RU2504023C2 - Acoustic guitar with inner and outer housing - Google Patents

Abstract

FIELD: physics.

SUBSTANCE: string acoustic musical instrument has an inner housing consisting of upper and lower soundboards, sides, a heel, saddles and strings. The inner housing is placed in another (outer) larger housing, having the same shape as the inner housing and having only the lower soundboard and side, wherein an air gap is formed between the sides of both housings, as well as between lower soundboards thereof.

EFFECT: improved sound characteristics when using said instrument.

5 cl, 3 dwg

Description

A known acoustic string musical instrument (Japanese patent No. 4334833, 8G10D 1/00 dated 08/05/2002), in the housing of which a resonator of a lattice or honeycomb design is inserted to enhance the sound volume.

An acoustic string musical instrument is also known (Russian patent No. 22199592, 7G10D 1/08), in which, to obtain higher acoustic characteristics, for example, purity and saturation of the timbre, power and duration of sound, as well as reverb, the areas of the decks are separated by sound springs in certain proportions and the shell on the inside along the entire length of the body is equipped with dividing elements located on the basis of the ratio of the semitones of the tempered row symmetrically on both halves of the shell. Such a shell resonates at external frequencies and excites overtones, which are related to each other according to the law of the tempered series, mix with the overtones of the natural series, excited by decks, which leads to a phase difference in the oscillations and creates a reverb effect.

A disadvantage of the aforementioned musical instruments having upper and lower decks is that in the process of creating sound, the formation of sound waves is initiated by vibrations of only the upper deck of stringed musical instruments, while the resonating vibrations of the lower deck and shell are reduced to zero due to the fact that During the game, the lower deck and the shell are pressed against the clothes of the performer, which damps the resonant vibrations of the lower deck and the shell.

These circumstances adversely affect the sound of the instruments due to the fact that the acoustic characteristics of the sound waves of various registers lose the frequencies and amplitudes of oscillations that could be formed by the lower deck and the shell and mix and enrich the sound waves of other registers created by the upper deck.

A well-known classical string musical instrument is a classical guitar (patent No. 1709390, bull. No. 4 dated January 30, 1992), which we took as a prototype, containing a protective resonator fixed with a gap on the lower deck along its perimeter, made in the form of a plate in the form of the lower decks and fixed with a gap on the lower surface of the shell support made in the form of a plate in the shape of the middle of the lower part of the shell.

This protective resonator and support exclude, in the opinion of the inventor, the contact of the lower deck of the guitar and its shell with the body of the performer, improving acoustic characteristics and sound volume.

However, the disadvantage of the above prototype is that when playing on such an instrument, the performer’s body (hands) still contacts the upper part of the shell, which excludes its participation in the formation of sound waves of different registers, impoverishes the timbre and reduces the sound volume, and since the shell is tightly connected with its entire perimeter with the perimeter of the lower deck, then the formation of the sounds of the resonating registers of the lower deck is weakened. These circumstances negatively affect the possibility of a more complete use of the properties of the materials of the aforementioned instrument, reducing the level of their acoustic characteristics.

The objective of the invention is the creation of a stringed musical instrument, the design of which allows you to maximize the use of materials of decks, shells and the instrument as a whole to increase the power and duration of sound, as well as to improve the purity and saturation of the timbre and enhance the effect of reverb.

The problem is solved in that the body of a known string instrument, for example a guitar, consisting of two decks connected along the perimeter by a shell, forming an internal resonating volume (figure 1), is placed in an outer case (figure 2), consisting only of a shell and a bottom decks (bottom) and having internal dimensions around the circumference of the shell 4-100 mm larger than the external dimensions of the inner shell, and the height of the shell 4-10 mm greater than the height of the shell of the inner shell, so between the outer walls of the shell of the inner of the housing 1 (Fig. 1) and the inner walls of the shell of the outer casing 6 (Fig. 2), a gap of 2-50 mm is formed, into which wooden spacers 9 are glued tightly to the glue, which keep the casing 1 of the inner casing of the tool from contacting the casing 6 external housing.

Spacer dividing elements 9 are arranged according to the principle of halftone ratio on the basis of the law of the tempered scale, symmetrically on both halves of the shell, and the total length of the shell is taken as a scale.

The dimensions of the shell sections between the spacer elements 9 were obtained by calculations according to the formula: a = 2, where a is the calculated size of the shell section, and b is the length of the shell groove.

On the inner side of the deck 8 of the outer case, wooden gaskets 10 are glued, with a diameter of 5-10 mm and a height of 4-10 mm, on which the lower deck of the inner case rests. The number of gaskets 10 must be at least 6 (six) to ensure reliable support of the inner case, and they are located on deck 8 along the perimeter of the deck 13 of the inner case at points opposite the points of attachment of the sound springs 15 to deck 13.

Thus, between the lower deck 13 of the inner case and the deck 8 of the outer case, a gap of 4-10 mm is created, which eliminates the direct contact of these decks and, in combination with the gap between the shells 1 and 7, eliminates the damping effect of the deck 8 and shell 7, which increases the resonance Decks 13 and the volume of the instrument as a whole.

The invention is illustrated by drawings.

Figure 1 - the inner housing 1 of the tool, containing:

- 2 - the upper deck;

- 3 - a shell;

- 4 - neck;

- 5 - resonant hole.

Figure 2 - the outer case 6 of the tool, containing:

- 7 - a shell;

- 8 - deck (bottom);

- 9 - spacer elements;

- 10 - gaskets.

Figure 3 - section aa in figure 1:

- 11 - dumpling of the inner case 1;

- 12 - the heel of the neck 4 of the inner body;

- 13 - lower deck of the inner case;

- 14 - the frame of the upper part of the shell 7 of the outer casing.

Figure 3 shows the principal device of the invention, from which it can be seen that the inner casing 1, containing the upper 2 and lower 13 decks, neck 4 and casing 3, is installed in the outer casing 6, containing deck 8, casing 7, frame 14, spacers 9 and gaskets 10 (spacer elements 9 are shown in FIG. 2).

Unlike the known tools, the heel 12 of the neck 4 is attached to the glue 11 not from the outside of the body, but from the inside, which makes it possible to establish a gap between the shells 3 and 7 of any size, in particular in the range from 2 to 50 mm.

The rail 14, which is attached to the upper edge of the shell 7, has a width of 10 to 100 mm, depending on the gap between the shells 3 and 7, repeats the geometry of this shell, serves as a barrier to foreign objects getting into the gap between the shells 3 and 7 and is at the same time decorative decoration.

Between the rack 14 and deck 2 there is a gap of 2-4 mm for the unhindered passage of sound frequencies generated during the resonance of decks 2 and 13 and sections of the shell 3 located between the spacer elements 9.

The work of the inner case is based on the resonant excitation and amplification of the overtones and harmonics formed in the decks and the shell, which participate in the formation of the overall sound of the instrument.

The strings of the inner casing (not shown), brought to the active state by the performer, transmit their vibrations to the upper deck 2, which, acting as a membrane, causes an alternating decrease and increase in the density of the air in the inner casing 1, i.e. forms sound waves, under the influence of which the lower deck 13 and the shell 3 begin to resonate and enrich the timbre of a musical instrument with additional tones. And since in the present invention the damping effect of the shell 7 and deck 8 is completely neutralized, the sound volume generated by the inner housing 1 is increased.

The work of the shell, with wooden spacers 9 located perpendicular to the decks along the entire length of the shell, is symmetrical to both sides of the shell according to the law of the tempered sound row a = 2, where a is the distance between two adjacent elements 9, b is the length of the shell (full inner circumference of the shell 7), consists in the excitation of overtones, related to each other according to the above law, i.e. overtones of the temperamental series, which, together with the overtones of the natural series, excited by decks with the absolute value between them, leads to a difference in the phases of the oscillations in the case and creates a reverberation effect.

At the same time being stiffeners, the spacer elements 9 prevent the resonance of the shell at low frequencies in the direction perpendicular to the surface of the shell, thereby reducing its damping effect and increasing the sound pressure of the housing as a whole. A shell with such elements resonates at high frequencies, enhances overtones and transfers well the low-frequency vibrations of the audio range from deck to deck.

The stringed musical instrument created on the basis of the invention, having an inner case 1 consisting of a top 2 and a bottom 13 dec, a neck 4 and a shell 3, as well as an outer case 6 consisting of a lower deck 8 and a shell 7, spacers 9 and spacers 10, the shielding inner case 1 (internal volume) and in contact with it only through the narrow contacts of the spacer elements 9 and thereby eliminating the negative influence of the performer’s body and clothing on the internal volume and acoustic properties of the instrument, has a dense strong sound, pain th sound pressure bright timbre, saturated, long duration of effect sound and reverberation.

The present invention made it possible to use a thinner lower deck 13 of the inner case and create in the decks the conditions for the excitation and amplification of overtones of the natural series, in the shell - overtones of the temperamental series, in the inner case - the conditions for the manifestation of the reverb effect, as well as to create a more durable instrument for optimal distribution of mechanical loads in decks and the instrument as a whole and use strings of different masses and tension.

When the applicant conducted a patent information search, no sources were found containing information on technical solutions identical to the present invention, which allows us to conclude that it meets the criterion of "novelty."

Claims (5)

1. String acoustic musical instrument containing an inner case, consisting of upper and lower decks, shells, neck, sills and strings, characterized the fact that the inner casing is installed in another (outer) larger casing, exactly repeating the geometry of the inner casing and having only the lower deck and the casing, and an air gap is formed between the casing of both buildings and also between their lower decks. 2. String acoustic musical instrument according to claim 1, characterized the fact that the gap between the shells of both buildings is formed by installing spacers between them, mounted vertically along the entire surface of the shells. 3. String acoustic musical instrument according to claim 1, characterized in that the gap between the lower deck of the inner case and the deck of the outer case is formed by installing gaskets. 4. String acoustic musical instrument according to claim 1, characterized in that the heel of the neck of the inner body is attached to the glue from the inside of the inner body. 5. String acoustic musical instrument according to claim 1, characterized the fact that the upper edge of the shell of the outer casing has a narrow strip of solid material (for example, wood) attached to it, repeating the geometry of the shell along its entire length.

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