RU34053U1 - Sound device - Google Patents

Description

At the construction site m voshcheyumdmosh seyiti Description of the invention. The invention relates to acoustic equipment, in particular to acoustic systems of sound reproducing equipment and can be used in high quality sound reproducing systems. A known acoustic system containing a housing with a hole for the speaker made in the form of a hollow parallelepiped and equipped with at least one partition located parallel to the base of the housing (V.A. Vasiliev Radio amateurs - village club, M., Radio and communications, 1983., p55, fig. 57) In this speaker system, the partition prevents the appearance of gaps at the joints of the body parts, which leads to the reduction of extraneous overtones during the reproduction of the zosos signal. The disadvantages of this speaker system, as well as of all closed-type speakers, are: -increase the resonant frequency of the speaker when installed in a closed case, -increase the lower cut-off frequency, - decay of sound pressure in the low region often. The technical result of the application and the foregoing invention is to reduce the resonant frequency of closed-type speaker systems and to improve the quality of your system. The essence of the invention lies in the fact that it is proposed in the device for reproducing sound that contains a housing with a hole for a loudspeaker made in the form of a hollow parallelepiped and provided with at least one partition located parallel to the base of the housing inside the enclosure of a closed type speaker system MPK Н 04 R 1 / 28

place the Helmholtz resonator, the value of the acoustic impedance of which depends on the frequency of the sound wave emitted by the loudspeaker.

In FIG. 1 shows a longitudinal section of a device for reproducing sound or speakers.

A device for reproducing sound or a closed-type speaker system includes a housing 1. A loudspeaker 2 is located on the front panel of the housing. A panel 3 is installed inside the housing between the front and rear panels. Panel 3, the rear panel 4, the upper and lower, and the side panels of the housing limit camera 5 to volume V. In panel 3, holes were made that form the tunnels of the Helmholtz resonator with the cross-sectional area S and length L. The frequency of tuning the Helmholtz resonator where Sv is the speed of sound

defined by the thickness of the panel 3, volume V, the radius of the holes b and their number.

The device operates as follows. AC flow through coil winding

causes the appearance of a force that drives the speaker cone 2. Oscillations of the diffuser create sound waves. Waves emitted from the outer surface of the diffuser propagate in the environment. Waves from the inner surface of the diffuser propagate inside the housing and reach the panel 3, which provides resistance to radiation. In this case, the Helmholtz resonator begins to work. For waves whose propagation frequency is equal to the resonator tuning frequency, acoustic

2

Rezr Szv / 27glG8 / b U

resistance increases, which leads to a decrease in the propagation velocity of these waves. The result of a decrease in speed (Sv) is an increase in air flexibility (Sv) inside the body volume (Vo). where P is the density of air. Acoustic Flexibility Ratio of Loudspeaker Suspensions

(Cas) and air in a closed housing (Cav) is called the coefficient of flexibility

and Cas / Sav

Closed Enclosure Resonant Frequency (Fc)

and the natural resonant frequency of the loudspeaker (Fs) are related to the coefficient of flexibility, and the ratio

(a + l)

The natural resonant frequency of the speaker (Fs) is set

constructively and does not change.

Therefore, with a decrease in the coefficient of flexibility a:

- the resonant frequency of the speaker in the closed

case

- the lower cutoff frequency will decrease;

-Increased sound pressure in the low frequency region.

Qi (in4

Sav Wo / (RSzv)

Claims (1)

A closed-type acoustic system comprising a housing made in the form of a hollow parallelepiped, a hole is made on the front panel of the housing in which a loudspeaker is placed, at least one panel is installed inside the housing parallel to the base of the housing, and the panel contains holes that form Helmholtz resonator tunnels, and a Helmholtz resonator is formed inside the housing, the value of the acoustic impedance of which depends on the frequency of the sound wave emitted by the loudspeaker.