JPS63178299A - Guitar - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a guitar, and more particularly to a vibration detector for an electric guitar or an electronic guitar.

[Prior Art] Conventionally, this type of electric guitar was developed by Japanese Patent Application Laid-Open No. 59-140.
The one disclosed in Japanese Patent No. 497 is known. The string vibration detection sensor disclosed in Japanese Patent Application Laid-Open No. 59-140497 has a plurality of strings 23.
24, 25, 26, 27, and 28, and when the string vibrates, the change in the amount of light caused by the shadow of the string is converted into a change in voltage by the converter 38. Therefore, the vibration of the string is transmitted to the transducer 3
It is detected based on the change in the output voltage of 8.

[Problems to be Solved by the Invention] According to the principle explained in FIGS. 3 to 10 of JP-A No. 59-140497, the conventional string vibration detection sensor described above has a plurality of sensors on the optical path. Even if the strings are positioned differently, if the strings are in different positions, it is possible to detect the presence or absence of vibration occurring in any one of the plurality of strings. However, when multiple strings are plucked at the same time, a single converter 38 detects changes in the amount of light based on the vibrations of the multiple strings, so vibrations generated in each of the multiple strings are detected. The problem was that it was not possible to detect each frequency separately.

Even if an attempt is made to provide an incandescent lamp 30, a converging lens 36, and a converter 38 for each string in order to solve this problem, the distance between adjacent strings is extremely narrow, so the incandescent lamp 30, converging lens 36, and transducer 38 are installed at each interval. It is impossible to provide these, and if one were to attempt to provide them, the spacing between the strings would become extremely wide, creating a form that would be unsuitable for practical use as an electric guitar.

Therefore, an object of the present invention is to provide a guitar equipped with an optical vibration detector that can be placed even in a narrow space.

[Means for Solving the Problems] The present invention was made based on the fact that if the optical path is extremely narrow, a sufficient amount of light can be obtained even with a light emitting element. In the guitar, the guitar is equipped with a plurality of strings, and a conversion circuit that converts and outputs vibrations generated in the strings when the strings are plucked into electrical signals having a waveform corresponding to the waveform of the vibrations, wherein the conversion circuit corresponds to each of the strings. The string has a vibration detector composed of a plurality of photocouplers provided respectively in the strings, and each string is positioned on the optical path of the corresponding photocoupler when not vibrating.

[Operation and Effect] When multiple strings of the guitar according to the above configuration are plucked at the same time,
Each string vibrates at a frequency corresponding to the frets it touches. Each string has a corresponding photo when not vibrating.

It is located on the optical path of the Cobra, but when the string vibrates, the string crosses the optical path, and the light emitted from the photocoupler's light emitting element is reflected and scattered by the string every time the string crosses the optical path. As a result, the photocoupler's light-receiving element outputs an electrical signal with a frequency corresponding to the frequency of the string. Then, a musical tone having a pitch corresponding to the vibration frequency of each string can be reproduced based on the electric signal supplied from the light receiving element corresponding to each string by the sound generating means provided inside or outside the guitar.

In this way, the frequency of vibration generated in each string is detected by a photocoupler installed corresponding to each string, so even when multiple strings are plucked at the same time, the frequency of vibration generated in each string is detected. Musical tones can be generated simultaneously. Moreover, since the photocoupler can be installed in an extremely small space, an optical vibration detector can be attached to the electric guitar currently in use without changing the string spacing.

Generally, optical vibration detectors are inherently more resistant to noise than electromagnetic vibration detectors, and are easier to control independently for each string. Furthermore, since the optical vibration detector detects the vibration waveform of the string more accurately than the piezoelectric detector, it can generate musical tones with better sound quality than the piezoelectric detector.

Therefore, by optically detecting the frequency of each string without changing the string spacing of a conventional guitar,
A guitar that is resistant to noise and has good sound quality can now be put into practical use.

[Example code] Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a front view showing a first embodiment of the present invention. In the first embodiment, the present invention is applied to an electric guitar.

In FIG. 1, 1 is a guitar body consisting of a body 3 and a neck 5, and a plurality of string windings 9 provided at the tip of the neck 5.
Six strings 13 having different thicknesses are stretched between the strings 11 and the tail bead 11 provided on the body 3. A bridge 15 and an optical vibration detector 17 are sequentially arranged on the body 3 from the tail bead 11 side.
Inside, two transmission photocouplers 19,21 are provided for each string 13, as shown in detail in FIG. The first photocoupler 19 is arranged so that its optical path extends substantially perpendicular to the surface of the body 30, and the second photocoupler 21 is arranged so that its optical path extends substantially parallel to the surface of the body 3. It is located. The string 13 is located on both optical paths when not vibrating. The optical path emanating from each photocoupler 19.21 has a diameter approximately equal to the diameter of each string, and the vibration detector 17 obtained by assembling these photocouplers 19.21 is placed in the vicinity of the bridge 15. Therefore, even if the string 13 vibrates slightly, each photocoupler 19.
The voltage generated by the light receiving element 21 changes, and
does not go out of the detectable range of the photocouplers 19 and 21.

Generally, the plucked string 13 has vibrations in a direction approximately parallel to the surface of the body 3 (hereinafter referred to as the X direction) and vibration in a direction approximately perpendicular to the surface of the body 3 (hereinafter referred to as the Y direction). A synthesized vibration is generated. However, although the vibration immediately after a string is plucked contains many Y-direction vibration components, as time passes, the X-direction vibration component increases. Therefore, as in this embodiment, two photocouplers 19 having different angles of about 90 degrees are used.
．． If the vibrations generated in each string 13 are detected in step 21, the amplitude of the vibrations can be accurately detected over the entire period from the generation of the vibrations to the end of the vibrations. Also, photocoupler 1
9.21 may be one that generates and detects visible light, but
The light emitting element may be an infrared light emitting diode, and a visible light filter may be attached to the light receiving element side. In this way, the influence of natural light can be eliminated and highly accurate detection can be performed.

The output signals of photocouplers 19, 21 provided corresponding to each string are amplified by amplifiers 23, 25, etc. provided inside or outside the guitar as shown in Figure 3, and then sent to a mixer circuit. Mixed at 27. Thereafter, the signal is sent to the speaker system 31 and used to generate musical tones.

FIG. 4 is a front view of a photocoupler used in the second embodiment of the present invention, and the second embodiment has the same configuration as the first embodiment except that a reflective photocoupler 41 is used. . The reflective photocoupler 41 irradiates light onto the string 13 and converts the reflected light into an electrical signal on the light receiving element side. Therefore, in the second embodiment, the side of the string 130 opposite to the body can be kept open.

FIG. 5 is a block circuit diagram of a third embodiment of the present invention.

The third embodiment is an application of the present invention to an electronic guitar, in which a musical tone generation circuit of an electronic sound source is controlled based on detected string vibration information (electrical signal). This embodiment has the same configuration as the first embodiment except for the electronic circuit, so only the electronic circuit will be explained and the explanation of the other configurations will be omitted.

As shown in Figure 5, when plucking the string, the photocoupler 19
．． The voltage of the output signal generated by the light receiving element 21 is determined by the comparator 5.
1.53 and are compared with reference voltages Vthl and Vth2, respectively. The reference voltage vth1 is set to a low voltage value, and the comparator 51 outputs a high level signal over substantially the entire vibration period of the string 19.21. When the comparator 51 outputs a high-level signal, the one-shot pulse generation circuit 55 detects the rising edge of the output signal of the comparator 51 and outputs a high-level signal to the counter 5.
A pulse is supplied to the reset terminal of the timer 7 and the reset terminal of the timer 59. As a result, the counter 57 and timer 59 are reset to prepare for the counting operation described below.

On the other hand, since the reference voltage Vth2 of the comparator 53 is set to a high voltage level, the comparator 53 detects the peak of string vibration and supplies the gate circuit 61 with a number of pulses corresponding to the number of peaks. Since the gate circuit 61 is turned on by the timer 59 which starts timing immediately after the above-mentioned reset, the output pulse of the comparator 53 is supplied to the counter 57 and the output pulse from the comparator 53 is output from the gate circuit during a preset time. The number of output pulses of the comparator supplied via 61 is counted.

Since the number of output pulses supplied from the comparator 53 during a certain period of time corresponds to the frequency of vibration of the string and the pitch of the musical tone desired by the performer, the code conversion circuit 63 uses the counter. The pitch of the musical tone to be generated is specified to the musical tone generating circuit 65 based on the count value left in the musical tone generating circuit 57, and the sound system 67 generates a musical tone based on the musical tone signal generated by the musical tone generating circuit 65.

[Brief explanation of the drawing]

FIG. 1 is a front view showing the configuration of the first embodiment of the present invention, FIG. 2 is a perspective view showing the configuration of the vibration detector of the first embodiment, and FIG. 3 is an electric circuit of the first embodiment. A block circuit diagram. FIG. 4 is a front view of a photocoupler used in a vibration detector according to a second embodiment of the present invention. FIG. 5 is a block circuit diagram showing an electronic circuit according to a third embodiment. l...Guitar body, 13...Strings, 17...Vibration detector, 19.21.41...Photocoupler. Patent applicant: Agent of Nippon Musical Instruments Co., Ltd.
Patent Attorney Kiyoshi Kuwai - Akira V] Illusion diagram of the travel device Figure 4 Front view of other photocouplers Figure 3 Block circuit diagram of the first embodiment

Claims (2)

[Claims] (1) A guitar equipped with a plurality of strings stretched over the guitar body, and a conversion circuit that converts and outputs the vibrations generated in the strings when the strings are plucked into an electrical signal with a waveform corresponding to the waveform of the vibrations, The conversion circuit has a vibration detector constituted by a plurality of photocouplers respectively provided corresponding to each of the strings,
A guitar characterized in that each string is positioned on the optical path of a corresponding photocoupler when not vibrating. (2) A plurality of the photocouplers are provided for each of the plurality of strings, and the plurality of photocouplers are provided at mutually different positions with respect to the strings.
Guitar listed in section.