Earphone cushions

1. A cushion comprising a first material and a second material in a unitary structure, and formed into a first region and a second region, in which:

the first region defines an exterior surface shaped to fit the concha of a human ear,

the second region defines an exterior surface shaped to fit the ear canal of a human ear,

the first and second regions together define an interior surface shaped to couple the cushion to acoustic elements of an earphone,

the first material occupies a first volume adjacent to the interior surface,

the second material occupies a second volume between the first volume and the first and second exterior surfaces, and

the first and second materials are of different hardnesses.

2. The cushion of claim 1 in which the second material has a hardness in the range of about 3 shore A to about 12 shore A.

3. The cushion of claim 2 in which the second material has a hardness of about 8 shore A.

4. The cushion of claim 1 in which the first material has a hardness in the range of about 30 shore A to about 90 shore A.

5. The cushion of claim 4 in which the first material has a hardness of about 40 shore A.

6. The cushion of claim 1 in which the first volume extends into the first region, such that the first region has a stiffness greater than the stiffness of the second material.

7. The cushion of claim 1 in which the first volume comprises a ring-shaped portion to retain the cushion to the earphone.