RU2640169C2 - Plucked musical instrument - acoustic guitar - Google Patents

Abstract

FIELD: physics.SUBSTANCE: guitar consists of a neck with an upper nut and frets installed on it, a neck head with pins located thereon, strings, a body consisting of a shell, an upper, and a lower deck. The lower nut is installed separately on the outer surface of the deck.EFFECT: reduction in the energy losses of string vibrations transmitted to the upper deck, an increase in the amount of energy of the strings converted into sound waves, thereby improving all the acoustic characteristics of the guitar.7 cl, 6 dwg

Description

The invention relates to the field of plucked musical instruments, namely to the construction of guitars.

An acoustic guitar is known, consisting of a neck with a top nut and frets installed on it, a head of the neck with pegs located on it, a body consisting of a shell, an upper and lower deck, a string holder with strings fixed on it, resting on the lower threshold and transmitting vibrations of strings of the upper deck when playing (see O. Pukhol. School of playing the six-string guitar. Moscow, All-Union Publishing House "Soviet Composer", 1983).

The main purpose of any musical instrument, including guitar, is its ability to reproduce sound waves with specified acoustic characteristics, such as dynamic range (volume), attack speed, timbre. The most important characteristic of the guitar as a complex oscillatory system is the quality factor. The problem of creating instruments with the best acoustic characteristics has attracted the attention of the best masters around the world for centuries. She has not lost its relevance today. The disadvantages of the known designs include:

- low volume of sounding instruments. According to some estimates, it makes up 5-8% of the vibrational energy of strings. Many famous musicians and composers complained about the not-so-loud sound of a classical guitar;

- most tools have reasonable claims to such characteristics as attack speed, uneven frequency response, low quality factor of the oscillatory system.

The operational drawbacks of the existing design include a fairly common problem: partial or complete separation of the stand, due to the tension force of the strings.

My scientific research on the characteristics of acoustic guitars using the methods described in my RF Patent No. 2416128 of 04/10/2011, “Method for tuning and measuring the dynamic characteristics of stringed musical instruments and a device for its implementation”, showed: these shortcomings are largely due to the design stand holder, placed in the center of a large oval of the upper deck. The inventor of the stand is considered Dionisio Aguado (04/08/1784 - 12/20/1849) - Spanish virtuoso guitarist, composer, teacher. For more than 170 years, the Aguado stand has not undergone significant changes and consists of a base having a significant area (for a classical guitar more than 10% of the effectively radiated surface of a large oval of the upper deck) formed by a wire holder and a lower nut resting on the base.

The coasters of master guitars are usually made of rosewood and their average weight is about 35 grams or more, which often exceeds 30-40% of the most effectively oscillating mass of the upper deck, located in the central part of a large oval, mainly forming the main acoustic characteristics of the instrument. Placing a well-known stand design, which has a significant mass and area in the center of antinode of the main mode of the upper deck of the guitar, inevitably has a damping effect on the processes of propagation of elastic vibrations in the resonator (body) of the guitar, as a result of which a decrease in the quality factor of the oscillating system, deterioration of all acoustic characteristics.

The construction of a classical guitar is known, in which the string holder (stand) in the protruding part is divided into three separate parts, in proportion to the number of strings placed on them, each of which is separately attached to the deck by an adhesive-threaded connection at a distance from each other, preserving the overall geometric shape the holder (application for the invention No. PCT / UA 2013/000126, publication date May 8, 2014). According to the physical concept, this constructive solution is designed to increase the amount of string energy transmitted to the deck by using energy parallel to the string vibration component. It is known that, when the string is excited, it rotates along a curve close to an ellipse. In the case when the string oscillates perpendicular to the plane of the deck, its vibrations (with the existing stand design) are best transmitted to the deck. In the case when the string oscillates parallel to the deck plane, the vibrations are practically not transmitted, since the stand has a considerable length, it is “clamped” by adjacent strings, as a result of which damping of this component of vibrations occurs. Cutting the stand, according to the author, should increase the mobility of the obtained three supports in a given plane of oscillation. In fact, the proposed technical solution does not improve the acoustic properties of the instrument, but worsens them. Cutting the stand as proposed in the application is unacceptable.

The stand, if it is glued correctly, in addition to the function of attaching the strings and transmitting the vibrations of the deck, is also a transverse spring that increases the elastic properties of the top deck, and thus partially compensates for the negative effect of the mass increase. By cutting the stand, the author eliminates its spring function, and it will act only as an additional weighting deck, which will inevitably lead to a further decrease in the quality factor of the oscillating system and other characteristics than was the case with the classical design.

The objective of the present invention is:

- improvement of acoustic characteristics of instruments;

- increase radiated sound power;

- reduction of production costs due to the improvement and simplification of production technology;

- improving the reliability and performance of tools.

The problem is solved in that the vibrations of the strings are transmitted without using a traditional stand. Instead, only the lower sill is installed on the outer surface of the deck. The function of a string holder and a spring is simultaneously performed by a footer located on the inner side of the upper deck, while through holes for each string are made in the upper deck and footer and a fixation unit is made on each string, which is inserted into the corresponding hole and fixed with a button. This design allows several times to reduce the mass of the central (most important for acoustic characteristics) region of the large oval of the upper deck, without lowering the elastic properties, and significantly reduce energy loss during transmission of vibrations from the strings to the body.

The invention is illustrated by drawings, which do not cover and, moreover, do not limit the entire scope of the claims of this technical solution, but are only illustrative materials of a particular case of execution, where:

- in FIG. 1 shows a view of the proposed design of an acoustic guitar;

- in FIG. 2 shows a longitudinal section AA shown in FIG. one;

- in FIG. 3 shows an embodiment of an acoustic guitar construction, different from FIG. 1, by different distances between the lower nut and the fixation point of the end of the string on the upper deck;

- in FIG. 4 - shows an embodiment of the base of the lower nut, resting on the upper deck with two points;

- in FIG. 5 shows an embodiment of an acoustic guitar structure different from FIG. 1 in that the lower sill is structurally divided into equal parts that are not in contact with each other in proportion to the number of strings resting on it;

- in FIG. Figure 6 shows an option for attaching the end of a nylon string using a “peg” or “button” type retainer.

An acoustic guitar consisting of a neck 1 with a top nut installed on it 2, frets 3, a head of a neck 4 with pegs 5 located on it, a body 6 consisting of a shell 7, an upper deck 8, a lower deck 9, a lower nut 10 installed separately on the outer surface of the upper deck 8 and resting on it through the base 11 along its entire length with two points, or divided into equal parts in proportion to the number of strings 15 resting on it, and the string holder, structurally made in the form of a footer 12, is located on the inner the surface of the upper deck 8, while in the pad 13, the upper deck 8 and the footer 12 there are through holes 14, for each string 15 located at the same or different distances from the lower nut 10, while the strings 15 are brought into the corresponding hole 14 and secured from stretching outward by a locking assembly 16, made at the end of each string, with a button 17 or a locking device 18 of the “spine” or “button” type. To fix the latch 18, the end of the nylon string is first brought into the hole on the outside of the deck, then pulled out through the resonant hole, after which a “spin” or “button” type latch is attached to it.

The operation of the proposed device, as well as its use for performing musical works, is completely identical to the traditional design, while significant advantages are achieved: operational, technological and, what is very important, acoustic.

In the proposed technical solution, the problem of tearing off the stand by the string tension force is solved automatically: there is no stand, there is no problem. The tension force of the strings acts on the footer, glued from the inside of the top deck, and this force presses the footer to the deck, and does not tear off the base of the stand, as is realized in the traditional design.

The invention reduces production costs by reducing the consumption of materials and production and technological operations for the manufacture of the stand and gluing it to the upper deck.

Due to the fact that the string holder is now “hidden” inside the guitar body, and the tension force of the strings only presses it against the deck, the material for making the footer, its shape, size, location, location of the springs can be selected in such a way that the listed factors will provide weight reduction the central (most significant for acoustics) region of the large oval of the upper deck several times. Hesitating, the strings do the job of “transferring” the mass of the deck, the less its mass, the less energy is spent for each period, the higher the quality factor of the system and the longer the duration of the oscillations.

The dimensions of the traditional stand are (180 × 30) mm, so its area is 5400 square meters. mm The vibrations of the strings transmitted through the lower sill to the deck are initially distributed over a significant area of the base of the stand, as a result of which the effect on the deck, leading to its elastic deformations, is negligible.

, где E - модуль упругости,

- величина деформации деки. Поскольку величина этих двух сил увеличивается, возрастает и амплитуда изгибных упругих механических колебаний, возбуждаемых в деке, что в свою очередь приводит к увеличению громкости звучания инструментов.In the proposed design solution, the area of the base on which the lower sill rests is (80 × 9) mm = 720 sq. mm Thus, the ratio of the areas of support of the lower sill in the traditional and proposed version will be 5400/720 = 7.5 times. From this it follows that the vibrations of the strings in the present invention will act directly on the upper deck (and not on the stand, as is implemented in the traditional version) and the strength of these vibrations increases significantly. In connection with the increase in the vibrational force of the strings transmitted through the lower nut, the deformation of the upper deck also increases, and accordingly, the elastic force that returns to the deck to its original state, which can be written as Hooke's law

where E is the modulus of elasticity,

- the amount of deformation of the deck. As the magnitude of these two forces increases, the amplitude of the bending elastic mechanical vibrations excited in the deck also increases, which in turn leads to an increase in the volume of the sound of the instruments.

Due to the fact that the main unit responsible for the transmission of string vibrations decreased several times both in area and in mass, the inertia of the system as a whole also decreased. As a result of this, string vibrations parallel to the body will be transmitted to the deck much better, due to which all acoustic characteristics of the guitar are improved.

The proposed invention expands the experimental possibilities in the direction of creating instruments with the best sound characteristics. So, it becomes possible to increase the shoulder of the application of force, depending on the wavelength of the particular string excited, by increasing the distance between the lower nut and the fixation point of the end of the string on the upper deck. Changing the number of support points of the lower nut, their area makes it possible to find optimal transmission options for all components of the vibrations of the strings of the upper deck. The dimensions of the footer, its shape, material, location, make it possible to achieve a reduction in the mass of the central part of the large oval of the upper deck, without compromising the elastic properties of the oscillatory system.

In the manufacture of the instrument, the guitar master at the stage of manufacturing the body parts, such as the upper deck, lower deck, makes certain resonant-frequency settings. After assembling the housing by grinding the upper and lower decks, this work can be continued. The purpose of these settings is to achieve the best sound settings. After gluing a traditional stand, the frequency characteristics of the instrument change in an unpredictable way. Given that sticking a stand in the technological cycle of making a guitar is almost the last operation, it is very problematic to make any frequency adjustments to the finished instrument. In the proposed design, the installation of the lower nut, due to its small mass and area does not affect the acoustic characteristics of the instrument, making it much easier to achieve the planned acoustic parameters on the finished instrument.

To summarize all that has been said, it is necessary to emphasize the following:

- in the traditional version, the stand has a damping effect when transmitting elastic vibrations from the nut of the deck, the consequence of this is the energy loss of the vibrations of the strings. In the proposed solution, the vibrations transmitted to the upper deck are much better, which leads to an increase in the amount of string energy that is converted into sound waves, resulting in an improvement in all acoustic characteristics of the guitar;

- unlike the traditional design in the proposed solution, exciting forces are applied to the upper deck from two sides, which contributes to a more effective, less inertial occurrence of bending elastic vibrations;

- due to the fact that the holder (foot) is located on the inside of the upper deck, its separation by tensioning the strings is completely eliminated.

Claims (7)

1. A plucked musical instrument - an acoustic guitar, consisting of a fretboard with an upper nut and frets mounted on it, a fret head with pegs located on it, strings, a body consisting of a shell, upper and lower decks, characterized in that the lower nut with a base installed separately on the outer surface of the upper deck, the base rests on the upper deck throughout its length, and the thread holder, structurally made in the form of a footer, is located on the inner surface of the upper deck, while in the upper deck and footer is a base provided with through holes for each string located at equal distances from the bottom of the nut and formed latch assembly on each string which is wound in the corresponding hole and fixed button. 2. A plucked musical instrument - an acoustic guitar according to claim 1, characterized in that the through holes for fixing the strings are located at different distances from the lower nut. 3. A plucked musical instrument - an acoustic guitar according to claim 1, characterized in that the lower threshold rests on the upper deck, through the base, with two points. 4. A plucked musical instrument - an acoustic guitar according to claim 1, characterized in that the through holes for fixing the strings are located at different distances from the lower nut, and the lower nut rests on the upper deck, through the base, with two points. 5. A plucked musical instrument - an acoustic guitar according to claim 1, characterized in that the lower threshold is structurally divided into equal parts that are not in contact with each other, in proportion to the number of strings resting on them. 6. A plucked musical instrument - an acoustic guitar according to claim 1, characterized in that the ends of the strings are inserted into holes of a smaller diameter and secured with a “spin” or “button” type retainer. 7. A plucked musical instrument - an acoustic guitar according to claim 1, characterized in that on the outer surface of the upper deck, separately from the base, there is an overlay with through holes for strings.

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