EP3264791A1

EP3264791A1 - Earphone

Info

Publication number: EP3264791A1
Application number: EP17176430.1A
Authority: EP
Inventors: Masanori Ito
Original assignee: Onkyo Corp
Current assignee: Onkyo Corp
Priority date: 2016-06-27
Filing date: 2017-06-16
Publication date: 2018-01-03
Anticipated expiration: 2037-06-16
Also published as: JP2018006784A; JP6754075B2; EP3264791B1

Abstract

The present invention relates to a canal earphone configured such that a reproduced sound wave outlet is inserted into an ear canal inlet of a user.

In the earphone, the housing 2 includes a nozzle portion forming a first acoustic path communicating with a first acoustic space to guide a sound wave to the ear canal of the user, and a leak port portion forming a second acoustic path communicating with a second acoustic space to guide the sound wave to an external space; and the leak port portion 7 includes a tubular member forming the second acoustic path and exhibiting flexibility, and a fixing portion configured to fix, without bending of the tubular member, the tubular member along an inner wall portion or an outer wall portion of the housing forming the second acoustic space.

Description

BACKGROUND OF THE INVENTION

1. FIELD OF THE INVENTION

The present invention relates to an earphone attached to a user's ear to reproduce sound, and specifically relates to an earphone configured such that a reproduced sound wave outlet is inserted into an ear canal inlet of a user.

2. DESCRIPTION OF THE RELATED ART

Headphones and earphones are each configured to apply an audio signal to a speaker unit closely disposed in contact with a user's ear, thereby reproducing sound. There are various forms of the earphone attached to the user's ear.
For example, the earphones include an earphone having a relatively-large speaker unit as in a headphone and having an ear hook portion configured to attach and place a main unit onto the ear pinna. Moreover, there is an inner ear type earphone used such that a main unit is attached and accommodated on the inside of the ear pinna and that sound is emitted from a sound emission surface of the main unit to the ear canal. In addition, a so-called canal earphone has become widespread, which is used such that a main unit is attached and accommodated on the inside of the ear pinna and that a sound cylinder portion protruding from the main unit is, together with an earpiece attached to the sound cylinder portion, inserted into the ear canal.
A smaller speaker unit results in a higher sound pressure level and more difficulty in sufficient expansion of a sound reproduction frequency band for ensuring a favorable reproduced sound quality. Similar problems are also caused for the speaker unit of the inner ear type earphone or the canal earphone attached to the user's ear. Specifically, in the canal earphone configured such that a reproduced sound wave outlet is inserted into an ear canal inlet of a user, there are the following problems: a housing to which the speaker unit is attached is small; it is difficult to employ the speaker unit having a necessary and sufficient sound reproduction capacity and having a large diaphragm diameter; and the canal earphone is susceptive to influence of the structure of the housing.
JP-UM-A-63-95388 or JP-A-2015-195444 describes a case where an opening, a hole, an acoustic path, a leak port, etc. for communication between an internal space and an external space of a housing of a typical earphone are provided. Specifically, the earphone is disclosed, which is provided with a relatively-long acoustic path communicating from the internal space of the housing on a back side of a speaker unit to the external space of the housing.
Moreover, Japanese Patent No. 5696249 discloses a typical canal earphone including a housing having an acoustic space on the inside and provided with a tubular sound guide portion protruding from a front surface of the housing, an ear pad attached to the sound guide portion and inserted into the ear canal, a frame provided with a first air hole and provided in the housing to divide the acoustic space into a first acoustic space and a second acoustic space, an electricity/sound wave conversion portion configured to covert an electric signal into a first sound wave to output the first sound wave to the sound guide portion, and a sound pressure adjustment portion attached to the frame. The sound pressure adjustment portion includes a third acoustic space communicating with the first air hole, a tubular second air hole communicating with the second and third acoustic spaces, and a first acoustic resistor inserted into the second air hole and configured to reduce a sound pressure with a predetermined frequency band by adjustment of such an insertion position.
Note that further modification of the typical earphone has been demanded. Specifically, in the canal earphone configured such that the reproduced sound wave outlet is inserted into the ear canal inlet of the user, the structure of the housing forming the extremely-small internal space influences sound pressure frequency properties of a reproduced sound wave. For this reason, as long as the user does not hear clear reproduced sound, it is difficult to realize natural preferable sound reproduction.

SUMMARY OF THE INVENTION

The present invention has been made to solve the above-described problems of the typical technology. An object of the present invention relates to a canal earphone configured such that a reproduced sound wave outlet is inserted into an ear canal inlet of a user, and is to provide an earphone including a housing so that proper sound pressure frequency properties are provided in a case where a speaker unit is attached, thereby realizing clear preferable sound reproduction.
The earphone of the present invention is an earphone including a speaker unit configured to electroacoustically transduce an audio signal into a sound wave, and a housing configured to define first and second acoustic spaces on one and the other sides of a diaphragm of the speaker unit, the speaker unit being attached to the inside of the housing. The housing includes a nozzle portion forming a first acoustic path communicating with the first acoustic space to guide the sound wave to an ear canal of a user, and a leak port portion forming a second acoustic path communicating with the second acoustic space to guide the sound wave to an external space. The leak port portion includes a tubular member forming the second acoustic path and exhibiting flexibility, and a fixing portion configured to fix, without bending of the tubular member, the tubular member along an inner wall portion or an outer wall portion of the housing forming the second acoustic space.
Preferably, in the earphone of the present invention, the leak port portion is configured such that the tubular member is winded in a spiral shape to form the second acoustic path.
Preferably, in the earphone of the present invention, the fixing portion of the leak port portion includes a groove or a cover member provided at the inner wall portion and/or the outer wall portion of the housing forming the second acoustic space and configured to house the tubular member.
Preferably, in the earphone of the present invention, the second acoustic path of the leak port portion is formed such that the opening area of an opening end portion communicating with the second acoustic space or the external space is larger than the sectional area of a middle portion.
Preferably, in the earphone of the present invention, the tubular member of the leak port portion further includes, at the opening end portion communicating with the second acoustic space or the external space, a protection member exhibiting air permeability.
Preferably, in the earphone of the present invention, the housing further includes a cord connection portion configured to connect a cord to the speaker unit, the audio signal being supplied via the cord.
Preferably, in the earphone of the present invention, the housing further includes, at a tip end of the nozzle portion, an earpiece attachment portion to which an earpiece is attached, the earpiece being to be inserted into the ear canal of the user, and the earphone further includes the earpiece attached to the earpiece attachment portion.
Hereinafter, features of the present invention will be described.
The earphone of the present invention includes the speaker unit configured to electroacoustically transduce the audio signal into the sound wave, and the housing configured to define the first and second acoustic spaces on one and the other sides of the diaphragm of the speaker unit, the speaker unit being attached to the inside of the housing. The housing includes the nozzle portion forming the first acoustic path communicating with the first acoustic space to guide the sound wave to the ear canal of the user. Thus, the canal earphone can be realized such that the earpiece closely contacts the ear canal as long as the housing further includes the cord connection portion configured to connect the cord configured to supply the audio signal to the speaker unit and the nozzle portion of the housing further includes the earpiece attachment portion to which the earpiece to be inserted into the ear canal of the user is attached.
Such an earphone housing includes the leak port portion forming the second acoustic path communicating with the second acoustic space to guide the sound wave to the external space. The leak port portion includes the tubular member forming the second acoustic path and exhibiting flexibility, and the fixing portion configured to fix, without bending the tubular member, the tubular member along the inner wall portion or the outer wall portion of the housing forming the second acoustic space. Since the tubular member as a hollow tubular member exhibits flexibility, the fixing portion forms the tubular member into a predetermined shape, and fixes the tubular member to the housing.
Thus, even in a case where the second acoustic path needs to be formed to have thin long dimensions to ensure proper sound pressure frequency properties in the canal earphone, the tubular member exhibiting flexibility is fixed along the housing, and therefore, the size of the entirety of the housing can be reduced without great protrusion of the leak port portion from the housing. As a result, natural preferable sound reproduction can be realized.
Preferably, in the earphone of the present invention, the leak port portion of the housing is configured such that the tubular member is winded in the spiral shape to form the second acoustic path. In the case of winding the tubular member in the spiral shape, the second acoustic path having greater dimensions than those corresponding to at least the circumferential length of the substantially circular housing can be formed. This leads to an advantage that a resonant frequency can be adjusted even in a relatively-low frequency band, and therefore, a sound reproduction frequency band can be sufficiently expanded for ensuring a favorable reproduced sound quality.
Moreover, in the earphone of the present invention, the fixing portion of the leak port portion preferably includes the groove or the cover member provided at the inner wall portion and/or the outer wall portion of the housing forming the second acoustic space and configured to house the tubular member. With the fixing portion provided with the tubular member insertion grooves at the inner wall portion and the outer wall portion of the housing or the fixing portion configured to fix the tubular member with the cover member, the tubular member can be, without bending, formed in a predetermined substantially-arc shape, and can be fixed to the housing. As a result, defects such as closing or narrowing of the second acoustic path at a bent portion of the tubular member forming the leak port portion can be prevented. In a case where the tubular member is, with the cover member, fixed to the outer wall portion of the housing, designability can be provided to the cover member, and the earphone with significantly beautiful appearance can be realized.
Further, the second acoustic path of the leak port portion may be formed such that the opening area of the opening end portion communicating with the second acoustic space or the external space is larger than the sectional area of the middle portion. For example, the opening end portion of the tubular member forming the leak port portion is diagonally cut to have an oval opening so that the opening area thereof can be larger than the sectional area of the middle portion. Consequently, operation and effects of the leak port can be enhanced. In a case where the tubular member of the leak port portion further includes, at the opening end portion communicating with the second acoustic space or the external space, the protection member exhibiting air permeability, defects such as closing or narrowing of the second acoustic path due to entrance of a foreign substance into the tubular member through the opening end portion can be prevented.
The earphone of the present invention includes the housing having the leak port portion so that proper sound pressure frequency properties are provided in a case where the speaker unit is attached, and therefore, the canal earphone realizing clear preferable sound reproduction can be provided.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is a view for describing an earphone of a preferred embodiment of the present invention;
Fig.2 (includes 2(a) to 2(c)) are views for describing an internal structure of the earphone of the preferred embodiment; and
Fig. 3 is a graph for describing sound pressure frequency properties of the earphone of the preferred embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Hereinafter, an earphone of a preferred embodiment of the present invention will be described. However, the present invention is not limited to such an embodiment.
Fig. 1 and Fig. 2 (includes 2(a) to 2(c)) are views for describing an earphone 1 of the preferred embodiment of the present invention. Specifically, Fig. 1 illustrates a perspective view of the earphone 1 attached to one ear of a user. Fig. 1 illustrates a state in which a cover 8 is detached, the cover 8 being to be fixed to a housing member 12 to cover part of a later-described leak port 7.
Moreover, Figs. 2(a) to 2(c) are sectional views for describing an internal structure of the earphone 1. Fig. 2(a) is a sectional view along a section A-A' of Fig. 1, Fig. 2(b) is a structural view corresponding to a section B-B' of Fig. 2(a) and illustrating only the leak port 7, and Fig. 2(c) is a C-C' sectional view of the leak port 7 corresponding to Fig. 2(b). Note that the other structures of the earphone 1 not necessarily described regarding to the present invention will not be shown in the figures, and will not be described later.
The earphone 1 of the present embodiment is a canal earphone configured such that a reproduced sound wave outlet is inserted into an ear canal hole of the ear pinna of the user. The earphone 1 includes, for stereo reproduction, substantially symmetrical earphones attached respectively to the right and left ears of the user. The structure of the earphone 1 corresponding to one ear will be described below. Needless to say, the form of the earphone 1 is not limited to the case of the present embodiment.
The earphone 1 is configured such that a speaker unit 3 configured to receive an audio signal supplied via a cord 5 to reproduce sound is attached to a housing 2 of the earphone 1. The speaker unit 3 is an electrodynamic electroacoustic transducer including a magnetic circuit with a magnetic gap and configured to vibrate a diaphragm coupled to a voice coil inserted into the magnetic gap, the audio signal being supplied to the voice coil. The speaker unit 3 emits sound waves to front and back sides of the (not-shown) diaphragm, the sound waves being in an opposite phase relationship. Thus, the housing 2 needs to be attached to the speaker unit 3 such that one side of the diaphragm of the speaker unit 3 is separated from the other side.
The housing 2 of the present embodiment can be attached to the speaker unit 3 having a diameter corresponding to the size of the ear canal hole of the ear pinna of the user. The housing 2 includes a substantially cylindrical base member 11 having a nozzle portion, and the housing member 12 coupled to a back side of the base member 11 to form a cavity. The base member 11 and the housing member 12 of the housing 2 define an acoustic space 17 on the front side of the diaphragm of the speaker unit 3, and form an acoustic space 18 separated from the acoustic space 17 on the back side on which the magnetic circuit of the speaker unit 3 is present.
The base member 11 is made of a metal material or a resin material, and includes a speaker unit attachment portion at which the speaker unit 3 is attached to an inner wall portion. An outer-diameter frame of the speaker unit 3 has outer dimensions substantially matching with the inner-diameter dimensions of the speaker unit attachment portion of the substantially cylindrical base member 11. The base member 11 includes the nozzle portion formed thinner on a tip end side than the speaker unit attachment portion such that the base member 11 is inserted into the ear canal hole of the ear pinna of the user. The nozzle portion forms, on the inside thereof, an acoustic path communicating with the acoustic space 17 to guide a sound wave to the ear cannel of the user.
An earpiece attachment portion to which an earpiece 6 is attached is formed on an outer peripheral surface of the nozzle portion of the base member 11. With attachment of the shade-shaped earpiece 6 exhibiting elasticity, the canal earphone can be realized such that the earpiece 6 closely contacts the ear canal hole. The earpiece 6 allows the user to stably attach the earphone 1 to the ear pinna. Note that a protection net 14 as a protection member exhibiting air permeability is attached to an opening end portion of the nozzle portion. The protection net 14 prevents defects such as closing of the acoustic path due to entrance of a foreign substance into the nozzle portion through the opening end portion thereof. Moreover, the base member 11 may be provided with a (not-shown) leak hole or port communicating with the acoustic space 17 to guide a sound wave to an external space.
Meanwhile, the housing member 12 is made of a metal material or a resin material, and a cord bush 4 configured to fix the cord 5 is coupled to the housing member 12, the audio signal being supplied to the speaker unit 3 through the cord 5. The cord bush 4 is made of a soft rubber material to contain the cord 5, and one side of the cord bush 4 is attached to an attachment hole of the housing member 12. In the case of the earphone 1 configured such that a jack for plug connection is provided at the housing 2, the housing member 12 may include, as a cord connection portion for connecting the cord 5 configured to supply the audio signal to the speaker unit 3, a jack into which a plug at a tip end of the cord 5 is inserted, instead of the cord bush 4.
The housing member 12 defines the acoustic space 18 formed separately from the acoustic space 17, and includes the leak port 7 forming an acoustic path communicating with the acoustic space 18 to guide a sound wave to the external space. The leak port 7 uses, as a hollow tubular member exhibiting flexibility and made of silicon resin, a tube having an outer diameter of 2.0 mm, an inner diameter of 1.0 mm, and a length of about 40.0 mm, thereby forming the acoustic path. As illustrated in the figures, the leak port 7 is configured such that an opening end portion 7a communicating with the acoustic space 18 is disposed on the inside of the housing member 12 and that an opening end portion 7c communicating with the external space is disposed on the outside of the housing member 12.
The length and inner diameter of the tube of the leak port 7 are preferably adjusted according to the air chamber capacity of the acoustic space 18. Moreover, the leak port 7 may be a hollow tubular member having necessary inner-diameter dimensions and exhibiting flexibility, and the material of the leak port 7 is not limited to silicon resin. The leak port 7 may be made of other materials than silicon resin, such as a rubber-based material, an elastomer resin material, and a polyvinyl chloride (PVC) resin material.
That is, as illustrated in Fig. 2(b), the leak port 7 winded in a spiral shape passes through the hole of the housing member 12, and both ends of the leak port 7 are exposed on the inside and outside of the housing 2. The opening end portions 7a, 7c of the leak port 7 are, by diagonal cutting of the tubular member, formed such that the opening areas of the opening end portions 7a, 7c are larger than the sectional area of a middle portion 7b of the leak port 7. Note that a protection net 15 as a protection member exhibiting air permeability is attached to the opening end portion 7c of the leak port 7. The protection net 15 prevents defects such as closing of the acoustic path due to entrance of a foreign substance into the leak port 7 through the opening end portion thereof.
For providing proper sound pressure frequency properties, the leak port 7 as the acoustic path having thin long dimensions needs to be formed in the canal earphone 1. Since the leak port 7 is the extremely-thin long member as compared to the dimensions of the housing 2, a certain design needs to be made for attachment of the housing 2. For accommodating the long leak port 7 in the housing 2 as in the case of the present embodiment, it is necessary to form the leak port 7 in a predetermined shape without a bent portion. This is because the bent portion at which the tube is sharply bent leads to closing of the inside of the tubular member or extreme narrowing of the inner area of the tubular member, and therefore, the leak port 7 no longer functions as the acoustic path.
The housing member 12 includes a fixing portion 16 configured to fix, without bending of the leak port 7, the leak port 7 along inner and outer wall portions of the housing member 12 forming the acoustic space 18. A fixing portion 16a as a groove into which the leak port 7 is fitted is formed at the inner wall portion of the housing member 12. Similarly, a fixing portion 16b as a groove along which the leak port 7 extends is formed at the outer wall portion of the housing member 12. The fixing portion 16a and the fixing portion 16b are configured to communicate with each other through the hole penetrating the housing member 12. For fixing the leak port 7 to the fixing portion 16, a bonding material such as an adhesive or a double-sided tape may be used.
As illustrated in Fig. 1 and Figs. 2(a) to 2(c), the leak port 7 as the hollow tubular member exhibits flexibility. Thus, the leak port 7 is, without bending, formed in a predetermined substantially-arc shape by the fixing portion 16, and is fixed to the housing member 12. In parallel, one end side of the tubular leak port 7 is exposed at the outer wall portion of the housing member 12. Note that the leak port 7 is fixed along the housing member 12, and therefore, the size of the entirety of the housing 2 of the earphone 1 can be reduced without great protrusion of the leak port 7 from the housing 2.
The fixing portion 16 configured to fix the leak port 7 can be used not only as the groove for housing the tubular leak port 7, but also other fixing members can be used. In the case of the present embodiment, the cover 8 is further provided, which is attached to the outer wall portion of the housing member 12 to cover and fix the leak port 7 and is configured not to expose, to the external appearance, the hole portion through which the leak port 7 is exposed to the outside. Needless to say, the cover configured to cover and fix the leak port 7 may be provided at the outer wall portion of the housing member 12. Thus, designability can be provided to the cover 8, and the beauty of the external appearance of the earphone 1 can be improved.
Fig. 3 is a graph for describing sound pressure frequency properties of the earphone 1 of the present embodiment and an earphone 10 of a comparative example. The horizontal axis indicates the frequency of an input audio signal, and the vertical axis indicates a sound pressure level at the ear canal in the case of attaching the earphone 1 or the earphone 10 to an ear mold as a measurement tool. The (not-shown) earphone 10 of the comparative example is configured such that the housing 2 of the earphone 1 of the present embodiment does not include the leak port 7 forming the acoustic path communicating with the acoustic space 18 to guide a sound wave to the external space. The common speaker unit 3 is provided. Thus, Fig. 3 shows features and advantageous effects of the leak port 7 of the canal earphone 1.
As illustrated in Fig. 3, the sound pressure frequency properties of the earphone greatly vary according to the presence or absence of the leak port 7. As compared to the earphone 10 of the comparative example, the earphone 1 of the present embodiment is improved to exhibit approximately flat properties of about 300 Hz to 1 kHz. As a result, the articulation of reproduced sound can be improved. The canal earphone 1 configured such that the reproduced sound wave outlet is inserted into an inlet of the ear canal of the user can realize more natural preferable sound reproduction as compared to the earphone 10 of the comparative example.
In this example, the leak port 7 is preferably configured such that the thin tubular member is winded in the spiral shape to form the acoustic path. This is because it is suitable that the length dimension of the leak port 7 is greater than that corresponding to at least the circumferential length of the substantially circular housing 2. With shortening of the leak port 7, a sound pressure at around 300 Hz does not lower as in the above-described case of the present embodiment, leading to a lower reproduced sound articulation. For this reason, a reproduced sound quality is lowered.
Note that the leak port 7 configured such that the above-described thin tubular member is winded in the spiral shape to form the acoustic path is preferably provided in the canal earphone 1. However, similar advantageous effects cannot be, on the other hand, provided when the leak port 7 having a similar thickness/length is applied to other typical non-canal earphones. In this case, there are problems such as an increase in a low-pitched sound pressure level, a decrease in the articulation, and narrowing of a sound reproduction frequency band. As a result, it is difficult for these earphones to ensure a favorable reproduced sound quality.
For accommodating, in the housing 2, the relatively-longer leak port 7 than the size of the housing 2 of the earphone 1, the leak port 7 needs to be formed in a predetermined shape without the bent portion as in the present embodiment. In addition, the long tubular leak port 7 may be, as necessary, shaped in such a spiral shape that the leak port 7 is winded with at least one or more turns. Even in a case where the leak port 7 can be accommodated while being winded with equal to or less than one turn, when the fixing portion 16 is provided such that shaping of the leak port 7 is made by winding of the leak port 7 in the spiral shape, the leak port 7 can be fixed along the inner wall portion and/or the outer wall portion of the housing member 12 forming the acoustic space 18.
In a case where the leak port 7 is relatively short or the leak port 7 is shaped by winding of the leak port 7 in the spiral shape on the inside of the housing member 12, the length of a portion of the leak port 7 protruding to the outside of the housing member 12 is shortened. In the case of the shortest length, the opening end portion 7c of the leak port 7 on an external space side might be merely exposed at the outer wall portion of the housing member 12. For this reason, the fixing portion 16 of the housing member 12 may be provided at at least the inner wall portion of the housing member 12 such that the leak port 7 is, without bending, fixed along the inner wall portion of the housing member 12. Similarly, in the case where the leak port 7 is relatively short, the fixing portion 16 of the housing member 12 may be provided at the outer wall portion such that the leak port 7 is fixed along the outer wall portion of the housing member 12. That is, the fixing portion 16 of the housing member 12 may be provided at at least either one of the inner wall portion or the outer wall portion of the housing member 12, thereby fixing the leak port 7 along the housing member 12.
Note that the leak port 7 of the housing 2 does not necessarily use the soft tubular member to form the acoustic path communicating with the acoustic space 18 to guide a sound wave to the external space, but instead, a tubular portion having substantially the same sectional area may be provided to penetrate the outer and inner wall portions of the housing member 12. Alternatively, the acoustic path alternative to the leak port 7 may be provided using the cover 8 attached to the housing member 12. As another alternative, the entirety of the leak port 7 is not necessarily formed of the soft tubular member, but the above-described tubular portion penetrating the outer and inner wall portions of the housing member 12 may be used as a substitute for part of the leak port 7. With the long leak port 7, the sound reproduction frequency band can be sufficiently expanded, and a favorable reproduced sound quality can be ensured.
Moreover, operation and effects of the leak port can be enhanced as long as the opening areas of the opening end portions 7a, 7c of the leak port 7 are formed larger than that of the middle portion 7b by diagonal cutting of the tube or the tubular member. Thus, the leak port 7 may be formed in such a manner that tubular bodies with different thicknesses are coupled together.
Further, in the above-described embodiment, the leak port 7 includes, at the opening end portion 7c communicating with the external space, the protection net 15 exhibiting air permeability. However, the protection net 15 may be provided at the opening end portion 7a communicating with the acoustic space 18 of the leak port 7. Defects such as closing or narrowing of the leak port 7 due to entrance of a foreign substance into the leak port 7 can be prevented.
The earphone of the present invention is not limited to the canal earphone as illustrated in the figures, and may be an earphone further including another ear hook portion. Moreover, the present invention is not limited to the earphone, and overhead earphones may be configured such that earphones corresponding respectively to the right and left ears are coupled together through a headband. The earphone is not limited to stereo reproduction and multichannel surround reproduction for home use, and is also applicable to in-vehicle audio equipment and sound reproduction facilities such as movie theaters.

Claims

An earphone comprising:
a speaker unit configured to electroacoustically transduce an audio signal into a sound wave; and

a housing configured to define first and second acoustic spaces on one and the other sides of a diaphragm of the speaker unit, the speaker unit being attached to an inside of the housing,

wherein the housing includes
a nozzle portion forming a first acoustic path communicating with the first acoustic space to guide the sound wave to an ear canal of a user, and

a leak port portion forming a second acoustic path communicating with the second acoustic space to guide the sound wave to an external space, and

the leak port portion includes
a tubular member forming the second acoustic path and exhibiting flexibility, and

a fixing portion configured to fix, without bending of the tubular member, the tubular member along an inner wall portion or an outer wall portion of the housing forming the second acoustic space.
The earphone according to claim 1, wherein
the leak port portion is configured such that the tubular member is winded in a spiral shape to form the second acoustic path.
The earphone according to claim 1 or 2, wherein
the fixing portion of the leak port portion includes a groove or a cover member provided at the inner wall portion and/or the outer wall portion of the housing forming the second acoustic space and configured to house the tubular member.
The earphone according to any one of claims 1 to 3, wherein
the second acoustic path of the leak port portion is formed such that an opening area of an opening end portion communicating with the second acoustic space or the external space is larger than a sectional area of a middle portion.
The earphone according to any one of claims 1 to 4, wherein
the tubular member of the leak port portion further includes, at the opening end portion communicating with the second acoustic space or the external space, a protection member exhibiting air permeability.
The earphone according to any one of claims 1 to 5, where
the housing further includes a cord connection portion configured to connect a cord to the speaker unit, the audio signal being supplied via the cord.
The earphone according to any one of claims 1 to 6, wherein
the housing further includes, at a tip end of the nozzle portion, an earpiece attachment portion to which an earpiece is attached, the earpiece being to be inserted into the ear canal of the user, and

the earphone further includes the earpiece attached to the earpiece attachment portion.