KR101727020B1

KR101727020B1 - Hybrid type dynamic speaker having two or more nozzle hole

Info

Publication number: KR101727020B1
Application number: KR1020160021355A
Authority: KR
Inventors: 김주영
Original assignee: 레프릭오디오주식회사
Priority date: 2016-02-23
Filing date: 2016-02-23
Publication date: 2017-04-14
Also published as: WO2017146323A1

Abstract

A hybrid type dynamic speaker having two or more nozzle holes is disclosed. A hybrid dynamic speaker having at least two nozzle holes according to the present invention is characterized in that a receiving space which is opened to one side is formed and an outer seating jaw is protruded at an inner side of an inlet side of the receiving space, And a nozzle hole having a size smaller than that of the installation space is formed at an end of the installation section, and a nozzle hole having a size smaller than the outer installation jaw A frame having an inner seating surface formed on an outer surface of the mounting portion of the frame; A magnet disposed in close contact with an inner wall of the accommodating space so as to maintain a gap with the yoke; and a magnet provided on the bottom of the accommodating space, A plate provided between the magnet and the outer seating jaw and a through hole formed at the center for penetrating a part of the mounting portion to be seated in the outer seating jaw and the inner seating jaw and positioned between the magnet and the yoke, A speaker for generating a full-band sound, comprising: a diaphragm having a coil; a cap having a plurality of full-width sound discharge holes and being coupled to the frame while pressing the diaphragm; And a balanced amateur driver installed in an installation space of the installation part such that a part of the balanced amateur driver is exposed to the nozzle hole, wherein the balanced amateur driver is composed of 2 to 10, And the sound sources reproduced from the respective balanced amateur drivers are formed in a number corresponding to the number of the balanced amateur drivers so that sound separation is performed without interfering with each other. According to the present invention, two or more nozzle holes are formed in a mounting portion of a frame provided with a speaker, and a balanced amateur driver is provided in each nozzle hole to separate the three-way speaker including the full- The balanced amateur driver reproduces and discharges the sound through the different nozzle holes that are separated from each other. As a result, it is possible to improve the sound quality of the sound source, The interference can be minimized and the sound can be separated and separated to provide an effect that the regenerative power can be improved.

Description

HYBRID TYPE DYNAMIC SPEAKER HAVING TWO OR MORE NOZZLE HOLE "

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hybrid type dynamic speaker having two or more nozzle holes and more particularly to a hybrid type dynamic speaker having a dynamic driver as a balanced amateur driver as a woofer and a tweeter speaker and a full- By configuring two or more amateur drivers, each of the balanced amateur drivers having the same number of nozzles as the number of each balanced amateur driver so that they are installed in different nozzle bores, the sound sources output from each balanced amateur driver can be different In addition to being able to be discharged from the nozzle hole, individual tuning such as enlarging or reducing the size of each nozzle hole or installing a damper on each nozzle hole can be performed, thereby minimizing the mutual interference of the sound sources, Raise And more particularly, to a hybrid type dynamic speaker having two or more nozzle holes capable of improving regenerative power and capable of efficiently controlling sound pressure and crossover positions.

Generally, 2-way speakers have bass speakers and treble speakers, which gives the listener the best sound quality. However, as shown in FIGS. 1 and 2, such a two-way speaker is structurally structured such that the sound transmission speed due to each arrangement distance (position) of the speakers varies, There was a problem of heterogeneity.

That is, in the two-way speaker, the dynamic driver 1 for outputting a low-frequency sound and the balanced amateur driver 2 for outputting a high-frequency sound are structurally arranged at different positions, There is a problem that a phase difference is generated which is different from the phase difference, and thus a negative distortion and a sense of heterogeneity are generated.

As another prior art, Korean Patent No. 10-1309072 (Attachment: 2013.10.14) filed by the present applicant discloses a sound generator holder structure of a two-way earphone. 3, the sound generator holder structure of the two-way earphone includes a rear body 10 and a front body 20, and a cover 30 made of a cushion material is attached to the front body 20, A balanced transducer 50 for bass and a dynamic transducer 60 for treble as a treble generator are installed as one holder 40 in the front and rear bodies 20 and 10, The holder 40 includes a cup holder-type balanced armature transducer retaining ring 41 and a high-sounding dynamic transducer 41 bending at a front side of the retaining ring 41, And a small high dynamic range transducer (60) is elastically fixed to the holding piece (42A) of the fixing piece (42), and the fixed piece 42 is formed by a gap retaining piece 42B, And by keeping the gap between the retaining ring 41, the nipping pieces (42A) is configured to be positioned over the center portion of the fixing ring (41).

However, in this prior art, since the balanced transducer 50 for bass and the dynamic transducer 60 for treble, which are treble generators, are disposed at a predetermined distance, There was a problem that heterogeneity was generated.

As a means for solving such a problem, a hybrid speaker unit is disclosed in Korean Patent No. 10-1460170 (public announcement: 2014.11.20). 4, the hybrid speaker unit 100 is provided with a receiving portion 112 that is open to one side, and is installed at the center of the receiving portion 112, A permanent magnet 140 fixed to the yoke 130 and a permanent magnet 140 fixed to the yoke 130. The permanent magnet 140 is installed on the bottom of the frame 110, And a yoke 130 disposed between the permanent magnet 140 and the yoke 130. The plate 150 is installed in contact with the yoke 130, A diaphragm 200 for coupling the coil 160 to output a low sound level and a cap (not shown) coupled to the frame 110 to cover the inlet of the receiving portion 112 by piercing at least one sound- 170 installed on the mounting portion 114 so as to be disposed at the same position as the diaphragm 200, It has a configuration including a former for the speaker 300. The

As described above, a mounting portion 114 having an installation hole 114A and an exposure hole 114B is formed at the center of a dynamic driver (permanent magnet, voice coil, diaphragm, etc.) for outputting low- (Balanced amateur driver) for the high-frequency band are disposed in the center of the diaphragm so that the high-frequency speakers for outputting the high-frequency band are arranged in the same line without a distance from the dynamic driver according to the arrangement, It is possible to reduce the phase difference due to the arrangement distance of the two speakers outputting different frequency bands, thereby eliminating the distortion and heterogeneity of the sound.

However, when the conventional speaker is composed of a dynamic speaker for outputting a low-frequency sound and a balanced amateur driver for outputting a high-frequency sound, the low and high sounds can be separated and output without mutual interference. However, When two or more amateur drivers are configured, the sound sources output from each balanced amateur driver cause mutual interference.

It consists of a balanced amateur driver for the woofer and a balanced amateur driver for the tweeter, or a balanced amateur driver for the subwoofer and a balanced amateur driver for the woofer and a balanced amateur driver for the tweeter in the central area of the dynamic speaker for outputting low- Or a balanced amateur driver for a subwoofer, a balanced amateur driver for a woofer, a balanced amateur driver for a tweeter, a balanced amateur driver for a scorcher and a balanced amateur driver for a tweeter, each balanced amateur driver is connected to a single nozzle ball There is a problem that the sound reproduced by each balanced amateur driver is interfered with each other or the sound separation performance is lowered and the sound reproducibility is lowered.

Further, in the case where the balanced amateur driver is constituted by two or more, it is difficult to fine-tune individual tuning of each balanced amateur driver by constituting one nozzle hole, and thus the sound pressure control and the crossover position can not be efficiently controlled will be.

. Korean Patent No. 10-1309072 (Notification date: October 13, 2013) . Korean Patent No. 10-1460170 (Notification date: Nov. 20, 2014)

SUMMARY OF THE INVENTION It is an object of the present invention to provide a hybrid dynamic speaker in which when a balanced amateur driver is provided as two or more high-frequency speakers, the sound sources output from each balanced amateur driver can be prevented from mutual interference or interference can be minimized, And to provide a means by which each of the balanced amateur drivers can be installed in different nozzle holes so as to increase the separation and improve the regenerative power.

It is also an object of the present invention to provide means for finely and efficiently adjusting the sound pressure and crossover position by individually tuning each nozzle hole.

The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to at least partially solve the problems in the conventional arts. It can be understood.

According to an aspect of the present invention, there is provided an air conditioner comprising: a housing space opened to one side of the housing space; an outer seating protrusion protruding from an inner side of an inlet side of the housing space; And a nozzle hole having a size smaller than that of the installation space is formed at an end of the installation part, and a nozzle hole having a size smaller than that of the installation space is formed on an outer side of the installation part at an inner side A frame on which a seating jaw is formed; A magnet disposed in close contact with an inner wall of the accommodating space so as to maintain a gap with the yoke; and a magnet provided on the bottom of the accommodating space, A plate provided between the magnet and the outer seating jaw and a through hole formed at the center for penetrating a part of the mounting portion to be seated in the outer seating jaw and the inner seating jaw and positioned between the magnet and the yoke, A speaker for generating a full-band sound, comprising: a diaphragm having a coil; a cap having a plurality of full-width sound discharge holes and being coupled to the frame while pressing the diaphragm; And a balanced amateur driver installed in an installation space of the installation part such that a part of the balanced amateur driver is exposed to the nozzle hole, wherein the balanced amateur driver is composed of 2 to 10, And the sound sources reproduced from the respective balanced amateur drivers are respectively formed in a number corresponding to the number of the balanced amateur drivers so that the sound sources isolated from each other are not interfered with each other. Lt; / RTI >

The nozzle hole may be on a plane such as the full-width sound hole formed in the cap.

In the installation space, a partition wall for separating each of the adjacent balanced amateur drivers may be integrally formed with the frame.

The mounting space may be provided with a partition member for separating each of the adjacent balanced amateur drivers.

The nozzle hole may be provided with a damper made of a mesh or fabric for adjusting the sound pressure and crossover position generated from the balanced amateur driver.

The nozzle holes may have the same or different sizes in order to adjust negative pressure and crossover position of negative sound generated from the balanced amateur driver.

The nozzle hole may be located in a through hole region formed at the center of the diaphragm.

According to the present invention, two or more nozzle holes are formed in the mounting portion of the frame provided with the full-band generating speaker, and balanced amateur drivers are provided in the respective nozzle holes so that the three-way speaker including the full- Of course, it is possible to realize a speaker of four or more ways, and thereby it is possible to provide various effects such that various high-pitched sounds can be reproduced.

In addition, since each balanced amateur driver reproduces and discharges sound through different nozzle holes separated from each other, interference between the sound sources can be minimized, sound can be divided and separated, and the reproducibility can be improved . &Lt; / RTI >

In addition, each balanced amateur driver is individually mounted in each nozzle hole to facilitate individual tuning, such as adjusting the size of the nozzle hole through which the sound is emitted, attaching or removing the damper, or changing the material of the damper And it is possible to provide an effect that the sound pressure control and the crossover position can be efficiently controlled.

1 to 4 are schematic views showing a conventional two-way speaker.
5 is a schematic sectional view showing a hybrid type dynamic speaker having two or more nozzle holes according to the first embodiment of the present invention.
Fig. 6 is a schematic front view showing a hybrid type dynamic speaker having two or more nozzle holes shown in Fig. 5. Fig.
FIGS. 7 and 8 are schematic front views showing a state in which three nozzle holes and four nozzle holes are formed in the mounting portion shown in FIG.
9 and 10 are schematic enlarged cross-sectional views showing a state where the partition space and the partition member are provided in the installation space shown in FIG.
Fig. 11 is a graph for explaining a hybrid type dynamic speaker having two or more nozzle holes shown in Fig. 5. Fig.
12 and 13 are sectional views for explaining a state where a partition or a partition wall member is provided in a frame installation space.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description of the present invention, the well-known functions or constructions are not described in order to simplify the gist of the present invention.

5 is a schematic cross-sectional view showing a hybrid type dynamic speaker having two or more nozzle holes according to a first embodiment of the present invention, and Fig. 6 is a cross-sectional view of a hybrid dynamic speaker having two or more nozzle holes shown in Fig. 5 1 is a schematic front view showing a hybrid type dynamic speaker.

5 and 6, a hybrid type dynamic speaker 500 having two or more nozzle holes has a housing space S1 in which a full-band generating speaker 520 is installed and a balanced amateur driver 500 for generating a treble sound. A speaker 520 for generating a full-range sound in a receiving space S1 and a balanced amateur driver (not shown) provided in the mounting portion 512 530, and the mounting portion 512 has two or more balanced armature drivers 530 and a corresponding number of nozzle holes 512A, respectively.

This will be described more specifically.

The frame 510 is formed with a receiving space S1 which is open at one side to receive the components constituting the full band generating speaker 520 and an outer receiving jaw 514 is formed at the inner side of the receiving space S1. A mounting portion 512 having an installation space S2 protruded in the direction facing each other and opened in a direction opposite to the accommodation space S1 is protruded toward the entrance from the bottom of the accommodation space S1 A nozzle hole 512A having a size smaller than the installation space S2 is formed at an end of the mounting portion 512 and an inner mounting jaw 514 is formed on the outer surface of the mounting portion 512 at the same position as the outer mounting jaw 514. [ (512B) are formed.

The diaphragm 521, the plate 529, and the diaphragm 522 having the PCB 522, the yoke 524, the magnet 526, and the voice coil 528, which constitute the full- A cap 523, and the like.

The outer seating jaw 514 is provided for seating the cap 523 together with the inner seating jaw 512B. When the frame 510 is formed in a cylindrical shape or in a rectangular barrel shape, As shown in Fig. The degree of protrusion of the outer mounting step 514 is satisfactory as long as the diaphragm 521 can be stably mounted.

The mounting portion 512 has an installation space S2 that is opened in a direction opposite to the accommodation space S1 and two or more balanced amateur drivers 530 are provided at the end portion in the open direction of the accommodation space S1. A number of nozzle holes 512A are formed corresponding to the number of balanced amateur drivers 530, respectively. The nozzle hole 512A is formed to have a smaller size than the installation space S2. This is to match the shape of the balanced amateur driver 530 where the body 532 is large and the output 534 is small. That is, the body 532 of the balanced armature driver 530 is located in the installation space S2 and the output portion 534 is located in the nozzle hole 512A.

This nozzle hole 512A is formed to be positioned at the same position as the full-width sound discharge hole 523A of the cap 523 installed in the frame 510. [ This is to minimize the heterogeneity due to the phase difference by causing the sound outputted from the full-band generating speaker 520 and the sound outputted from the balanced amateur driver 530 to be outputted at the same position (without phase difference). To this end, each nozzle hole 512A is formed at the same height as the inner seating step 512B or at the end of the projection 512C projecting from the inner seating step 512B as shown in Fig.

Meanwhile, as shown in FIGS. 5 and 6, the nozzle holes 512A may be formed of two nozzles, and three or four nozzle holes 512A may be formed as shown in FIG. 7 and FIG. At this time, each of the nozzle holes 512A should be located in the through hole 521A of the diaphragm 521. [ This is because the nozzle holes 512A are formed close to each other in the area of the through hole 521A so that they are separated from the sound emitted from the full band sound discharge hole 523A and are separated from the center of the diaphragm 521 by a high tone And a sound different from the generated sound).

As described above, by forming two or more nozzle holes 512A (approximately 2 to 10), it is possible to adjust the size such that the hole size of each independent nozzle hole 512A is formed to be large or small, As shown in FIG. 11, and a separate damper 550, such as a nozzle hole 512A or an output portion 534, as shown in FIG. 13, and a crossover position Can be efficiently controlled.

That is, conventionally, in the case of constructing a 3-way speaker, since the position and the sound pressure of the crossover are adjusted by using the capacitor and the resistor, there is a limitation in fine tuning (tuning) The number of the nozzle holes 512A may be set to a number corresponding to the number of the balanced amateur drivers 530 to individually adjust the hole size of each nozzle hole 512A by individually making each nozzle hole 512A, The nozzle holes 512A can be individually tuned by providing a damper 550 made of a mesh or a fabric as required. Thus, the sound pressure control (decibel adjustment), the volume and the crossover position can be efficiently controlled.

For example, when the balanced amateur drivers 530 installed in each nozzle hole 512A are constituted by the balanced amateur driver 530 for the woofer and the balanced amateur driver 530 for the tweeter, the balanced amateur driver 530 for the woofer The nozzle hole 512A in which the balanced amateur driver 530 for the tweeter is installed may be made large or small or a damper 550 may be provided as necessary to individually adjust the sound hole It is possible not only to finely adjust the sound pressure to be discharged to each nozzle hole 512A by forming the size of the nozzle hole 512A to be large or small or by providing the damper 550 individually to perform tuning individually, By finely tuning the nozzle holes 512A, a balance and amateur driver 5 for the yaw and tweeter, which is discharged from the balanced amateur driver 530 for the woofer 30 can be finely adjusted. That is, mutual interference of the sound sources generated from each balanced amateur driver 530 can be minimized, and sound separation can be enhanced to improve the reproduction power.

Here, the damper 550 is made of mesh or cloth, and may be installed at the inlet of the nozzle hole 512A as needed to adjust the sound pressure or adjust the crossover position. That is, by providing the damper 550 at the inlet of the nozzle hole 512A, the sound emitted from the nozzle 550 interferes with the damper 550, thereby reducing the amount of noise to be discharged. The reduction can also be controlled. Accordingly, the negative pressure discharged to each nozzle hole 512A can be efficiently controlled by using the damper 550 or the material of the damper 550 installed, which is formed by individually forming the nozzle holes 512A It becomes possible because it is.

At this time, the damper 550 may be installed in the nozzle hole 512A as shown in FIG. 12, but it may be installed in the output portion 534 of the balanced armature driver 530 as shown in FIG. 13 .

As described above, since the nozzle holes 512A are individually formed, the sizes of the respective nozzle holes 512A are adjusted so as to adjust the negative pressure and the crossover position of negative sound generated from the respective balanced amateur drivers 530. [ May be the same or different from each other.

9, a partition wall 516 for separating neighboring balanced amateur drivers 530 may be integrally formed with the frame 510 in the installation space S2, as shown in FIG. 9 . Since the adjacent balanced amateur drivers 530 are isolated from each other by the partition 516, the degree of negative separation can be further improved.

In addition, as shown in Fig. 10, a partition member 560 for separating each adjacent balanced amateur driver 530 may be installed in the installation space S2. Such a partition member 560 prevents vibrations and the like from being transmitted to neighboring balanced amateur drivers 530 as well as preventing each balanced amateur driver 530 from touching each other between neighboring respective balanced amateur drivers 530 Thereby preventing interference.

The full-range speaker 520 is provided in the accommodation space S1 to generate a full-range sound from bass to midtone and treble, and discharges it to the full-range sound discharge hole 523A of the cap 523, A PCB 522 provided on the bottom or back surface of the space S1, a yoke 524 provided on the outer surface of the bottom of the accommodating space S1 and the mounting portion 512, A plate 529 provided between the magnet 526 and the outer seating step 514 and a plate 529 provided at the center of the mounting part 512 And a voice coil 528 disposed at the center between the magnet 526 and the yoke 524 and seated on the outer seating jaw 514 and the inner seating jaw 512B A diaphragm 521 and a plurality of full-width sound ejection holes 523A are provided for pressing the diaphragm 521 to a cap 523 coupled to the frame 510 Lure. Although the full-band generating speaker 520 may be used for generating bass, the present invention will be described on the basis of what is used for generating a full-band sound. The full-range-generating speaker 520 is a general configuration, and thus a detailed description thereof will be omitted.

The balanced amateur driver 530 is for generating different sounds, and when composed of two, it is configured for a woofer and a tweeter, and when composed of three, it can be configured for a subwoofer, a woofer, and a tweeter have. That is, in case of two bass, one bass, one bass, and three bass, one middle, and one treble. In case of four bass, one bass, one bass, It can be divided into one tall and one tall. At this time, as the number of the balanced amateur drivers 530 increases, the sound can be reproduced in detail. That is, it is possible to reproduce a wider range.

5, the balanced amateur driver 530 may be divided into a body 532 and an output unit 534, and may be provided at the end of the output unit 534, as shown in FIG. 13, A damper 550 may be installed on the inner side as required.

Each of these balanced amateur drivers 530 is inserted and coupled to the installation space S1 so that the output portion 534 is fitted into the nozzle hole 512A.

The hybrid dynamic speaker 500 having two or more nozzle holes according to the present invention is described below.

First, a full-band generating speaker 520 is installed in the receiving space S1 of the frame 510. [ Then, each of the balanced amateur drivers 530 is inserted into the installation space S2 so that the output portion 534 is fitted into the nozzle hole 512A. As described above, the output unit 534 of each balanced amateur driver 530 is installed and connected to the nozzle hole 512A independent of each other, and each component constituting the full-range generating speaker 520 is connected to the receiving space S1 Assembly of the hybrid type dynamic speaker 500 having two or more nozzle holes is completed.

In this hybrid type dynamic speaker 500 having two or more nozzle holes, two or more balanced amateur drivers 530 are disposed in the center of the full-range generating speaker 520 via respective nozzle holes 512A It is possible to reproduce a wide band, and the mutual interference of the sound sources can be minimized.

Each of the nozzle holes 512A is formed separately from each other and a balanced amateur driver 530 is installed in each of the nozzle holes 512A so that the sizes of the nozzle holes 512A are different from each other, Not only can the sound pressure and tone emitted through each nozzle hole 512A be finely adjusted through tuning operations such as forming a damper 550 according to necessity, The crossover position of the generated sound can be efficiently finely adjusted.

Therefore, it is possible to improve the reproducibility of sound through the hybrid type dynamic speaker 500 having two or more nozzle holes.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It is obvious to those who have. Accordingly, it should be understood that such modifications or alterations should not be understood individually from the technical spirit and viewpoint of the present invention, and that modified embodiments fall within the scope of the claims of the present invention.

500: Hybrid dynamic speaker
510: frame 512: installation part
512A: nozzle hole 512B: inner mounting jaw
512C: protrusion 514: outer seating jaw
516:
520: full-range speaker 522:
524: yoke 526: magnet
528: voice coil 529: plate
521: diaphragm 521A: through hole
523: Cap 523A: full-width sound discharge ball
530: Balanced Amateur Driver 532: Body
534: Output section 550: Damper
560: partition member

Claims

And an installation space formed in the inside of the receiving space is formed in the inside of the receiving space, and an external mounting protrusion is formed on the inner side of the inlet side of the receiving space, A nozzle hole having a size smaller than that of the installation space is formed at an end of the installation part and an inner installation step is formed on an outer side surface of the installation part at the same position as the outer installation step;
A magnet disposed in close contact with an inner wall of the accommodating space so as to maintain a gap with the yoke; and a magnet provided on the bottom of the accommodating space, A plate provided between the magnet and the outer seating jaw and a through hole formed at the center for penetrating a part of the mounting portion to be seated in the outer seating jaw and the inner seating jaw and positioned between the magnet and the yoke, A speaker for generating a full-band sound, comprising: a diaphragm having a coil; a cap having a plurality of full-width sound discharge holes and being coupled to the frame while pressing the diaphragm; And
And a balanced amateur driver installed in an installation space of the installation part such that a part thereof is exposed to the nozzle hole,
The balanced amateur driver consists of 2 to 10,
The nozzle hole
Wherein each of the balanced amateur drivers is disposed in a spaced apart relationship so that sound sources reproduced from the respective balanced amateur drivers are independently formed in a number corresponding to the number of the balanced amateur drivers so that sound separation is performed without interfering with each other ,
Hybrid dynamic speaker with two or more nozzle holes.

The method according to claim 1,
The nozzle hole
Wherein the cap is located on the same plane as the full-width sound discharge hole formed in the cap.
Hybrid dynamic speaker with two or more nozzle holes.

3. The method according to claim 1 or 2,
In the installation space,
Characterized in that a partition for separating each of said adjacent balanced amateur drivers is formed integrally with said frame,
Hybrid dynamic speaker with two or more nozzle holes.

3. The method according to claim 1 or 2,
In the installation space,
Characterized in that a partition member for separating each of said adjacent balanced amateur drivers is provided.
Hybrid dynamic speaker with two or more nozzle holes.

3. The method according to claim 1 or 2,
In the nozzle hole,
And a damper made of a mesh or fabric for adjusting the sound pressure and the crossover position generated from the balanced amateur driver.
Hybrid dynamic speaker with two or more nozzle holes.

6. The method of claim 5,
The nozzle hole
Wherein the first and second balanced amature drivers are formed to have the same or different sizes in order to control negative sound pressure and crossover position generated from the balanced amateur driver.
Hybrid dynamic speaker with two or more nozzle holes.

The method according to claim 6,
The nozzle hole
Wherein the vibration plate is located in a through hole area formed at the center of the diaphragm.
Hybrid dynamic speaker with two or more nozzle holes.