CN113055513A

CN113055513A - Mobile phone and loudspeaker box for electronic equipment

Info

Publication number: CN113055513A
Application number: CN202110239876.1A
Authority: CN
Inventors: 考文; 冯雷皓; 邵帅
Original assignee: Hisense Mobile Communications Technology Co Ltd
Current assignee: Hisense Mobile Communications Technology Co Ltd
Priority date: 2021-03-04
Filing date: 2021-03-04
Publication date: 2021-06-29

Abstract

The application discloses a mobile phone and a loudspeaker box for electronic equipment, wherein the mobile phone comprises the loudspeaker box, and the loudspeaker box comprises a loudspeaker body, a front cover plate and a rear cover plate; the front cover plate and the loudspeaker body enclose a front sound cavity which influences a high-frequency resonance point of the loudspeaker body, and the rear cover plate and the loudspeaker body enclose a rear sound cavity which influences a low-frequency resonance point of the loudspeaker body; the front cover plate is provided with a sound outlet hole communicated with the front sound cavity; and a resonant cavity is further arranged on the front cover plate around the front sound cavity and is communicated with the front sound cavity. The structural design of the loudspeaker box can effectively improve the sensitivity of a high-frequency resonance point of the loudspeaker, change the resonance frequency and avoid generating sharp distortion and noise.

Description

Mobile phone and loudspeaker box for electronic equipment

Technical Field

The application relates to the technical field of electronic equipment, in particular to a mobile phone. Furthermore, the application relates to a loudspeaker enclosure for an electronic device.

Background

In the technical field of mobile phones, a common speaker box comprises a front cover plate, a speaker body, an FPC (flexible printed circuit) or a welding wire and a rear cover plate. The space between the rear cover plate and the loudspeaker body is a rear sound cavity which mainly determines the low-frequency resonance point of the loudspeaker; the part between the front cover plate and the loudspeaker body is a front sound cavity and radiates outwards through the sound outlet hole, and the part mainly determines the high-frequency resonance point of the loudspeaker.

Due to the limitation of a design structure, a front sound cavity of the loudspeaker is generally in a long and narrow structure, the resonance frequency of the front sound cavity is generally within the range of 3000-7000 Hz, the range is a high-frequency part of human ear hearing and is also a normal working frequency range of the loudspeaker, and due to the resonance, a peak exists in the range of 3000-7000 Hz of the mobile phone loudspeaker. The sensitivity of the peak is more than ten and more dB higher than that of other frequency bands, so that the sensitivity of each frequency band which does not meet the requirement of transmission distortion-free is the same, and the high frequency of the mobile phone loudspeaker is sharp. Meanwhile, the higher harmonics generated by the vibration of other frequencies will be amplified by the peak to cause noise.

That is, in the design of the mobile phone speaker, due to the limitation of the size of the whole mobile phone, the sound outlet hole of the speaker is narrow, the cavity is long and thin, the resonant frequency of the air pipeline is close to the sound frequency, the speaker resonates with the cavity when sounding, a high-frequency resonant peak generally exists in the micro speaker box, the peak can cause the subjective auditory sensation to generate obvious discomfort and sharp sound, and distortion of low-frequency points is amplified when the distortion is close to the frequency, so that noise is caused.

Disclosure of Invention

The technical problem that this application will be solved is for providing a cell-phone, and the structural design of the speaker box of this cell-phone can be effectively the sensitivity of speaker high frequency resonance point, changes resonant frequency, avoids producing sharp-pointed distortion and noise. In addition, another technical problem to be solved by the present application is to provide a speaker box for an electronic device.

In order to solve the technical problem, the application provides a mobile phone, which comprises a speaker box, wherein the speaker box comprises a speaker body, a front cover plate and a rear cover plate; the front cover plate and the loudspeaker body enclose a front sound cavity which influences a high-frequency resonance point of the loudspeaker body, and the rear cover plate and the loudspeaker body enclose a rear sound cavity which influences a low-frequency resonance point of the loudspeaker body; the front cover plate is provided with a sound outlet hole communicated with the front sound cavity;

and a resonant cavity is arranged on the front cover plate around the front sound cavity and is communicated with the front sound cavity.

In a specific embodiment, a first concave part is opened on one side of the front cover plate facing the loudspeaker body, and the loudspeaker body covers the first concave part to form the front sound cavity; the resonant cavity is arranged on the periphery of the first concave part except the other three sides on one side of the sound outlet hole.

In a specific implementation manner, a third recessed portion is formed on a side of the front cover plate facing away from the speaker body, the third recessed portion is covered with a cover plate, and the cover plate and the third recessed portion enclose the resonant cavity.

In a specific embodiment, a sound through hole is formed in a side wall of the first recess, and the resonant cavity is communicated with the front resonant cavity through the sound through hole.

In one embodiment, a fourth recess and a fifth recess isolated by a cavity wall of the third recess are formed around the first recess except for the other three sides of the sound outlet hole side.

In a specific embodiment, on a side of the front cover plate facing away from the speaker body, the third recess is opened on a side of the first recess away from the sound outlet.

In a specific embodiment, on a side of the front cover plate facing away from the speaker body, the third recess is opened on any one of two sides of the first recess parallel to the sound outlet hole direction.

In one specific embodiment, the front cover forms a step portion on a side of the sound outlet hole facing the speaker body, and the sound outlet hole is opened on the step portion.

In one embodiment, a porous material is disposed within the resonant cavity.

In addition, in order to solve the above technical problem, the present application further provides a speaker box for an electronic device, where the speaker box includes a speaker body, a front cover plate, and a rear cover plate; the front cover plate and the loudspeaker body enclose a front sound cavity which influences a high-frequency resonance point of the loudspeaker body, and the rear cover plate and the loudspeaker body enclose a rear sound cavity which influences a low-frequency resonance point of the loudspeaker body; the front cover plate is provided with a sound outlet hole communicated with the front sound cavity;

the front cover plate is provided with a resonant cavity which is communicated with the front sound cavity.

The technical effects of the embodiments of the present application are described below:

in one embodiment, the present application provides a mobile phone, where the speaker box includes a speaker body, a front cover plate, and a back cover plate; the front cover plate and the loudspeaker body enclose a front sound cavity which influences a high-frequency resonance point of the loudspeaker body, and the rear cover plate and the loudspeaker body enclose a rear sound cavity which influences a low-frequency resonance point of the loudspeaker body; the front cover plate is provided with a sound outlet hole communicated with the front sound cavity.

The common loudspeaker box structure comprises a front cover plate, a loudspeaker body, an FPC (flexible printed circuit) or a welding wire and a rear cover plate, wherein a space between the rear cover plate and the loudspeaker body is a rear sound cavity and mainly determines a low-frequency resonance point of the loudspeaker; the part between the front cover plate and the loudspeaker body is a front sound cavity and radiates outwards through the sound outlet hole, and the part mainly determines the high-frequency resonance point of the loudspeaker.

In the prior art, due to the limitation of design structure, the front sound cavity of the speaker is generally a long and narrow structure, the resonance frequency of the front sound cavity is generally within the range of 3000-7000 Hz, the range is the high-frequency part of human ear hearing and is the normal working frequency range of the speaker, and due to the existence of the resonance, the mobile phone speaker has a peak within the range of 3000-7000 Hz. The sensitivity of the peak is more than ten and more dB higher than that of other frequency bands, so that the sensitivity of each frequency band which does not meet the requirement of transmission distortion-free is the same, and the high frequency of the mobile phone loudspeaker is sharp. Meanwhile, the higher harmonics generated by the vibration of other frequencies will be amplified by the peak to cause noise.

On the basis of the technical scheme, a resonant cavity is further formed in the front cover plate around the front sound cavity and is communicated with the front sound cavity.

In the above embodiment, the closed front resonant cavity is equivalent to increase the front cavity, so that the high-frequency resonant frequency forms a resonant peak with a lower resonant frequency, for example, the original resonant frequency is 4KHz, a peak value of 3KHz is generated at present, and 12dB per frequency multiplication attenuation is generated after 3KHz, so that two curves are mutually superposed, and the high-frequency loudness after 3KHz is greatly reduced. Therefore, the structural design of the loudspeaker box can effectively improve the sensitivity of a high-frequency resonance point of the loudspeaker, change the resonance frequency and avoid generating sharp distortion and noise.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and those skilled in the art can also obtain other drawings according to the drawings without creative efforts.

Fig. 1 is a schematic structural diagram of a speaker box of a mobile phone according to an exemplary embodiment of the present application;

FIG. 2 is a cross-sectional view of the assembled loudspeaker enclosure of FIG. 1;

FIG. 3 is a cross-sectional view of a speaker box of a handset according to another exemplary embodiment of the present application;

FIG. 4 is a top view of the speaker cabinet of FIG. 3 with the back cover removed;

FIG. 5 is a schematic diagram of the front cover plate of the speaker box of FIG. 3;

FIG. 6 is a schematic diagram of a comparison of frequency response curves of a speaker box of the prior art and a speaker box of the present application;

fig. 7 is a diagram comparing distortion curves of a speaker box in the prior art and a speaker box in the present application.

Wherein the correspondence between the names of the components and the reference numerals in figures 1 to 5 is:

a speaker body 100;

a front cover plate 200, a sound outlet hole 201, a first recess 202, a cover plate 203, a sound inlet hole 204, a fourth recess 205, a fifth recess 206, a step 207, and a third recess 208;

a rear cover plate 300;

a front sound chamber 400;

a rear sound chamber 500;

a resonant cavity 600;

foam 700;

FPC or wire bonds 800.

Detailed Description

In order to make the technical solutions of the present invention better understood, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention.

In some of the flows described in the present specification and claims and in the above figures, a number of operations are included that occur in a particular order, but it should be clearly understood that these operations may be performed out of order or in parallel as they occur herein, with the order of the operations being indicated as 101, 102, etc. merely to distinguish between the various operations, and the order of the operations by themselves does not represent any order of performance. Additionally, the flows may include more or fewer operations, and the operations may be performed sequentially or in parallel. It should be noted that, the descriptions of "first", "second", etc. in this document are used for distinguishing different messages, devices, modules, etc., and do not represent a sequential order, nor limit the types of "first" and "second" to be different.

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1 to 5, fig. 1 is a schematic structural diagram of a speaker box of a mobile phone according to an exemplary embodiment of the present application; FIG. 2 is a cross-sectional view of the assembled loudspeaker enclosure of FIG. 1; FIG. 3 is a cross-sectional view of a speaker box of a handset according to another exemplary embodiment of the present application; FIG. 4 is a top view of the speaker cabinet of FIG. 3 with the back cover removed; fig. 5 is a schematic structural view of a front cover plate of the speaker box of fig. 3.

In one embodiment, the mobile phone provided by the present application includes a speaker box, which includes a speaker body 100, a front cover 200 and a rear cover 300; the front cover 200 and the speaker body 100 enclose a front sound cavity 400 affecting the high-frequency resonance point of the speaker body 100, and the rear cover 300 and the speaker body 100 enclose a rear sound cavity 500 affecting the low-frequency resonance point of the speaker body 100; the front cover 200 is provided with a sound outlet hole 201 communicating with the front sound chamber 400.

As shown in fig. 1, a conventional speaker box structure includes a front cover 200, a speaker body 100, an FPC or a bonding wire 800, and a rear cover 300, as shown in fig. 2, wherein a space between the rear cover 300 and the speaker body 100 is a rear sound cavity 500, which mainly determines a low-frequency resonance point of the speaker; the front sound cavity 400 is located between the front cover 200 and the speaker body 100 and radiates outwards through the sound outlet hole 201, and this part mainly determines the high-frequency resonance point of the speaker.

In the prior art, due to the limitation of design structure, the front sound cavity 400 of the speaker is generally a long and narrow structure as shown in fig. 2, the resonance frequency of the front sound cavity is generally within the range of 3000 to 7000Hz, which is the high frequency part of human ear hearing and is the normal working frequency band of the speaker, and due to the existence of the resonance, the mobile phone speaker has a peak within the range of 3000 to 7000 Hz. The sensitivity of the peak is more than ten and more dB higher than that of other frequency bands, so that the sensitivity of each frequency band which does not meet the requirement of transmission distortion-free is the same, and the high frequency of the mobile phone loudspeaker is sharp. Meanwhile, the higher harmonics generated by the vibration of other frequencies will be amplified by the peak to cause noise.

On the basis of the above technical scheme, the front cover plate 200 around the front sound cavity 400 is further provided with a resonant cavity 600, and the resonant cavity 600 is communicated with the front sound cavity 400.

In the above embodiment, the closed front resonant cavity 600 is equivalent to increasing the front cavity, so that the high-frequency resonant frequency forms a resonant peak with a lower resonant frequency, for example, the original resonant frequency is 4KHz, a peak value of 3KHz is generated at present, and 12dB per frequency multiplication attenuation after 3KHz is generated, so that the two curves are mutually superimposed, and the high-frequency loudness after 3KHz is greatly reduced. Therefore, the structural design of the loudspeaker box can effectively improve the sensitivity of a high-frequency resonance point of the loudspeaker, change the resonance frequency and avoid generating sharp distortion and noise.

In some embodiments, as shown in fig. 5, a first recess 202 is opened on a side of the front cover 200 facing the speaker body 100, and as shown in fig. 3, the speaker body 100 covers the first recess 202 to form a front sound cavity 400; as shown in fig. 3, the resonant cavity 600 is opened on three sides except the sound outlet hole 201 side around the first recess 202. The resonant cavity 600 is arranged at the position, so that the position is convenient and the processing is easy.

Specifically, as shown in fig. 5, a third recessed portion 208 is formed on a side of the front cover 200 facing away from the speaker body 100, the cover 300 is covered on the third recessed portion 208, and the cover 300 and the third recessed portion 208 enclose a resonant cavity 600. It should be noted that, in fig. 5, due to the perspective, the outer wall of the third recess 208 is only seen, i.e. the outer wall of the third recess 208 is seen from the outside to the inside in the direction perpendicular to the paper surface. Assuming we look from inside to outside along the paper, we see the inner wall of the third recess 208. On this basis, as shown in fig. 3, the speaker box further includes a cover plate covering the third recess 208 so as to enclose a resonant cavity 600 with the third recess 208.

In the above technical solution, a recessed portion is formed on a side of the front cover plate 200 facing away from the speaker body 100, and then the cover plate is closed, so that the closed resonant cavity 600 is easily designed.

On the basis of the above embodiment, as shown in fig. 3 and fig. 5, the side wall of the first recess 202 is provided with the sound through hole 204, and the resonant cavity 600 is communicated with the front resonant cavity 400 through the sound through hole 204. In this kind of structure, through this logical sound hole 204 for preceding sound chamber 400 and resonant cavity 600 communicate, thereby has increased preceding sound chamber 400 in other words, make high frequency resonance frequency form a resonance peak that resonant frequency is lower, if former resonant frequency is 4KHz, produce a peak value of 3KHz now, have 12dB per doubling of frequency decay behind 3KHz, thereby make two curves superpose each other, reduce high frequency loudness behind 3KHz by a wide margin.

In some embodiments, further design of the location of the resonant cavity 600 may be made. For example, as shown in fig. 5, a fourth recess 205 and a fifth recess 206 isolated by the cavity wall of the third recess 208 are formed on the three sides of the first recess 202 excluding the sound outlet port 201 side.

On the basis of the above structure, in one embodiment, as shown in fig. 3 and 5, on the side of the front cover 200 facing away from the speaker body 100, the third recess 208 is opened on the side of the first recess 202 away from the sound outlet hole 201.

In addition to the above structure, in another embodiment, on the side of the front cover 200 facing away from the speaker body 100, the third recess 208 is opened on any one of two sides of the first recess 202 parallel to the sound outlet hole 201. That is, the resonant cavity 600 is opened at the corresponding positions of the fourth recess 205 and the fifth recess 206 in fig. 5.

Of course, the fourth recess 205 and the fifth recess 206 are opened on the side of the front cover 200 facing the speaker body 100. When the resonant cavities 600 are opened at these two positions, it is necessary to open the front cover 200 on the side facing away from the speaker body 100.

In the above-described embodiment, a further improved design can be made. For example, as shown in fig. 3 and 5, the front cover 200 has a step 207 formed on the sound outlet hole 201 side toward the speaker body 100, and the sound outlet hole 201 is opened in the step 207. In this structure, a design of a step portion 207 is formed on the front cover 200, and the sound hole 201 can be very conveniently opened.

In addition, in any of the above embodiments, further designs may be made. For example, a porous material is further disposed in the resonant cavity 600. For example, the porous material may be foam 700, but may also be other types of porous materials, which is not limited in this application.

In the description of the foregoing embodiment, due to the existence of the front resonant cavity 600, but standing waves may occur due to acoustic reflection in the front resonant cavity 600, as shown in fig. 3, the foam 700 is added in the front resonant cavity 600, the foam 700 is a porous foam material, and holes may pass through air, and after sound enters the rear front resonant cavity 600, sound is diffused and passed through the aperture of the foam 700, and then no longer reflected directly by a smooth cavity wall, so as to eliminate the cavity standing waves formed due to acoustic reflection, so that the flatness of frequency response and high frequency is obviously improved, and the distortion problem caused by the high frequency resonance point is also eliminated.

It should be noted that, as shown in fig. 3, the material in the front resonant cavity 600 is not limited to the foam 700, and other porous materials are feasible as long as the material and the processing method can reduce the standing wave of the cavity, and the material can diffuse the sound flow to prevent the standing wave formed by the superposition of the sound waves caused by the direct reflection of the cavity wall.

Referring to fig. 6 and 7, fig. 6 is a schematic diagram illustrating a comparison of frequency response curves of a speaker box in the prior art and a speaker box in the present application; fig. 7 is a diagram comparing distortion curves of a speaker box in the prior art and a speaker box in the present application.

It should be noted that the technical effects of the prior art are marked in fig. 6 and 7; one embodiment of the present application is designed for embodiments with a resonant cavity 600; another embodiment of the present application is an embodiment with a resonant cavity 600 and a foam 700 disposed in the resonant cavity 600.

In the prior art, due to design structure limitations, the front sound cavity 400 of the speaker is generally a long and narrow structure as shown in fig. 2, and the resonance frequency thereof is generally within the range of 3000 to 7000Hz, as shown in fig. 6; meanwhile, higher harmonics generated by vibrations of other frequencies are also amplified by the peak to cause noise, as shown in fig. 7, the conventional speaker box of a mobile phone distorts the peak at 4000 Hz.

In the present application, the closed front resonant cavity 600 is equivalent to increasing the front cavity, so that the high-frequency resonant frequency forms a resonant peak with a lower resonant frequency, for example, the original resonant frequency is 4KHz, a peak value of 3KHz is generated at present, and 12dB per frequency multiplication attenuation after 3KHz (as shown in fig. 6, the peak value of the common mobile phone speaker box is 4000 Hz), so that the two curves are mutually overlapped, and the high-frequency loudness after 3KHz is greatly reduced. Therefore, the structural design of the loudspeaker box can effectively improve the sensitivity of a high-frequency resonance point of the loudspeaker, change the resonance frequency and avoid generating sharp distortion and noise.

When the foam 700 is added in the resonant cavity 600, the cavity standing wave formed by sound reflection is eliminated, so that the flatness of frequency response and high frequency is obviously improved, and the distortion problem caused by high frequency resonance points is also eliminated. Finally, the optimized frequency response and distortion effect of the patent in fig. 6 and 7 is achieved.

Finally, the present application also provides a speaker box for an electronic device, the speaker box includes a speaker body 100, a front cover 200 and a rear cover 300; the front cover 200 and the speaker body 100 enclose a front sound cavity 400 affecting the high-frequency resonance point of the speaker body 100, and the rear cover 300 and the speaker body 100 enclose a rear sound cavity 500 affecting the low-frequency resonance point of the speaker body 100; the front cover 200 is provided with a sound outlet hole 201 communicating with the front sound chamber 400.

It should be noted that the electronic device may be a mobile phone, and may also be a mobile or non-mobile terminal, including a watch, a pad, and the like, which is not limited in this application. The technical effect of the speaker box for the electronic device is the same as that of the speaker box of the mobile phone in the above embodiment, and is not described herein again.

The above-described embodiments of the apparatus are merely illustrative, and the units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of the present embodiment. One of ordinary skill in the art can understand and implement it without inventive effort.

Reference throughout this specification to "embodiments," "some embodiments," "one embodiment," or "an embodiment," etc., means that a particular feature, component, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, appearances of the phrases "in various embodiments," "in some embodiments," "in at least one other embodiment," or "in an embodiment," or the like, throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, components, or characteristics may be combined in any suitable manner in one or more embodiments. Thus, without limitation, a particular feature, component, or characteristic illustrated or described in connection with one embodiment may be combined, in whole or in part, with a feature, component, or characteristic of one or more other embodiments. Such modifications and variations are intended to be included within the scope of the present application.

Moreover, those skilled in the art will appreciate that aspects of the present application may be illustrated and described in terms of several patentable species or situations, including any new and useful combination of processes, machines, manufacture, or materials, or any new and useful improvement thereon. Accordingly, various aspects of the present application may be embodied entirely in hardware, entirely in software (including firmware, resident software, micro-code, etc.) or in a combination of hardware and software. The above hardware or software may be referred to as "data block," module, "" engine, "" terminal, "" component, "or" system. Furthermore, aspects of the present application may be represented as a computer product, including computer readable program code, embodied in one or more computer readable media.

It is to be noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that an article or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

The above description is merely exemplary of the present application and is presented to enable those skilled in the art to understand and practice the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the application. Thus, the present application is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.

Claims

1. A mobile phone is characterized by comprising a loudspeaker box, wherein the loudspeaker box comprises a loudspeaker body, a front cover plate and a rear cover plate; the front cover plate and the loudspeaker body enclose a front sound cavity which influences a high-frequency resonance point of the loudspeaker body, and the rear cover plate and the loudspeaker body enclose a rear sound cavity which influences a low-frequency resonance point of the loudspeaker body; the front cover plate is provided with a sound outlet hole communicated with the front sound cavity;

2. The mobile phone of claim 1, wherein a first recess is formed in a side of the front cover plate facing the speaker body, and the speaker body covers the first recess to form the front sound cavity; the resonant cavity is arranged on the periphery of the first concave part except the other three sides on one side of the sound outlet hole.

3. The mobile phone according to claim 2, wherein a third recess is formed in a side of the front cover plate facing away from the speaker body, and the cover plate covers the third recess, and the cover plate and the third recess enclose the resonant cavity.

4. The mobile phone of claim 3, wherein a sound hole is formed on a sidewall of the first recess, and the resonant cavity is connected to the front cavity through the sound hole.

5. The cellular phone according to claim 3 or 4, wherein a fourth recess and a fifth recess isolated by a cavity wall of the third recess are formed around the first recess except for the other three sides of one side of the sound outlet hole.

6. The mobile phone according to claim 5, wherein the third recess is formed on a side of the first recess away from the sound outlet on a side of the front cover facing away from the speaker body.

7. The mobile phone according to claim 5, wherein the third recess is formed on either one of two sides of the first recess parallel to the sound outlet hole on a side of the front cover facing away from the speaker body.

8. The cellular phone according to any one of claims 1 to 4, wherein said front cover has a stepped portion formed on a side of said sound emission hole facing said speaker body, and said sound emission hole is opened in said stepped portion.

9. A handset as claimed in any one of claims 1 to 4, wherein the resonant cavity is provided with a porous material.

10. A speaker box for an electronic device, the speaker box comprising a speaker body, a front cover plate and a back cover plate; the front cover plate and the loudspeaker body enclose a front sound cavity which influences a high-frequency resonance point of the loudspeaker body, and the rear cover plate and the loudspeaker body enclose a rear sound cavity which influences a low-frequency resonance point of the loudspeaker body; the front cover plate is provided with a sound outlet hole communicated with the front sound cavity;