Earphones
A headphone includes an acoustic transducer having a sound-radiating surface that moves along a first axis, a housing enclosing the acoustic transducer, a first acoustic chamber defined by a first side of the acoustic transducer and a first portion of the housing, the first acoustic chamber including a first reactive port in a serial configuration with an acoustic resistance to couple the first acoustic chamber with space outside the headphone, a second acoustic chamber defined by a second side of the acoustic transducer and a second portion of the housing, the second acoustic chamber separated from the first acoustic chamber by the acoustic transducer, and an opening coupling the second acoustic chamber to the wearer's ear canal along a second axis that is not parallel to the first axis.
1. An in-ear headphone comprising:
an acoustic transducer having a sound-radiating surface that moves along a first axis;
a housing enclosing the acoustic transducer;
a first acoustic chamber defined by a first side of the acoustic transducer and a first portion of the housing, the first acoustic chamber including a first reactive port in a serial configuration with an acoustic resistance to couple the first acoustic chamber with space outside the headphone;
a second acoustic chamber defined by a second side of the acoustic transducer and a second portion of the housing, the second acoustic chamber separated from the first acoustic chamber by the acoustic transducer;
an opening in a nozzle extending from the housing coupling the second acoustic chamber to a wearer's ear canal along a second axis through the nozzle that is not parallel to the first axis; and
a cushion removably attached to the housing, wherein the cushion at least partially couples the headphone to the wearer's ear, extends over the nozzle of the housing, and includes a mounting surface for supporting the housing from the wearer's ear.
2. The headphone of claim 1 wherein the second axis is substantially perpendicular to the first axis.
3. The headphone of claim 2 wherein the second axis is not coplanar with a plane perpendicular to the first axis and characterizing the sound-radiating surface.
4. The headphone of claim 1 wherein the first reactive port comprises an elongated tube, a first opening of the tube being open to the first acoustic chamber, and a second opening of the tube acoustically coupled to space outside the headphone through the acoustic resistance.
5. The headphone of claim 1 further comprising an acoustic damper in series with the nozzle.
6. The headphone of claim 1 wherein the first reactive port and the acoustic resistance reduce pressure variation on a face of the sound-radiating surface of the acoustic transducer exposed to the first acoustic chamber as compared to an otherwise-identical headphone lacking the first reactive port and acoustic resistance.
7. An in-ear headphone comprising:
an acoustic transducer having a sound-radiating surface that moves along a first axis;
a housing enclosing the acoustic transducer;
a first acoustic chamber defined by a first side of the acoustic transducer and a first portion of the housing, the first acoustic chamber including a first reactive port in a serial configuration with an acoustic resistance to couple the first acoustic chamber with space outside the headphone;
a second acoustic chamber defined by a second side of the acoustic transducer and a second portion of the housing, the second acoustic chamber separated from the first acoustic chamber by the acoustic transducer;
an opening in a nozzle extending from the housing coupling the second acoustic chamber to a wearer's ear canal; and
a cushion removably attached to the housing, wherein the cushion at least partially couples the headphone to the wearer's ear, extends over the nozzle of the housing, and includes a mounting surface for supporting the housing from the wearer's ear
wherein
the first reactive port produces an acoustical reactive effect in the frequency response of the headphone that is greater than any acoustical resistive effect produced by the first reactive port, independently of the acoustic resistance, in the frequency response over a frequency range below about 100 Hz as measured in the ear canal.
8. The headphone of claim 7 wherein the nozzle extends from the second acoustic chamber and provides the opening coupling the second acoustic chamber to the ear canal.
9. The headphone of claim 8 wherein the nozzle extends the second acoustic chamber along a second axis that is not parallel to the first axis.
10. The headphone of claim 7 wherein the first reactive port comprises an elongated tube, a first opening of the tube being open to the first acoustic chamber, and a second opening of the tube acoustically coupled to space outside the headphone through the acoustic resistance.
11. The headphone of claim 7 further comprising an acoustic damper in series with the opening coupling the second acoustic chamber to the ear canal.
12. An in-ear headphone comprising:
an acoustic transducer having a sound-radiating surface that moves along a first axis;
a housing enclosing the acoustic transducer;
a first acoustic chamber defined by a first side of the acoustic transducer and a first portion of the housing, the first acoustic chamber including a first reactive port in a serial configuration with an acoustic resistance to couple the first acoustic chamber with space outside the headphone;
a second acoustic chamber defined by a second side of the acoustic transducer and a second portion of the housing, the second acoustic chamber separated from the first acoustic chamber by the acoustic transducer;
a nozzle having an opening coupling the second acoustic chamber to a wearer's ear canal and extending the second acoustic chamber at least partially into the ear canal along a second axis that is not parallel to the first axis; and
a cushion removably attached to the housing, wherein the cushion at least partially couples the headphone to the wearer's ear, extends over the nozzle, and includes a mounting surface for supporting the housing from the wearer's ear.
13. The headphone of claim 12 wherein the second axis is substantially perpendicular to the first axis.
14. The headphone of claim 13 wherein the second axis is not coplanar with a plane perpendicular to the first axis and characterizing the sound-radiating surface.
15. The headphone of claim 12 wherein the first reactive port comprises an elongated tube, a first opening of the tube being open to the first acoustic chamber, and a second opening of the tube acoustically coupled to space outside the headphone through the acoustic resistance.
16. The headphone of claim 12 wherein the first reactive port and the acoustic resistance reduce pressure variation on a face of the sound-radiating surface of the acoustic transducer exposed to the first acoustic chamber as compared to an otherwise-identical headphone lacking the first reactive port and acoustic resistance.
17. The headphone of claim 12 wherein:
the first reactive port produces an acoustical reactive effect in the frequency response of the headphone that is greater than any acoustical resistive effect produced by the acoustical resistance in the frequency response over a frequency range below about 100 Hz as measured in the ear canal.
18. The headphone of claim 12 further comprising an acoustic damper in series with the nozzle.