Speaker system

1. A speaker system comprising:

a cabinet;

at least one speaker unit fixed to the cabinet;

a gas adsorbent which is situated inside the cabinet and which is made from a porous material; and

at least one drone cone fixed to the cabinet, wherein

the speaker unit includes moisture-proof component parts,

the drone cone includes at least one diaphragm comprising a moisture-impermeable member,

the diaphragm of the drone cone has provided therein a tubular structure which has a tubular hollow for allowing ventilation between an inside and an outside of the cabinet, and

a resonant frequency which is determined by an acoustic impedance of the tubular structure and an acoustic impedance of the cabinet is lower than a minimum resonant frequency of an acoustic impedance of the speaker system.

2. The speaker system according to, claim 1 , wherein

the drone cone includes:

a first diaphragm which is made from a moisture-impermeable material, and which has a first through-hole;

an edge which is made from a moisture-impermeable material, which has a second through-hole having narrow openings, and which is fixed to the first diaphragm such that the first through-hole is connected to one extremity of the second through-hole and covers one of the openings of the second through-hole; and

a second diaphragm which is made from a moisture-impermeable material, which has a third through-hole, and which is fixed to the edge such that the third through-hole is connected to another extremity of the second through-hole and covers another of the openings of the second through-hole, and

the tubular hollow is formed by the first, second, and third through-holes.

3. The speaker system according to claim 1 , further comprising a moisture absorbent material which is provided in a vicinity of the tubular hollow so as to absorb moisture.

4. The speaker system according to claim 1 , wherein

the cabinet includes a divider for dividing an internal cavity of the cabinet into a first cavity and a second cavity,

the drone cone is fixed to the divider,

the cabinet includes a port for acoustically connecting the first cavity to the outside of the cabinet,

the speaker unit is fixed to the cabinet such that the speaker unit at least partially located within the first cavity,

the gas adsorbent is situated inside the second cavity, and

the tubular structure has the tubular hollow for allowing ventilation between the second cavity and the outside of the cabinet.

5. A portable terminal apparatus comprising:

the speaker system according to claim 1 ; and

a housing accommodating the speaker system thereinside.

6. An audio-visual apparatus comprising:

the speaker system according to claim 1 ; and

a housing accommodating the speaker system thereinside.

7. A vehicle comprising:

the speaker system according to claim 1 ; and

a vehicle body accommodating the speaker system thereinside.