorithm_{Standard of merit}And successively labeling formants, F₀、F₁、F₂、F₃、F₄；

The fourth step: repeating the steps from one to three on the manufactured violin resonator to be detected, detecting the violin to be detected, and obtaining the characteristic frequency spectrum of the violin resonator to be detected_{To be measured}And successively labeling formants, F₀ ^’、F₁ ^’、

”’

F₂、F₃、F₄；

The fifth step: and sequentially comparing the frequency and the sound pressure level difference of each resonance peak, and evaluating the sounding effect of the violin resonance body to be tested.

Claims

1. A sound quality detection method for a violin resonator, wherein the violin resonator (1) is fixed on a base (6), and a bridge pressure bracket (10) is set at the bridge of the violin resonator (1). ) to install and fix a magnetostrictive audio transducer (9), the magnetostrictive audio transducer (9) is connected with the frequency sweep signal generator (11), and the sound sensor (12) is placed on the violin resonator (1). ) above the violin f hole (3), the sound sensor (12) is connected with a computer (13) with recording and spectrum analysis functions, and the detection steps of the detection method are as follows:

Step 1. Select a violin whose sound quality is recognized as a standard violin, fix the resonance body of the standard violin and configure the components according to the above method;

Step 2, setting the starting frequency, cut-off frequency, voltage, and running time of the frequency sweep signal generator (11), starting the operation, and simultaneously, the computer (13) performs recording through the sound sensor (12);

Step 3: Pass the recorded sound file through the Fourier transform algorithm to obtain the characteristic spectrum _standard of the standard violin resonator, and mark the formant _standard in turn;

Step 4. Repeat steps 1 to 3 to detect the violin to be tested, obtain the characteristic spectrum of the resonance body of the violin to be tested to be tested, and mark the formants _{to be} _tested in turn;

Step 5: Compare the characteristic spectrum of the standard violin and the violin to be tested under the same vibration mode, and evaluate the pronunciation effect of the violin to be tested by comparing the frequency and sound pressure level difference between the standard formant and the formant to be tested.

2. the sound quality detection method of violin resonance body according to claim 1, is characterized in that: be provided with tail post clamp (7), headstock clamp (8) on the base (6) to fix the rear end and the front end of the violin respectively .

3. The method for detecting the sound quality of a violin resonator according to claim 2, wherein the tail post clamp (7) and the headstock clamp (8) are clamps with adjustable clamping force.

4. The method for detecting sound quality of a violin resonator according to claim 1, wherein the saddle pressure bracket (10) presses and fixes the magnetostrictive audio transducer (9) from above, and the pressure Adjustable.

5. The method for detecting sound quality of a violin resonator according to claim 1, wherein the installation position of the sound sensor (12) is 10-70 mm above the violin f-hole (3) of the violin resonator (1).

6 . The method for detecting the sound quality of a violin resonator according to claim 1 , wherein the computer ( 13 ) is equipped with recording software and spectrum analysis software. 7 .

7. The method for detecting sound quality of a violin resonator according to claim 1, wherein the frequency range of the set frequency sweep signal generator (11) is 20-20000 Hz.

8. The method for detecting sound quality of a violin resonator according to claim 1, wherein the set running time of the frequency sweep signal generator (11) is 0.1-10 seconds.