Earphone microphone

1. An earphone microphone comprising a speaker, a microphone having first and second sound input holes, a case, a seal member for sealing between the case and an external acoustic meatus when the earphone microphone is inserted in the external acoustic meatus, wherein

the case comprises:

an acoustic space,

a first opening which faces the external acoustic meatus, and

a second opening which faces outside the casing except the external acoustic meatus,

the acoustic space is divided into a first acoustic space and a second acoustic space, the second acoustic space having a volume smaller than a volume of the first acoustic space,

the first acoustic space communicates with the first opening, and the speaker is arranged in the first acoustic space, and

the second acoustic space communicates with the first and second openings, and the microphone is arranged in the second acoustic space, and

the first and second sound input holes face the second acoustic space.

2. An earphone microphone according to claim 1 , wherein the case has a partition wall that separates the first and second acoustic spaces from each other.

3. An earphone microphone according to claim 1 , further comprising a controller configured to generate a sound signal based on an output signal of the microphone, wherein

the microphone includes a first microphone having the first sound input hole and a second microphone having the second sound input hole.

4. An earphone microphone according to claim 1 , further comprising a signal wire for transmitting an output signal of the microphone, and a sheath member for covering the signal wire extending from the case, wherein

the second opening communicates with outside the case through a gap between the sheath member and the signal wire.

5. An earphone microphone according to claim 1 , wherein the sheath member has an opening that faces outside the case and communicates with the second opening.

6. An earphone microphone according to claim 4 , wherein

the first opening comprises a plurality of first openings, and

the first acoustic space communicates with a part of the plurality of first openings, and the second acoustic space communicates with another part of the plurality of first openings.

7. An earphone microphone comprising a microphone, a case, and a seal member for sealing between the case and an external acoustic meatus when the earphone microphone is inserted into the external acoustic meatus, wherein,

the case has formed therein:

a plurality of first openings that face the external acoustic meatus,

a second opening that faces outside the casing except the external acoustic meatus,

a first acoustic space that communicates with a part of the plurality of first openings and in which the speaker is arranged, and

a second acoustic space that communicates with another part of the plurality of first openings and with the second opening and in which the microphone is arranged, and

the case has a partition wall that separates the first and second acoustic spaces from each other.

8. An earphone microphone according to claim 7 , wherein the microphone is a differential microphone having a first sound input hole and a second sound input hole.

9. An earphone microphone according to claim 7 , further comprising a controller configured to generate a sound signal based on an output signal of the microphone, wherein

the microphone includes a first microphone having a first sound input hole and a second microphone having a second sound input hole.

10. An earphone microphone according to claim 7 , further comprising a signal wire for transmitting an output signal of the microphone, and a sheath member for covering the signal wire extending from the case, wherein

the second opening communicates with outside the case through a gap between the sheath member and the signal wire.

11. An earphone microphone according to claim 10 , wherein the sheath member has an opening that faces outside the case and communicates with the second opening.

12. An earphone microphone comprising a microphone, a case, a seal member for sealing between the case and an external acoustic meatus when the earphone microphone is inserted in the external acoustic meatus, a signal wire for transmitting an output signal of the microphone, and a sheath member for covering the signal wire extending from the case, wherein,

the case has formed therein

a first opening that faces the external acoustic meatus,

a second opening that faces outside the casing except the external acoustic meatus, and

an acoustic space that communicates with the first and second openings and in which the speaker and the microphone are arranged,

the sheath member has an opening that faces outside the case and communicates with the second opening, and

the second opening communicates with outside the case through a gap between the sheath member and the signal wire.

13. An earphone microphone according to claim 12 , wherein the microphone is a differential microphone having a first sound input hole and a second sound input hole.

14. An earphone microphone according to claim 12 , further comprising a controller configured to generate a sound signal based on an output signal of the microphone, wherein

the microphone includes a first microphone having a first sound input hole and a second microphone having a second sound input hole.